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O 


THE 


DESCENT  OF  MAN, 


AND 


ACTION  IN  RELATION  TO  SEX, 


By  CHARLES  DARWIN,  M.  A.,  R  R.  S. 


REPRINTED    FROM    THE    SECOND    ENGLISH     EDITION, 
REVISED  AND  AUGMENTED. 


ILLUSTRATED. 


NEW  YORK: 

CLARKE,  GIVEN  AND  HOOPER, 

PUBLISHERS. 


'^     FRANK  C.  BAKER, 
^^1^        ^.        Chicago,  Ills 


PREFACE    TO    THE    SECOND   EDITION. 


During  the  successive  reprints  of  the  first  edition  of 
this  work,  published  in  1871,  I  was  able  to  introduce  sev- 
eral important  corrections;  and  now  that  more  time  has 
elapsed  I  have  endeavored  to  profit  by  the  fiery  ordeal 
through  which  the  book  has  passed,  and  have  taken  ad- 
vantage of  all  the  criticisms  which  seem  to  me  sound.  I 
am  also  greatly  indebted  to  a  large  number  of  correspond- 
ents for  the  communication  of  a  surprising  number  of  new 
facts  and  remarks.  These  have  been  so  numerous  that  I 
have  been  able  to  use  only  the  more  important  ones;  and 
of  these,  as  well  as  of  the  more  important  corrections,  I 
will  append  a  list.  Some  new  illustrations  have  been  in- 
troduced and  four  of  the  old  drawings  have  been  replaced 
by  better  ones,  done  from  life  by  Mr.  T.  W.  Wood.  I 
must  especially  call  attention  to  some  observations  which  I 
owe  to  the  kindness  of  Prof.  Huxley  (given  as  a  supple- 
ment at  the  end  of  Part  I),  on  the  nature  of  the  differences 
between  the  brains  of  man  and  the  higher  apes.  I  have 
been  particularly  glad  to  give  these  observations,  because 
during  the  last  few  years  several  memoirs  on  the  subject 
have  appeared  on  the  Continent  and  their  importance  has 
been,  in  some  cases,  greatly  exaggerated  by  popular  writers. 

I  may  take  this  opportunity  of  remarking  that  my  critics 
frequently  assume  that  I  attribute  all  changes  of  corporeal 
structure  and  mental  power  exclusively  to  the  natural  se- 
lection of  such  variations  as  are  often  called  spontaneous; 
whereas,  even  in  the  first  edition  of  the  "  Origin  of 
Species,^'  I  distinctly  stated  that  great  weight  must  be  at- 


iv  PREFACE, 

tributed  to  the  inherited  effects  of  use  and  disuse,  with  re- 
spect botli  to  the  body  and  mind.  I  also  attributed  some 
amount  of  modification  to  the  direct  and  prolonged  action 
of  changed  conditions  of  life.  Some  allowance,  too,  must 
be  made  for  occasional  reversions  of  structure;  nor  must  we 
forget  what  I  have  called  '^correlated''  growth,  meaning 
thereby  that  various  parts  of  the  organization  are  in  some 
unknown  manner  so  connected,  that  when  one  part  varies 
so  do  others;  and  if  variations  in  the  one  are  accumulated 
by  selection  other  parts  will  be  modified.  Again,  it  has 
been  said  by  several  critics  that  when  I  found  that  many 
details  of  structure  in  man  could  not  be  explained  through 
natural  selection,  I  invented  sexual  selection;  I  gave,  how- 
ever, a  tolerably  clear  sketch  of  this  principle  in  the  first 
edition  of  the  '^  Origin  of  Species,"  and  I  there  stated  that 
it  was  applicable  to  man.  This  subject  of  sexual  selection 
has  been  treated  at  full  length  in  the  present  work,  simply 
because  an  opportunity  was  here  first  afforded  me.  I  have 
been  struck  with  the  likeness  of  many  of  the  half -favorable 
criticisms  on  sexual  selection,  with  those  which  appeared 
at  first  on  natural  selection;  such  as,  that  it  would  explain 
some  few  details,  but  certainly  was  not  applicable  to  the 
extent  to  which  I  have  employed  it.  My  conviction  of  the 
power  of  sexual  selection  remains  unshaken  ;  but  it  is 
probable,  or  almost  certain,  that  several  of  my  conclusions 
will  hereafter  be  found  erroneous;  this  can  hardly  fail  to 
be  the  case  in  the  first  treatment  of  a  subject.  When 
naturalists  have  become  familiar  with  the  idea  of  sexual 
selection,  it  will,  as  I  believe,  be  much  more  largely  ac- 
cepted; and  it  has  already  been  fully  and  favorably  re- 
ceived by  several  capable  judges. 

Down,  Beckenham,  Kent,  September,  1874 


CONTENTS. 


Page. 
IlTTRODUCnON 1 

PART  I. 

THE  DESCENT  OR  ORIGIN  OF  MAN. 


CHAPTER  I. 
The  Evidence  of  the  Descent  of  Man  from  Some  Lower  Fonn 


..  ® 


CHAPTER  II. 
On  the  Manner  of  Development  of  Man  from  Some  Lower  Form      29 

CHAPTER  III. 

Comparison  of  the  Mental  Powers  of   Man  and  the  Lower 

Animals 73 

CHAPTER  IV. 

Comparison  of  the  Mental  Powers  of  Man  and  the   Lower 

Animals — continued 110 

CHAPTER  V. 

On  the  Development  of  the  Intellectual  and  Moral  Faculties 
■  During  Primeval  and  Civilized  Times 144 

CHAPTER  VI. 
On  the  Affinities  and  Genealogy  of  Man 166 

CHAPTER  VII. 
On  the  Races  of  Man 189 


Vi  CONTENTS. 

PART   II. 

SEXUAL    SELECTION" 


CHAPTER  VIII. 

Paob. 
principles  of  Sexual  Selection 234 

CHAPTER  IX. 

Secondary  Sexual  Characters  in  the  Lower  Classes  of  the  Ani- 
mal Kingdom 294 

CHAPTER  X. 
Secondary  Sexual  Characters  of  Insects 311 

CHAPTER  XL 
Insects,  continued — Order  Lepidoptera.    Butterflies  and  Moths.    348 

CHAPTER  XII. 

Secondary    Sexual    Characters    of    Fishes,  Amphibians,   and 

Reptiles 375 

CHAPTER  XIII. 
Secondary  Sexual  Characters  of  Birds 407 

CHAPTER  XIV. 
BSx^ia— continued 459 

CHAPTER   XV. 
'BUx^?,— continued 505 

CHAPTER  XVI. 
Birds — concluded , . . .    528 

CHAPTER  XVII. 
^condar^  Sexual  Characters  of  Mammals , . . . , ,    57Q 


CONTENTS,  vii 

CHAPTER  XVIII. 

Page. 

Secondary  Sexual  Characters  of  Mammals — cantinued 600 

PART    III. 

SEXUAL  SELECTION'  IN  RELATION  TO  MAN,  AND  CONCLUSION. 

CHAPTER  XIX. 
Secondary  Sexual  Characters  of  Man 634 

CHAPTER  XX. 
Secondary  Sexual  Characters  of  M&n—contimted 668 

CHAPTER  XXI. 
General  Summary  and  Conclusion 693 

Supplemental  Note.  . .  709 

Index 715 


THE  DESCENT  OF  MAN; 


AND 


SELECTION  IN  RELATION  TO  SEX. 


INTRODUCTION. 

The  nature  of  the  following  work  will  be  best  understood 
by  a  brief  account  of  how  it  came  to  be  written.  During 
many  years  I  collected  notes  on  the  origin  or  descent  of 
man,  without  any  intention  of  publishing  on  the  subject, 
but  rather  with  the  determination  not  to  publish,  as  I 
thought  that  I  should  thus  only  add  to  the  prejudices 
against  my  views.  It  seemed  to  me  sufficient  to  indicate, 
in  the  first  edition  of  my  ^'  Origin  of  Species,^'  that  by  this 
work  "  light  would  be  thrown  on  the  origin  of  man  and  his 
history;"  and  this  implies  that  man  must  be  included  with 
other  organic  beings  in  any  general  conclusion  respecting 
his  manner  of  appearance  on  this  earth.  Now  the  case 
wears  a  wholly  different  aspect.  When  a  naturalist  like 
Carl  Vogt  ventures  to  say  in  his  address  as  President  of  the 
National  Institution  of  Geneva  (1869),  "  personne,  en 
Europe  au  moins,  n'ose  plus  soutenir  la  creation  independ- 
ante  et  de  toutes  pieces,  des  especes,"  it  is  manifest  that  at 
least  a  large  number  of  naturalists  must  admit  that  species 
are  the  modified  descendants  of  other  species;  and  this  es- 
pecially holds  good  with  the  younger  and  rising  naturalists. 
The  greater  number  accept  the  agency  of  natural  selection; 
though  some  urge,  whether  with  justice  the  future  must 
decide,  that  I  have  greatly  overrated  its  importance.  Of 
the  older  and  honored  chiefs  in  natural  science,  many  un- 
fortunately are  still  opposed  te  evolution  in  every  form. 

In  consequence  of  the  views  now  adopted  by  most  natu- 
ralists, and  which  will  ultimately,  as  in  every  other  ciise,  be 


2  THE  DESCENT  OF  MAN, 

followed  by  others  who  are  not  scientific,  I  have  been  led  to 
put  together  my  notes,  so  as  to  see  how  far  the  general  con- 
clusions arrived  at  in  my  former  works  were  applicable  to 
man.  This  seemed  all  the  more  desirable,  as  I  had  never 
deliberately  applied  these  views  to  a  species  taken  singly. 
AVhen  we  confine  our  attention  to  any  one  form,  we  are  de- 
prived of  the  weighty  arguments  derived  from  the  nature 
of  the  afiinities  which  connect  together  whole  groups  of 
organisms — their  geographical  distribution  in  past  and  pres- 
ent times,  and  their  geological  succession.  The  homologi- 
cal  structure,  embryological  development,  and  rudimentary 
organs  of  a  species  remain  to  be  considered,  whether  it  be 
man  or  any  other  animal,  to  which  our  attention  may  be 
directed;  but  these  great  classes  of  facts  afford,  as  it  ap- 
pears to  me,  ample  and  conclusive  evidence  in  favor  of  the 
principle  of  gradual  evolution.  The  strong  support  derived 
from  the  other  arguments  should,  however,  always  be  kept 
before  the  mind. 

The  sole  object  of  this  work  is  to  consider,  firstly, 
whether  man,  like  every  other  species,  is  descended  from 
some  pre-existing  form;  secondly,  the  manner  of  his  devel- 
opment; and  thirdly,  the  value  of  the  differences  between 
the  so-called  races  of  man.  As  I  shall  confine  myself  to 
these  points,  it  will  not  be  necessary  to  describe  in  detail 
the  differences  between  the  several  races — an  enormous  sub- 
ject which  has  been  fully  discussed  in  many  valuable  works. 
The  high  antiquity  of  man  has  recently  been  demonstrated 
by  the  labors  of  a  host  of  eminent  men,  beginning  with  M. 
Boucher  de  Perthes;  and  this  is  the  indispensable  basis  for 
understanding  his  origin.  I  shall,  therefore,  take  this 
conclusion  for  granted,  and  may  refer  my  readers  to  the 
admirable  treatises  of  Sir  Charles  Lyell,  Sir  John  Lubbock, 
and  others.  Nor  shall  I  have  occasion  to  do  more  than  to 
allude  to  the  amount  of  difference  between  man  and  the 
anthropomorphous  apes;  for  Prof.  Huxley,  in  the  opinion 
of  most  competent  judges,  has  conclusively  shown  that  in 
every  visible  character  man  differs  less  from  the  higher 
apes  than  these  do  from  the  lower  members  of  the  same 
order  of  Primates. 

This  work  contains  hardly  any  original  facts  in  regard 
to  man;  but  as  the  conclusions  at  which  I  arrived,  after 
drawing  up  a  rough  draft,  appeared  to  me  interesting,  I 
thought  that  they  might  interest  others.     It  has  often  and 


INTRODUCTION.  3 

confidently  been  asserted  that  man's  origin  can  never  be 
known:  but  ignorance  more  frequently  begets  confidence 
than  does  knowledge:  it  is  those  who  know  little,  and  not 
those  who  know  much,  who  so  positively  assert  that  this  or 
that  problem  will  never  be  solved  by  science.  The  con- 
clusion that  man  is  the  co-descendant  with  other  species  of 
some  ancient,  lower,  and  extinct  form,  is  not  in  any  degree 
new.  Lamarck  long  ago  came  to  this  conclusion,  which 
has  lately  been  maintained  by  several  eminent  naturalists 
and  philosophers;  for  instance,  by  Wallace,  Huxley,  Lyell, 
Vogt,  Lubbock,  Biichner,  Rolle,  etc.,*  and  especially  by 
Hackel.  This  last  naturalist,  besides  his  great  work, 
'^Generelle  Morphologic''  (1866),  has  recently  (1868, 
with  a  second  edition  in  1870),  published  his  ''  Naturliche 
Schopfungsgeschichte,"  in  which  he  fully  discusses  the 
genealogy  of  man.  If  this  work  had  appeared  before  my 
essay  had  been  written,  I  should  probably  never  have  com- 
pleted it.  Almost  all  the  conclusions  at  which  I  have 
arrived  I  find  confirmed  by  this  naturalist,  whose  knowl- 
edge on  many  points  is  much  fuller  than  mine.  Wherever 
I  have  added  any  fact  or  view  from  Prof.  Hackel's  writ- 
ings, I  give  his  authority  in  the  text;  other  statements  I 
leave  as  they  originally  stood  in  my  manuscript,  occasion- 
ally giving  in  the  footnotes  references  to  his  works,  as  a 
confirmation  of  the  more  doubtful  or  interesting  points. 

During  many  years  it  has  seemed  to  me  highly  probable 
that  sexual  selection  has  played  an  important  part  in 
differentiating  the  races  of  man;  but  in  my  '*  Origin 
of  Species"  (first  edition)  I  contented  myself  by 
merely  alluding  to  this  belief.  When  I  came  to  apply  this 
view  to  man,  I  found  it  indispensable  to  treat  the  whole 

*  As  the  works  of  the  first-named  authors  are  so  well  known,  I 
need  not  give  the  titles ;  but  as  those  of  the  latter  are  less  well 
known  in  England,  I  will  give  them  :  "  Sechs  Vorlesungen  iiber  die 
Darwin'sche  Theorie,"  zweite  Auflage,  1868,  von  Dr.  L.  Biichner  ; 
translated  into  French  under  the  title  "Conferences  sur  la  Theorie 
Darwinienne,"  1869.  "  Der  Mensch,  im  Lichte  der  Darwin'sche 
Lehre,"  1865,  von  Dr.  F.  Rolle.  I  will  not  attempt  to  give  references 
to  all  the  authors  who  have  taken  the  same  side  of  the  question. 
Thus  G.  Canestrini  has  published  ("  Annuario  della  Soc.  d.  Nat.," 
Modena,  1867,  p.  81),  a  very  curious  paper  on  rudimentary  characters, 
as  bearing  on  the  origin  of  man.  Another  work  has  (1869)  been 
published  by  Dr.  Francesco  Barrago,  bearing  in  Italian  the  title 
of  ' '  Man,  made  in  the  image  of  God,  was  also  made  in  the  image  of 
the  ape." 


4  THE  DESCENT  OF  MAN. 

subject  in  full  detail.*  Consequently,  the  second  part  of 
the  present  work,  treating  of  sexual  selection,  has  extended 
to  an  inordinate  length,  compared  with  the  first  part;  but 
this  could  not  be  avoided. 

I  had  intended  adding  to  the  present  volume  an  essay  on 
the  expression  of  the  various  emotions  by  man  and  the 
lower  animals.  My  attention  was  called  to  this  subject 
many  years  ago  by  Sir  Charles  BelFs  admirable  work. 
This  illustrious  anatomist  maintains  that  man  is  endowed 
with  certain  muscles  solely  for  the  sake  of  expressing  his 
emotions.  As  this  view  is  obviously  opposed  to  the  belief 
that  man  is  descended  from  some  other  and  lower  form,  it 
was  necessary  for  me  to  consider  it.  I  likewise  wished  to 
ascertain  how  far  the  emotions  are  expressed  in  the  same 
manner  by  the  different  races  of  man.  But  owing  to  the 
length  of  the  present  work,  I  have  thought  it  better  to  re- 
serve my  essay  for  separate  publication. 

*  Prof.  Hackel  was  the  only  author,  who,  at  the  time  when  this 
work  first  appeared,  had  discussed  the  subject  of  sexual  selection, 
and  had  seen  its  full  importance,  since  the  publication  of  the 
"Origin;"  and  this  he  did  in  a  very  able  manner  in  his  various 
works. 


PART  I. 
THE  DESCENT  OR  ORIGIN  OF  MAN. 


CHAPTER  I. 


THE    EVIDENCE    OF    THE     DESCENT    OF    MAN    FKOM     SOME 
LOWER     FORM. 

Naturil^f  the  evidence  bearing  on  tlie  origin  of  man — Homologous 
sxruotares  in  man  and  the  lower  animals — Miscellaneous  points 
of  correspondence  —  Development  —  Rudimentary  structures, 
muscles,  sense-organs,  hair,  bones,  reproductive  organs,  etc. — 
The  bearing  of  these  three  great  classes  of  facts  on  the  origin  of 
man. 

He  who  wishes  to  decide  whether  man  is  the  modified 
descendant  of  some  pre-existing  form,  would  probably  first 
inquire  whether  man  varies,  however  slightly,  in  bodily 
structure  and  in  mental  faculties;  and  if  so,  whether  the 
variations  are  transmitted  to  his  offspring  in  accordance 
with  the  laws  which  prevail  with  the  lower  animals.  Again, 
are  the  variations  the  result,  as  far  as  our  ignorance  permits 
us  to  judge,  of  the  same  general  causes,  and  are  they 
governed  by  the  same  general  laws,  as  in  the  case  of  other 
organisms;  for  instance,  by  correlation,  the  inherited  effects 
of  use  and  disuse,  etc.  ?  Is  man  subject  to  similar  malcon- 
f ormations,  the  result  of  arrested  development,  of  reduplica- 
tion of  parts,  etc.,  and  does  he  display  in  any  of  his  anoma- 
lies reversion  to  some  former  and  ancient  type  of  structure? 
It  might  also  naturally  be  inquired  wliether  man,  like  so 
many  other  animals,  has  given  rise  to  varieties  and  sub- 
races,  differing  but  slightly  from  each  other,  or  to  races 
differing  so  much  that  they  must  be  classed  as  doubtful 
species?  How  are  such  races  distributed  over  the  world; 
and  how,  when  crossed,  do  they  react  on  each  other  in  the 
first  and  succeeding  generations?  And  so  with  many  other 
points. 


g  i'UE  DESCENT  OF  MAN. 

The  inquirer  would  next  come  to  the  important  point, 
whether  man  tends  to  increase  at  so  rapid  a  rate,  as  to  lead 
to  occasional  severe  struggles  for  existence ;  and  conse- 
quently to  beneficial  variations,  whether  in  body  or  mind, 
being  preserved,  and  injurious  ones  eliminated.  Do  the 
races  or  species  of  men,  whichever  term  may  be  applied, 
encroach  on  and  replace  one  another,  so  that  some  finally 
become  extinct  ?  We  shall  see  that  all  these  questions,  as 
indeed  is  obvious  in  respect  to  most  of  them,  must  be  an- 
swered in  the  affirmative,  in  the  same  manner  as  with  the 
lower  animals.  But  the  several  considerations  Just  referred 
to  may  be  conveniently  deferred  for  a  time  :  and  we  will 
first  see  how  far  the  bodily  structure  of  man  shows  traces, 
more  or  less  plain,  of  his  descent  from  some  lower  form. 
In  succeeding  chapters  the  mental  powers  of  man,  in  com- 
parison with  those  of  the  lower  animals,  will  be  considered. 

TJie  Bodily  Structure  of  Man. — It  is  notorious  that  man 
is  constructed  on  the  same  general  type  or  model  as  other 
mammals.  All  the  bones  in  his  skeleton  can  be  compared 
with  corresponding  bones  in  a  monkey,  bat,  or  seal.  So  it 
is  with  his  muscles,  nerves,  blood-vessels,  and  internal  vis- 
cera. The  brain,  the  most  important  of  all  the  organs, 
follows  the  same  law,  as  shown  by  Huxley  and  other  anato- 
mists. Bischoff,*  who  is  a  hostile  witness,  admits  that  every 
chief  fissure  and  fold  in  the  brain  of  man  has  its  analogy 
in  that  of  the  orang  ;  but  he  adds  that  at  no  period  of  de- 
velopment do  their  brains  perfectly  agree  ;  nor  could  per- 
fect agreement  be  expected,  for  otherwise  their  mental  pow- 
ers would  have  been  the  same.  Vulpianf  remarks  :  "  Les 
difierences  reelles  qui  existent  entre  I'encephale  de  Thomme 
et  celui  des  singes  superieurs,  sont  bein  minimes.  II  ne 
faut  pas  se  faire  d'illusions  a  cet  egard.  L'homme  est  bein 
plus  pres  des  singes  anthropomorphes  par  les  caract^res 
anatomiques  de  son  cerveau  que  ceux-ci  ne  le  sont  non  seul- 
ement  des  autres  mammiferes,  mais  meme  de  certains  quad- 
rumanes,  des  guenons  et  des  macaques."     But  it  would  be 

* "  Grosshirnwindungen  des  Menschen,"  1868,  s.  96.  The  con- 
clusions of  this  author,  as  well  as  those  of  Gratiolet  and  Aeby,  con- 
cerning the  brain,  will  be  discussed  by  Prof.  Huxley  in  the  Appendix 
alluded  to  in  the  Preface  to  this  edition. 

f  "Lee.  sur  la  Phys.,"  1866,  p.  890,  as  quoted  by  M.  Dally, 
*'  L'Ordre  des  Primates  et  le  Trans formisme,"  1868,  p.  29. 


HOMOLOmCAL  STRUCTURES.  ^ 

'superfluous  here  to  give  further  details  on  the  correspond- 
ence between  man  and  the  higher  mammals  in  the  structure 
of  the  brain  and  all  other  parts  of  the  body. 

It  may,  however,  be  worth  while  to  specify  a  few  points, 
not  directly  or  obviously  connected  with  structure,  by  which 
this  correspondence  or  relationship  is  well  shown. 

Man  is  liable  to  receive  from  the  lower  animals,  and 
to  communicate  to  them,  certain  diseases,  as  hydrophobia, 
variola,  the  glanders,  syphilis,  cholera,  herpes,  etc.;*  and 
,this  fact  proves  the  close  similarity f  of  their  tissues  and 
blood,  both  in  minute  structure  and  composition,  far  more 
plainly  than  does  their  comparison  under  the  best  micro- 
scope, or  by  the  aid  of  the  best  chemical  analysis.  Mon- 
keys are  liable  to  many  of  the  same  non-contagious  diseases 
as  we  are;  thus  Rengger,|  who  carefully  observed  for  a  long 
time  the  Cehus  AzarcB  in  its  native  land,  found  it  liable  to 
catarrh,  with  the  usual  symptoms,  and  which,  when  often 
recurrent,  led  to  consumption.  These  monkeys  suffered 
also  from  apoplexy,  inflammation  of  the  bowels,  and  cata- 
ract in  the  eye.  The  younger  ones  when  shedding  their 
milk-teeth  often  died  from  fever.  Medicines  produced  the 
same  effect  on  them  as  on  us.  Many  kinds  of  monkeys 
have  a  strong  taste  for  tea,  coffee,  and  spirituous  liquors: 
they  will  also,  as  I  have  myself  seen,  smoke  tobacco  with 
pleasure.  §  Brehm  asserts  that  the  natives  of  north-eastern 
Africa  catch  the  wild  baboons  by  exposing  vessels  with 
strong  beer,  by  which  they  are  made  drunk.  He  has  seen 
some  of  these  animals,  which  he  kept  in  confinement,  in 

*  Dr.  W.  Lauder  Lindsay  lias  treated  this  subject  at  some  length 
in  the  "  Journal  of  Mental  Science,"  July,  1871;  and  in  the  "Edin- 
burgh Veterinary  Review,"  July,  1858. 

f  A  Reviewer  has  criticised  ("British  Quarterly  Review,"  Oct.  1, 
1871,  p.  472)  what  I  have  here  said  with  much  severity  and  contempt; 
but  as  I  do  not  use  the  term  identity,  I  cannot  see  that  I  am  greatly 
in  error.  There  appears  to  me  a  strong  analogy  between  the  same 
infection  or  contagion  producing  the  same  result,  or  one  closely  simi- 
lar, in  two  distinct  animals,  and  the  testing  of  two  distinct  fluids  by 
the  same  chemical  reagent. 

J  "  Naturgeschichte  der  Siiugethiere  von  Paraguay,"  1830,  s.   50. 

§  The  same  tastes  are  common  to  some  animals  much  lower  in  the 
scale.  Mr.  A.  Nichols  informs  me  that  he  kept  in  Queensland,  in 
Australia,  three  individuals  of  the  Phaseolarctus  cinerens;  and  that, 
without  having,  been  taught  in  any  way,  they  acquired  a  strong  tast-e 
for  rum  and  smoking  tobacco. 


g  THE  DESCENT  OF  MAN. 

this  state;  and  lie  gives  a  laughable  account  of  their  behav- 
ior and  strange  grimaces.  On  the  following  morning  they 
were  very  cross  and  dismal;  they  held  their  aching  heads 
with  both  hands,  and  wore  a  most  pitiable  expression;  when 
beer  or  wine  was  offered  them,  they  turned  away  with  dis- 
gust, but  relished  the  juice  of  lemons.*  An  American 
monkey,  an  Ateles,  after  getting  drunk  on  brandy,  would 
never  touch  it  again,  and  thus  was  wiser  than  many  men. 
These  trifling  facts  prove  how  similar  the  nerves  of  taste 
must  be  in  monkeys  and  man,  and  how  similarly  their  whole 
nervous  system  is  affected. 

Man  is  infested  with  internal  parasites,  sometimes  causing 
fatal  effects;  and  is  plagued  by  external  parasites,  all  of 
which  belong  to  the  same  genera  or  families  as  those  infest- 
ing other  mammals,  and  in  the  case  of  scabies  to  the  same 
species,  t  Man  is  subject,  like  other  mammals,  birds,  and 
even  insects,  J  to  that  mysterious  law,  which  causes  certain 
normal  processes,  such  as  gestation,  as  well  as  the  matura- 
tion and  duration  of  various  diseases,  to  follow  lunar  periods. 
His  wounds  are  repaired  by  the  same  process  of  healing; 
and  the  stumps  left  after  the  amputation  of  his  limbs,  es- 
pecially during  an  early  embryonic  period,  occasionally 
possess  some  power  of  regeneration,  as  in  the  lowest 
animals.  § 

The  whole  process  of  that  most  important  function,  the 
reproduction  of  the  species,  is  strikingly  the  same  in  all 
mammals,  from  the  first  act  of  courtship  by  the  male,  ||  to 

*Brelim,  "  Thierleben,"  B.  i,  1864,  s.  75,  86.  On  the  Ateles,  s. 
105.     For  other  analogous  statements,  see  s.  25,  107. 

f  Dr.  W.  Lauder  Lindsay,  "Edinburgh  Veterinary  Review,"  July, 
1858,  p.  13. 

\  With  respect  to  insects  see  Dr.  Laycock  "  On  a  General  Law  of 
Vital  Periodicity,"  "British  Association,"  1842.  Dr.  Macculloch, 
"  Silliman's  North  American  Journal  of  Science,"  vol.  xvii,  p.  305, 
has  seen  a  dog  suffering  from  tertian  ague.  Hereafter  I  shall  return 
to  this  subject. 

§1  have  given  the  evidence  on  this  head  in  ray  "Variation  of 
Animals  and  Plants  under  Domestication,"  vol.  ii,  p.  15,  and  more 
could  be  added. 

I  Mares  e  diversis  generibus  Quadrumanorum  sine  dubio  dignos- 
cunt  feminas  humauas  a  maribus.  Primum,  credo,  odoratu,  postea 
aspectu.  Mr.  Youatt,  qui  diu  in  Hortis  Zoologicis  (Bestiariis)  medi- 
cus  animalium  erat,  vir  in  rebus  observandis  cautus  et  sagax,  hoc 
mihi  certissime  probavit,  et  curatores  ejusdem  loci  et  alii  e  ministris 
confirmaverunt.     Sir  Andrew  Smith  et  Brehm  notabant  idem  in  Cyno- 


HOMOLOGJCAL  STRUCTURES.  0 

the  birth  and  nurturing  of  the  young.  Monkeys  are  bom 
in  almost  as  helpless  a  condition  as  our  own  infants;  and  in 
certain  genera  the  young  differ  fully  as  much  in  appearance 
from  the  adults,  as  do  our  children  from  their  full-grown 
parents.*  It  has  been  urged  by  some  writers,  as  an  import- 
ant distinction,  that  with  man  the  young  arrive  at  maturity 
at  a  much  later  age  than  with  any  other  animal:  but  if  we 
look  to  the  races  of  mankind  which  inhabit  tropical  coun- 
tries the  difference  is  not  great,  for  the  orang  is  believed 
not  to  be  adult  till  the  age  of  from  ten  to  fifteen  years,  f 
Man  differs  from  woman  in  size,  bodily  strength,  hairiness, 
etc.,  as  well  as  in  mind,  in  the  same  manner  as  do  the  two 
sexes  of  many  mammals.  So  that  the  correspondence  in 
general  structure,  in  the  minute  structure  of  the  tissues,  in 
chemical  composition  and  in  constitution,  between  man  and 
the  higher  animals,  especially  the  anthropomorphous  apes,  ^ 
is  extremly  close. 

Embryonic  Development. — Man  is  developed  from  an 
o^'ule,  about  the  125th  of  an  inch  in  diameter,  which  differs 
in  no  respect  from  the  ovules  of  other  animals.  The 
embryo  itself  at  a  very  early  period  can  hardly  be  distin- 
guished from  that  of  other  members  of  the  vertebrate  king- 
dom. At  this  period  the  arteries  run  in  arch-like  branches, 
as  if  to  carry  the  blood  to  branchiae  which  are  not  present 
in  the  higher  vertebrata,  though  the  slits  on  the  sides  of  the 
neck  still  remain  (/,  g,  fig.  1),  marking  their  former  posi- 
tion. At  a  somewhat  later  period,  when  the  extremities 
are  developed,  *^  the  feet  of  lizards  and  mammals,"  as  the 
illustrious  Von  Baer  remarks,  "  the  wings  and  feet  of  birds, 
no  less  than  the  hands  and  feet  of  man,  all  arise  from 
the  same  fundamental  form,"     It  is,  says  Prof.  Huxley,]; 

cepbalo.  Illustrissimus  Cuvier  etiam  narrat  multa  de  liac  re,  qua 
ut  opinor,  nihil  turpius  potest  indicari  inter  omnia  hominibus  et 
Quadrumanis  communia.  Narrat  enijn  Cynocephalum  quendam  in 
furorem  incidere  aspectu  feminarum  aliquarum,  sed  nequaquam  ac- 
cendi  tanto  furore  ab  omnibus.  Semper  eligebat  juniores,  et  dignos- 
cebat  in  turba,  et  advocabat  voce  gestuque. 

*Tbis  remark  is  made  with  respect  to  Cynocephalus  and  the 
anthropomorphous  apes  by  Geoffroy  Saint-Hilaire  and  F.  Cuvier, 
•*  Hist,  Nat.  des  Manimiferes,"  torn,  i,  1824. 

t  Huxley,  "  Man's  Place  in  Nature."  1863,  p.  34. 

X  Ibid.,  p.  67. 


10  THE  DESCENT  OF  MAN. 

"quite  in  the  later  stages  of  development  that  the  yonng 
human  l)eing  })resents  marked  differences  from  the  young 
ape,  while  the  latter  departs  as  much  from  the  dog  in  its 
developments,  as  the  man  does.  Startling  as  this  last  asser- 
tion may  appear  to  be,  it  is  demonstrably  true." 

As  some  of  my  readers  may  never  have  seen  a  drawing  of 
an  embryo,  I  have  given  one  of  man  and  another  of  a  dog, 
at  about  the  sjime  early  stage  of  development,  carefully 
copied  from  two  works  of  undoubted  accuracy,* 

After  the  foregoing  statements  made  by  such  high 
authorities,  it  would  be  superfluous  on  my  part  to  give  a 
number  of  borrowed  details,  showing  that  the  embryo  of 
man  closely  resembles  that  of  other  mammals.  It  may, 
however,  be  added,  that  the  human  embryo  likewise  resem- 
bles certain  low  forms  when  adult  in  various  points  of 
structure.  For  instance,  the  heart  at  first  exists  as  a  simple 
pulsating  vessel ;  the  excreta  are  voided  through  a  cloacal 
passage  ;  and  the  os  coccyx  projects  like  a  true  tail,  "  ex- 
tending considerably  beyond  the  rudimentary  legs.^f  I^ 
the  embryos  of  all  air-breathing  vertebrates,  certain  glands, 
called  the  corpora  Wolffiana,  correspond  with,  and  act 
like  the  kidneys  of  mature  fishes.  J;  Even  at  a  later 
embryonic  period,  some  striking  resemblances  between 
man  and  the  lower  animals  may  be  observed.  Bischoff 
says  that  "  the  convolutions  of  the  brain  in  a  human  foetus 
at  the  end  of  the  seventh  month  reach  about  the  same 
stage  of  development  as  in  a  baboon  when  adult.  "§ 
The  great  toe,  as  Prof.  Owen  remarks,!  "  which  forms 
the    fulcrum    when    standing    or    walking,    is    perhaps 

*The  human  abryo  (upper  fig.)  is  from  Ecker,  "  I  cones  Phys.," 
1851-1859,  tab.  xxx,  fig.  2.  This  embryo  was  ten  lines  in  length,  so 
that  the  drawing  is  much  magnified.  The  embryo  of  the  dog  is  from 
Bischoff,  "  'ntwicklungsgeschichte  des  Hunde-Eies,"  1845,  tab.  xi, 
fig.  42  B.  This  drawing  is  five  times  magnified,  the  embryo  being 
twenty-five  days  old.  The  internal  viscera  ave  been  omitted,  and 
the  uterine  appendages  in  both  drawings  removed.  I  was  directed 
to  these  figures  by  Prof.  Huxley,  from  whose  work,  "  Man's  Place  in 
Nature,"  the  idea  of  giving  them  was  taken.  Hackel  has  also  given 
analogous  drawings  in  his  **  Schfipfungsgeschichte." 

f  Prof.  Wyman  in  "  Proc.  of  American  Acad,  of  Sciences,"  vol.  iv, 
1860,  p.  17. 

JOwen,  "Anatomy  of  Vertebrates,"  vol.  i,  p.  533. 

§  "  Die  Grosshirnwindungen  des  Menschen,"  1868,  s.  95. 

\  "  Anatomy  of  Vertebrates,"  vol.  ii,  p.  553. 


mMOLOOiCAL  STRUCTURES, 


11 


Fig.  1. 


Upper  figure  human  embryo,  f»*om  Ecker. 
from  Bischoff. 


Lower  figure  that  of  a  dog. 


a.  Pore-brain,  cerebral  hemispheres, 
etc. 
6,  Mid-brain,  corpora  quadrigemina. 

c.  Hind  brain,  cerebellum,  medulla 
oblongata, 

d.  Eye. 

e.  Ear. 


/.  First  visceral  arch. 
g.  Second  visceral  arch. 
H.  Vertebral  columns  and  muscles 
in  process  of  development. 


i.  Anterior 


K.  Posterior  s 

L.  Tail  or  os  coccyx 


extremities. 


i  2  THE  DESCENT  OF  MAN. 

the  most  characteristic  peculiarity  in  the  human  struct- 
ure;" but  in  an  embryo,  about  an  inch  in  length,  Prof. 
Wyman*  found  "  that  the  great  toe  was  shorter  than  the 
others;  and,  instead  of  being  parallel  to  them,  projected  at 
an  angle  from  the  side  of  the  foot,  thus  corresponding  with 
the  permanent  condition  of  this  part  in  the  quadrumana." 
I  will  conclude  witli  a  quotation  from  Huxley,  f  who  after 
asking,  does  man  originate  in  a  different  way  from  a  dog, 
bird,  frog,  or  fish?  says,  "the  reply  is  not  doubtful  for  a 
moment;  without  question,  the  mode  of  origin,  and  the 
early  stages  of  the  development  of  man,  are  identical  with 
those  of  the  animals  immediately  below  him  in  the  scale: 
without  a  doubt  in  these  respects  he  is  far  nearer  to  apes 
than  the  apes  are  to  the  dog/^ 

Rudiments. — This  subject,  though  not  intrinsically  more 
important  than  the  two  last,  will  for  several  reasons  be 
treated  here  more  fully.  J  Not  one  of  the  higher  animals 
can  be  named  which  does  not  bear  some  part  in  a  rudi- 
mentary condition;  and  man  forms  no  exception  to  the 
rule.  Rudimentary  organs  must  be  distinguished  from 
those  that  are  nascent;  though  in  some  cases  the  distinction 
is  not  easy.  The  former  are  either  absolutely  useless,  such 
as  the  mammae  of  male  quadrupeds,  or  the  incisor  teeth  of 
ruminants,  which  never  cut  through  the  gums;  or  they  are 
of  such  slight  service  to  their  present  possessors,  that  we 
can  hardly  suppose  that  they  were  developed  under  the 
conditions  which  now  exist.  Organs  in  this  latter  state  are  not 
strictly  rudimentary,  but  they  are  tending  in  this  direction. 
Nascent  organs,  on  the  other  hand,  though  not  fully  devel- 
oped, are  of  high  service  to  their  possessors,  and  are  capa- 
ble of  further  development.  Rudinifiiitary  organs  are 
eminently  variable;  and  this  is  partly  intelligible,  as  they 
are  uselfiss,--X>r  nearly   useless,   and  _consequently  are  no 

*  "Proc.  Soc.  Nat.  Hist.,"  Boston   1863,  vol.  ix,  p.  185. 

f  "Man's  Place  in  Nature,"  p.  65. 

\  I  had  written  a  rough  copy  of  this  chapter  before  reading  a  valu- 
able paper,  **Caratteri  rudimentali  in  ordine  all'  origine  dell'  uomo" 
("  Annuario  della  Soc.  d.  Nat.,"  Modena,  1867,  p.  81),  by  G.  Canes- 
trini,  to  which  paper  1  am  considerably  indebted.  Hiickel  has  given 
admirable  discussions  on  this  whole  subject,  under  the  title  of  Dys- 
teleology,  in  his  "  Generelle  Morphologic"  and  "  SchOpf ungsge- 
schichte." 


RUDIMENTS.  13 

longer  subject  to  natural  selection.  They  often  become 
wholly  suppressed.  When  this  occurs,  they  are  neverthe- 
less liable  to  occasional  reappearance  through  reversion — a 
circumstance  well  worthy  of  attention. 

The  chief  agents  in  causing  organs  to  become  rudiment- 
ary seem  to  have  been  disuse  at  that  period  of  life  when 
the  organ  is  chiefly  used  (and  this  is  generally  during  matu- 
rity), and  also  inheritance  at  a  corresponding  period  of  life. 
The  term  * 'disuse"  does  not  relate  merely  to  the  lessened 
action  of  muscles,  but  includes  a  diminished  flow  of  blood 
to  a  part  or  organ,  from  being  subjected  to  fewer  altera- 
tions of  pressure,  or  from  becoming  in  any  way  less  habitu- 
ally active.  Rudiments,  however,  may  occur  in  one  sex 
of  those  parts  which  are  normally  present  in  the  other  sex; 
and  such  rudiments,  as  we  shall  hereafter  see,  have  often 
originated  in  a  way  distinct  from  those  here  referred  to. 
In  some  cases,  organs  have  been  reduced  by  means  of  nat- 
ural selection,  from  having  become  injurious  to  the  species 
under  changed  habits  of  life.  The  process  of  reduction  is 
probably  often  aided  through  the  two  principles  of  com- 
pensation and  economy  of  growth;  but  the  later  stages  of 
reduction,  after  disuse  has  done  all  that  can  fairly  be  at- 
tributed to  it,  and  when  the  saving  to  be  effected  by  the 
economy  of  growth  would  be  very  small,*  are  difficult  to 
understand.  The  final  and  complete  suppression  of  a  part, 
already  useless  and  much  reduced  in  size,  in  which  case 
neither  compensation  nor  economy  come  into  play,  is 
perhaps  intelligible  by  the  aid  of  the  hypothesis  of  pangene- 
sis. But  as  the  whole  subject  of  rudimentary  organs  has 
been  discussed  and  illustrated  in  my  former  works,  f  I  need 
here  say  no  more  on  this  head. 

Rudiments  of  various  muscles  have  been  observed  in 
many  parts  of  the  human  body  ;J:  and  not  a  few  muscles, 

*  Some  good  criticisms  on  this  subject  have  been  given  by  Messrs. 
Murie  and  Mivart.  in  "  Transact.  Zoolog.  Soc,"  1869,  vol.  vii,  p.  92. 

f  "  Variation  of  Animals  and  Plants  under  Domestication,"  vol.  ii, 
pp.  317  and  397.     See  also  "Origin  of  Species." 

\  For  instance  M.  Richard  ("  Annales  des  Sciences  Xat.,  3d  series, 
Zoolog.,  1852,  tom.  xviii,  p.  13)  describes  and  figures  rudiments  of 
what  he  calls  the  "muscle  pedieux  de  la  main,"  which  he  says  is 
sometimes  "  infiniment  petit."  Another  muscle,  called  "  le  tibial 
posterieur,"  is  generally  quite  absent  in  the  hand,  but  appears  from 
time  to  time  in  a  more  or  less  rudimentary  condition. 


14  THE  DESCENT  OF  MAN. 

which  are  regularly  present  in  some  of  the  lower  animals, 
can  occasionally  be  detected  in  man  in  a  greatly  reduced  con- 
dition. Every  one  must  have  noticed  the  power  which  many 
animals,  especially  horses,  possess  of  moving  or  twitching 
their  skin  ;  and  this  is  effected  by  the  pa}miciilus  carnosus. 
Remnants  of  this  muscle  in  an  efficient  state  are  found  in 
various  parts  of  our  bodies  ;  for  instance,  the  muscle  on  the 
forehead,  by  which  the  eyebrows  are  raised.  The  platysma 
my 0 ides,  which  is  well  developed  on  the  neck,  belongs  to 
^is  system.  Prof.  Turner,  of  Edinburgh,  has  occa- 
sionally detected,  as  he  informs  me,  muscular  fasciculi  in 
five  different  situations,  namely  in  the  axillae,  near  the 
scapulae,  etc.,  all  of  which  must  be  referred  to  the  system 
of  the  panniculus.  He  has  also  shown*  that  the  imisculus 
sternalis  or  sterualis  hrutorum,  which  is  not  an  extension 
of  the  rectus  abdominalis,  but  is  closely  allied  to  the,  j^an- 
7iicuhis,  occurred  in  the  ])roportion  of  about  three  per  cent, 
in  upwards  of  600  bodies ;  he  adds,  that  this  muscle  affords 
*^an  excellent  illustration  of  the  statement  '^^  that  occasional 
and  rudimentary  structures  are  especially  liable  to  variation 
in  arrangement." 

Some  few  persons  have  the  power  of  contracting  the 
superficial  muscles  on  their  scalps ;  and  these  muscles  are 
in  a  variable  and  partially  rudimentary  condition.  M.  A. 
de  Candolle  has  communicated  to  me  a  curious  instance  of 
the  long-continued  persistence  or  inheritance  of  this  power, 
as  well  as  of  its  unusual  development.  He  knows  a  family, 
in  which  one  member,  the  present  head  of  the  family, 
could,  when  a  youth,  pitch  several  heavy  books  from  his 
head  by  the  movement  of  the  scalp  alone ;  and  he  won 
wagers  by  performing  this  feat.  His  father,  uncle,  grand- 
father, and  his  three  children  possess  the  same  power  to  the 
same  unusual  degree.  This  family  became  divided  eight 
generations  ago  into  two  branches  ;  so  that  the  head  of  the 
above-mentioned  branch  is  cousin  in  the  seventh  degree  to 
the  hiead  of  the  other  branch.  This  distant  cousin  resides 
in  another  part  of  France  ;  and  on  being  asked  whether 
he  possessed  the  same  faculty,  immediately  exhibited  his 
power.  This  case  offers  a  good  illustration  how  persistent 
may  be  the  transmission  of  an  absolutely  useless  faculty, 
probably  derived  from  our  remote  semi-human  progenitors; 

*Prof.  W  Turner,  "  Proc.  Royal  Soc.  Edinburgh,"  1866-67,  p.  65. 


RUDIMENTS.  15 

since  many  monkeys  have,  and  frequently  use  the  power, 
of  largely  moving  their  scalps  up  and  down.* 

The  extrinsic  muscles  which  serve  to  move  the  external 
ear,  and  the  intrinsic  muscles  which  move  the  different 
parts,  are  in  a  rudimentary  condition  in  man,  and  they  all 
belong  to  the  system  of  the  pan nictilus  ;  they  are  also  vari- 
able in  development,  or  at  least  in  function.  I  have  seen 
one  man  who  could  draw  the  whole  ear  forward;  other  men 
can  draw  it  upward;  another  who  could  draw  it  backward;! 
and  from  what  one  of  these  persons  told  me,  it  is  probable 
that  most  of  us,  by  often  touching  our  ears,  and  thus 
directing  our  attention  toward  them,  could  recover  some 
power  of  movement  by  repeated  trials.  The  power  of  erect- 
ing and  directing  the  shell  of  the  ears  to  the  various  points 
of  the  compass,  is  no  doubt  of  the  highest  service  to  many 
animals,  as  they  thus  perceive  the  direction  of  danger;  but 
I  have  never  heard,  on  sufficient  evidence,  of  a  man  who 
possessed  this  power,  the  one  which  might  be  of  use  to  him. 
The  whole  external  shell  may  be  considered  a  rudiment,  to- 
gether with  the  various  folds  and  prominences  (helix  and 
anti-helix,  tragus,  and  anti-tragus,  etc.)  which  in  the  lower 
animals  strengthen  and  support  the  ear  when  erect,  with- 
out adding  much  to  its  weight.  Some  authors,  however, 
suppose  that  the  cartilage  of  the  shell  serves  to  transmit 
vibrations  to  the  acoustic  nerve;  but  Mr.  Toynbee,J;  after 
collecting  all  the  known  evidence  on  this  head,  concludes 
that  the  external  shell  is  of  no  distinct  use.  The  ears  of 
the  chimpanzee  and  orang  are  curiously  like  those  of  man, 
and  the  proper  muscles  are  likewise  but  very  slightly 
developed. §  I  am  also  assured  by  the  keepers  in  the 
Zoological  Gardens  that  these  animals  never  move  or  erect 

■ir  ears;  so  that  they  are  in  an  equally  rudimentary  condi- 
I    .vith  those  of  man,  as  far  as  function  is  concerned. 

*  See  my  "Expression  of  the  Emotions  in  Man  and  Animals,"  1872, 
p.  144. 

f  Canestrini  quotes  Hyrtl.  ("Annuario  della  So<i.  del  Naturalisti," 
Modena,  1867,  p.  97)  to  the  same  effect. 

i  "The  Diseases  of  the  Ear,"  by  J.  Toynbee,  F.  R.  S.,  1860,  p.  12. 
\  distinguished  physiologist.  Prof.  Preyer,  informs  me  that  he  liad 
lately  been  experimenting  on  the  function  of  the  shell  of  the  ear,  and 
has  come  to  nearly  the  same  conclusion  as  that  given  here. 

§Prof.  A.  Macalister,  "Annals  and  Mag.  of  Nat.  History,"  vol. 
vii,  1871,  p.  342. 


16  THE  DESCENT  OF  MAN, 

"Why  these  animals,  as  well  as  the  progenitors  of  man, 
should  have  lost  the  power  of  erecting  their  ears,  we  cannot 
say.  It  may  be,  though  I  am  not  satisfied  with  this  view, 
that  owing  to  their  arboreal  habits  and  great  strength  they 
were  but  little  exposed  to  danger,  and  so  during  a  length- 
ened period  moved  their  ears  but  little,  and  thus  gradually 
lost  the  power  of  moving  them.  This  would  be  a  parallel 
case  with  that  of  those  large  and  heavy  birds,  which,  from 
inhabiting  oceanic  islands,  have  not  been  exposed  to  the 
attacks  of  beasts  of  prey,  and  have  consequently  lost  the 
power  of  using  their  wings  for  flight.  The  inability  to 
move  the  ears  in  man  and  several  apes  is,  however,  partly 
compensated  by  the  freedom  with  which  they  can  move  the 
head  in  a  horizontal  plane,  so  as  to  catch  sounds  from  all 
directions.  It  has  been  asserted  that  the  ear  of  man  alone 
possesses  a  lobule;  but  "  2l  rudiment  of  it  is  found  in  the 
gorilla;"*  and,  as  I  hear  from  Prof.  Preyer,  it  is  not  rarely 
absent  in  the  negro. 

The  celebrated  sculptor,  Mr.  "VVoolner,  informs  me  of 
one  little  peculiarity  in  the  external  ear,  which  he  has  often 
observed  both  in  men  and  women,  and  of  which  he  per- 
ceived the  full  significance.  His  attention  was  first  called 
to  the  subject  while  at  work  on  his  figure  of  Puck,  to 
which  he  had  given  pointed  ears.  He  was  thus  led  to  ex- 
amine the  ears  of  various  monkeys,  and  subsequently  more 
carefully  those  of  men.  The  peculiarity  consists  in  a  little 
blunt  point,  projecting  from  the  inwardly  folded  margin, 
or  helix.  When  present,  it  is  developed  at  birth,  and,  ac- 
cording to  Prof.  Ludwig  Meyer,  more  frequently  in  man 
than  in  woman.  Mr.  Woolner  made  an  exact  model  of  one 
such  case,  and  sent  me  the  accompanying  drawing.  (Fig.  2. ) 
These  points  not  only  project  inward  toward  the  center  of 
the  ear,  but  often  a  little  outward  from  its  plane,  so  as  to  be 
visible  when  the  head  is  viewed  from  directly  in  front  or 
behind.  They  are  variable  in  size,  and  somewhat  in  position, 
standing  either  a  little  higher  or  lower  ;  and  they  sometimes 
occur  on  one  ear  and  not  on  the  other.  They  are  not  con- 
fined to  mankind,  for  I  observed  a  case  in  one  of  the  spider- 
monkeys  {A teles  Beelzebuth)  in  our  Zoological  Gardens; 
and  Mr.  E.  Ray  Lankester  informs  me  of  another  case  in  a 
chimpanzee  in  the  gardens  at  Hamburg.     The  helix  ob- 

*Mr.  St.  George  Mivart,  *'  Elementary  Anatomy,"  1873,  p.  396. 


RUDIMENTS. 


17 


viously  consists  of  the  extreme  margin  of  the  ear  folded 
inward  ;  and  this  folding  appears  to  be  in  some  manner 
connected  with  the  whole  external  ear  being  permanently 
pressed  backward.  In  many  monkeys,  wiiich  do  not  stand 
high  in  the  order,  as  baboons  and  some  species  of  Macacus,* 
the  upper  portion  of  the  ear  is  slightly  pointed,  and  the 
margin  is  not  at  all  folded  inward  ;  but  if  the  margin  were 
to  be  thus  folded,  a  slight  point  would  necessarily  project 
inward  toward  the  center,  and  probably  a  little  outward 
from  the  plane  of  the  ear ;  and  this  I  believe  to  be  their 
origin  in  many  cases.  On  the  other  hand,  Prof.  L.  Meyer, 
in  an  able  paper  recently  published,!  maintains  that  the 
whole  case  is  one  of  variability ; 
and  that  the  projections  are  not  real 
ones,  but  are  due  to  the  internal 
cartilage  on  each  side  of  the  points 
not  having  been  fully  developed.  I 
am  quite  ready  to  admit  that  this  is 
the  correct  explanation  in  many  in- 
stances, as  in  those  figured  by  Prof. 
Meyer,  in  which  there  are  several 
minute  points,  or  the  whole  margin 
is  sinuous.  I  have  myself  seen, 
through  the  kindness  of  Dr.  L.  Down, 
the  ear  of  a  microcephalous  idiot, 
on  which  there  is  a  projection  on  the 
outside  of  the  helix,  and  not  on  the 
inward  folded  edge,  so  that  this  point 
can  have  no  relation  to  a  former  apex 
of  the  ear.  Nevertheless  in  some 
cases,  my  original  view,  that  the  points  are  vestiges  of  the  tips 
of  formerly  erect  and  pointed  ears,  still  seems  to  me  probable. 
I  think  so  from  the  frequency  of  their  occurrence,  and  from  the 
general  correspondence  in  position  with  that  of  the  tip  of  a 
pointed  ear.  In  one  case,  of  which  a  photograph  has  been 
sent  me,  the  projection  is  so  large,  that  supposing,  in  ac- 
cordance with  Prof.  Meyer's  view,  the  ear  to  be  made  per- 

*  See  also  some  remarks,  and  the  drawings  of  the  ears  of  the  Lem- 
uroidea,  in  Messrs.  Murie  and  Mi vart's excellent  paper  in  "Transact. 
Zoolog.  Soc.,"  vol.  vii,  1869,  pp.  6  and  90. 

fUeber  das  Darwin'sche  Spitzohr,  "Archiv  fiir  Path.  Anat.  und 
Phys.,"  1871,  p.  485. 


Fig.  2.  Human  Ear,  mod- 
eled and  drawn  by  Mr. 
Woolner. 

a.  The  projecting  point. 


18  THE  DESCENT  OV  MAN,     ' 

feet  by  the  equal  development  of  the  cartilage  throughout 
the  whole  extent  of  the  margin,  it  would  have  covered  fully 
one-third  of  the  whole  ear.  Two  cases  have  been  commu- 
nicated to  me,  one  in  North  America  and  the  other  in 
England,  in  which  the  upper  margin  is  not  at  all  folded 
inward,  but  is  pointed,  so  that  it  closely  resembles  the 
pointed  ear  of  an  ordinary  quadruped  in  outline.  In  one 
of  these  cases,  which  was  that  of  a  young  child,  the  father 
compared  the  ear  with  the  drawing  which  I  have  given*  of 


Fig.  3.    Foetus  of  an  Orang.    Exact  copy  of  a  photograph,  showing 
the  form  of  the  ear  at  this  early  age. 

the  ear  of  a  monkey,  the  Cynopithecus  niger,  and  says  that 
their  outlines  are  closely  similar.  If,  in  these  two  case?, 
the  margin  had  been  folded  inward  in  the  normal  manner, 
an  inward  projection  must  have  been  formed.  I  may  add 
that  in  two  other  cases  the  outline  still  remains  somewhat 
pointed,  although  the  margin  of  the  upper  part  of  the  ear 
is  normally  folded  inward — in  one  of  them,  however,  very 
narrowly.  The  above  wood-cut  (Fig.  3)  is  an  accurate 
copy  of  a  photograph  of  the  foetus  of  an  orang  (iiindly  sent 
me  by  Dr.  Nitsche),  in  which  it  may  be  seen  how  different 
the  pointed  outline  of  the  ear  is  at  this  period  from  its 
adult  condition,  when  it  bears  a  close  general  resemblance 

*"The  Expression  of  the  Emotions,"  p.  136, 


RUDIMENTS.  19 

to  that  of  man.  It  is  evident  that  the  folding  over  of  the 
tip  of  such  an  ear,  unless  it  changed  greatly  during  its 
further  development,  would  give  rise  to  a  point  projecting 
inward.  On  the  whole,  it  still  seems  to  me  probable  that 
the  points  in  question  are  in  some  cases,  both  in  man  and 
apes,  vestiges  of  a  former  condition.  ** 

The  nictitating  membrane,  or  third  eyelid,  with  its  ac- 
cessor}^ muscles  and  other  structures,  is  especially  well 
developed  in  birds,  and  is  of  much  functional  importance 
to  them,  as  it  can  be  rapidly  drawn  across  the  whole  eye- 
ball. It  is  found  in  some  reptiles  and  amphibians,  and  in 
certain  fishes,  as  in  sharks.  It  is  fairly  well  developed  in 
the  two  lower  divisions  of  the  mammalian  series,  namely, 
in  the  monotremata  and  marsupials,  and  in  some  few  of 
the  higher  mammals,  as  in  the  walrus.  But  in  man,  the 
quadrumana,  and  most  other  mammals,  it  exists,  as  is  ad- 
mitted by  all  anatomists,  as  a  mere  iiidiment,  called  the 
semilunar  fold.* 

The  sense  of  smell  is  of  the  highest  importance  to  the 
greater  number  of  mammals — to  some,  as  the  ruminants,  in 
warning  them  of  danger;  to  others,  as  the  camivora,  in 
finding  their  prey;  to  others,  again,  as  the  wild  boar,  for 
both  purposes  combined.  But  the  sense  of  smell  is  of 
extremely  slight  service,  if  any,  even  to  the  dark  colored 
races  of  men,  in  whom  it  is  much  more  highly  develoj)ed 
than  in  the  white  and  civilized  races,  f  Nevertheless  it 
does  not  warn  them  of  danger,  nor  guide  them  to  their 

*Muller's  "Elements  of  Physiology,"  Eng.  translat.,  1842,  vol.  ii, 
p.  1117.  Owen,  "Anatomy  of  Vertebrates,"  vol.  iii,  p.  260;  ibid,  on 
the  Walrus,  "  Proc.  Zoolog.  Soc.,"  November  8,  1854.  See  also  R. 
Knox,  "Great  Artists  and  Anatomists,"  p.  106.  This  rudiment  ap- 
parently is  somewhat  larger  in  Negroes  and  Australians  than  in  Euro- 
peans, see  Carl  Vogt.  "  Lectures  on  Man,"  Eng.  translat.,  p.  129. 

f  The  account  given  by  Humboldt  of  the  power  of  smell  possessed 
by  the  natives  of  South  America  is  well  known,  and  has  been  con- 
firmed by  others,  M.  Houzeau  ("  Etudes  sur  les  Facultes  Mentales," 
etc.,  tom.  i,  1872,  p.  91)  asserts  that  he  repeatedly  made  experiments, 
and  proved  that  Negroes  and  Indians  could  recognize  persons  in  the 
dark  by  their  odor.  Dr.  W.  Ogle  has  made  some  curious  observa- 
tions on  the  connection  between  the  power  of  smell  and  the  coloring 
matter  of  the  mucous  membrane  of  the  olfactory  region,  as  well  as  of 
the  skin  of  the  body.  I  have,  therefore,  spoken  in  the  text  of  the 
dark  colored  races  having  a  finer  sense  of  smell  than  the  white  races. 
See  his  paper,  "  Medico-Chirurgical  Transactions,"  London,  vol.  liii, 
1870,  p.  276. 


20  THE  DESCENT  OF  MAN. 

food;  nor  does  it  prevent  the  Esquimaux  from  sleeping  in 
the  most  fetid  atmosphere,  nor  many  savages  from  eating 
half-putrid  meat.  In  Europeans  the  power  differs  greatly 
in  different  individuals,  as  I  am  assured  by  an  eminent 
naturalist  who  possesses  this  sense  highly  developed,  and 
who  has  attended  to  the  subject.  Those  who  believe  in  the 
principle  of  gradual  evolution,  will  not  readily  admit  that 
the  sense  of  smell  in  its  present  state  was  originally  acquired 
by  man  as  he  now  exists.  He  inherits  the  power  in  an 
enfeebled  and  so  far  rudimentary  condition,  from  some 
early  progenitor  to  whom  it  was  highly  serviceable,  and  by 
whom  it  was  continually  used.  In  those  animals  which 
have  this  sense  highly  developed,  such  as  dogs  and  horses, 
the  recollection  of  persons  and  of  places  is  strongly  associ- 
ated with  their  odor;  and  we  can  thus  perhaps  understand 
how  it  is,  as  Dr.  Maudsley  has  truly  remarked,*  that  the 
sense  of  smell  in  man  *^is  singularly  effective  in  recalling 
vividly  the  ideas  and  images  of  forgotten  scenes  and  places." 

Man  differs  conspicuously  from  all  the  other  Primates  in 
being  almost  naked.  But  a  few  short  straggling  hairs  are 
found  over  the  greater  part  of  the  body  in  the  man,  and 
fine  down  on  that  of  the  woman.  The  different  races  differ 
much  in  hairiness;  and  in  the  individuals  of  the  same  race 
the  hairs  are  highly  variable,  not  only  in  abundance,  but 
likewise  in  position;  thus  in  some  Europeans  the  shoulders 
are  quite  naked,  while  in  others  they  bear  thick  tufts  of 
hair.f  There  can  belittle  doubt  that  the  hairs  thus  scat- 
tered over  the  body  are  the  rudiments  of  the  uniform  hairy 
coat  of  the  lower  animals.  This  view  is  rendered  all  the 
more  probable,  as  it  is  known  that  fine,  short,  and  pale- 
colored  hairs  on  the  limbs  and  other  parts  of  the  body, 
occasionally  become  developed  into  ^^  thickset,  long,  and 
rather  coarse  dark  hairs,"  when  abnormally  nourished  near 
old-standing  inflamed  surfaces.  X 

I  am  informed  by  Sir  James  Paget  that  often  several 
members  of  a  family  have  a  few  hairs  in  their  eyebrows 
much   longer   than   the   others;   so  that  even   this   slight 

*  •'  The  Physiology  and  Pathology  of  Mind,"  2d  edit.,  1868,  p.  134. 

f  Eschricht,  Ueber  die  Richtung  der  Haare  am  menschlichen  Kor- 
per,  "Miiller's  Archiv  fur  Anat.  und  Phys.,"  1837,  s.  47.  I  shall 
often  have  to  refer  to  this  very  curious  paper. 

I  Paget,  "Lectures  on  Surgical  Pathology,"  1853,  vol.  i,  p.  71, 


ttUDIMENTS,  21 

peculiarity  seems  to  be  inherited.  These  hairs,  too,  seem 
to  have  their  representatives;  for  in  the  chimpanzee,  and  in 
certain  species  of  Macacus,  there  are  scattered  hairs  of  con- 
siderable length  rising  from  the  naked  skin  above  the  eyes, 
and  corresponding  to  our  eyebrows;  similar  long  hairs  pro- 
ject from  the  hairy  covering  of  the  superciliary  ridges  in 
some  baboons. 

The  fine  wool-like  hair,  or  so-called  lanugo,  with  which 
the  human  foetus  during  the  sixth  month  is  thickly  cov- 
ered, offers  a  more  curious  case.  It  is  first  developed,  dur- 
ing the  fifth  month,  on  the  eyebrows  and  face,  and  espe- 
cially round  the  mouth,  where  it  is  much  longer  than  that 
on  the  head.  A  mustache  of  this  kind  was  observed  by 
Esclmcht*  on  a  female  foetus;  but  this  is  not  so  surprising 
a  circumstance  as  it  may  at  first  appear,  for  the  two  sexes 
generally  resemble  each  other  in  all  external  characters 
during  an  early  period  of  growth.  The  direction  and 
arrangement  of  the  hairs  on  all  parts  of  the  foetal  body  are 
the  same  as  in  the  adult,  but  are  subject  to  much  varia- 
bility. The  whole  surface,  including  even  the  forehead 
and  ears,  is  thus  thickly  clothed;  but  it  is  a  significant  fact 
that  the  palms  of  the  hands  and  the  soles  of  the  feet  are 
quite  naked,  like  the  inferior  surfaces  of  all  four  extremi- 
ties in  most  of  the  lower  animals.  As  this  can  hardly  be 
an  accidental  coincidence,  the  woolly  covering  of  the  foetus 
probably  represents  the  first  permanent  coat  of  hair  in  those 
mammals  which  are  born  hairy.  Three  or  four  cases  have 
been  recorded  of  persons  born  with  their  whole  bodies  and 
faces  thickly  covered  with  fine  long  hairs;  and  this  strange 
condition  is  strongly  inherited,  and  is  correlated  with  an 
abnormal  condition  of  the  teeth,  f  Prof.  Alex.  Brandt  in- 
forms me  that  he  has  compared  the  hair  from  the  face  of  a 
man  thus  characterized,  aged  thirty-five,  with  the  lanugo 
of  a  foetus,  and  finds  it  quite  similar  in  texture;  therefore, 
as  he  remarks,  the  case  may  be  attributed  to  an  arrest  of 
development  in  the  hair,  together  with  its  continued 
growth.  Many  delicate  children,  as  I  have  been  assured 
by  a  surgeon  to  a  hospital  for  children,  have  their  backs 

* Eschriclit,  ibid.,  s.  40,  47. 

f  See  my  "Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  p.  327.  Prof.  Alex.  Brandt  has  recently  sent  me  an  additional 
case  of  a  father  and  son,  born  in  Russia,  with  these  peculiarities.  I 
have  received  drawings  of  both  from  Paris. 


22  THE  DESCENT  OF  MAN, 

covered  by  rather  long  silky  hairs;  and  such  cases  probably 
come  under  the  same  head. 

It  appears  as  if  tlie  posterior  molar  or  wisdom  teeth  were 
tending  to  become  rudimentary  in  the  more  civilized  races 
of  man.  These  teeth  are  rather  smaller  than  the  other 
molars,  as  is  likewise  the  case  with  the  corresponding  teeth 
in  the  chimpanzee  and  orang;  and  they  have  only  two 
separate  fangs.  They  do  not  cut  through  the  gums  till 
about  the  seventeenth  year,  and  I  have  been  assured  that 
they  are  much  more  liable  to  decay,  and  are  earlier  lost 
than  the  other  teeth;  but  this  is  denied  by  some  eminent 
dentists.  They  are  also  much  more  liable  to  vary,  both  in 
structure  and  in  the  period  of  their  development,  than  the 
other  teeth.*  In  the  Melanian  races,  on  the  other  hand, 
the  wisdom  teeth  are  usually  furnished  with  three  separate 
fangs,  and  are  generally  sound;  they  also  diifer  from  the 
other  molars  in  size,  less  than  in  the  Caucasian  races,  f 
Prof.  Schaaffhausen  accounts  for  this  difference  between 
the  races  by  '*  the  posterior  dental  portion  of  the  jaw  being 
always  shortened "  in  those  that  are  civilized,  |  and  this 
shortening  may,  I  presume,  be  attributed  to  civilized  men 
liabitually  feeding  on  soft,  cooked  food,  and  thus  using 
their  jaws  less.  I  am  informed  by  Mr.  Brace  that  it  is 
becoming  quite  a  common  practice  in  the  United  States  to 
remove  some  of  the  molar  teeth  of  children,  as  the  jaw 
does  not  grow  large  enough  for  the  perfect  development  of 
the  normal  number.  § 

With  respect  to  the  alimentary  canal,  I  have  met  with  an 
account  of  only  a  single  rudiment,  namely  the  vermiform 
appendage  of  the  caecum.  The  caecum  is  a  branch  or  diver- 
ticulum of  the  intestine,  ending  in  a  cul-de-sac,  and  is  ex- 
tremely long  in  many  of  the  lower  vegetable-feeding  mam- 

*  Dr.  Webb,  "Teeth  in  Man  and  the  Anthropoid  Apes,"  as  quoted 
by  Dr.  C.  Carter  Blake  in  "Anthropological  Review,"  July,  1867, 
p.  299. 

f  Owen,  "Anatomy  of  Vertebrates."  vol.  iii,  pp.  320,  321  and  325, 

X"On  the  Primitive  Form  of  the  Skull,"  Eng.  translat.  in"  Anthrop- 
ological Review,"  Oct.  1868,  p.  426. 

§  Prof.  Montegazza  writes  to  me  from  Florence,  that  he  has  lately 
been  studying  the  last  molar  teeth  in  the  different  races  of  man,  and 
has  come  to  the  same  conclusion  as  that  given  in  my  text,  viz. :  that 
in  the  higher  or  civilized  races  they  are  on  the  road  toward  atrophy 
or  elimination. 


RUDIMENTS.  23 

mals.  In  the  marsupial  koala  it  is  actually  more  than 
thrice  as  long  as  the  whole  body.*  It  is  sometimes  produced 
into  a  long  gradually  tapering  point,  and  is  sometimes  con- 
stricted in  parts.  It  appears  iis  if,  in  consequence  of 
changed  diet  or  habits,  the  caecum  had  become  much  short- 
ened in  various  animals,  the  vermiform  appendage  being 
left  as  a  rudiment  of  the  shortened  part.  That  this  ap- 
pendage is  a  rudiment,  we  may  infer  from  its  small  size,  and 
from  the  evidence  which  Prof.  Canestrini  \  has  collected  of  its 
variability  in  man.  It  is  occasionally  quite  absent,  or  again 
is  largely  developed.  The  passage  is  sometimes  completely 
closed  for  half  or  two-thirds  of  its  length,  with  the  terminal 
part  consisting  of  a  flattened  solid  expansion.  In  the  orang 
this  appendage  is  long  and  convoluted  :  in  man  it  arises 
from  the  end  of  the  short  caecum,  and  is  commonly  from 
four  to  five  inches  in  length,  being  only  about  the  third  of 
an  inch  in  diameter.  Not  only  is  it  useless,  but  it  is  some- 
times the  cause  of  death,  of  which  fact  I  have  lately  heard 
two  instances  :  this  is  due  to  small  hard  bodies,  such  as 
seeds,  entering  the  passage,  and  causing  inflammation.  \ 

In  some  of  the  lower  Quadrumana,  in  the  Lemuridae  and 
Carnivora,  as  well  as  in  many  marsupials,  there  is  a  pas- 
sage near  the  lower  end  of  the  humerus,  called  the  supra- 
condyloid  foramen,  through  which  the  great  nerve  of  the 
fore  limb  and  often  the  great  artery  pass.  Now  in  the 
humerus  of  man,  there  is  generally  a  trace  of  this  passage, 
which  is  sometimes  fairly  well  developed,  being  formed  by 
a  depending  hook-like  process  of  bone,  completed  by  a  band 
of  ligament.  Dr.  Struthers,  §  who  has  closely  attended  to 
the  subject,  has  now  shown  that  this  peculiarity  is  some- 
times inherited,  as  it  has  occurred  in  a  father,  and  in  no  less 

*Owen,  "  Anatomy  of  Vertebrates,"  vol.  iii,  pp.  416,  434,  441. 

f'Annuario  della  Soc.  d.  Nat.,"  Modena,  1867,  p.  94. 

:f  M.  C.  Martins  ("  De  I'Unite  Organique,"  in  "Revue  des  Deux 
Mondes,"  June  15,  1862,  p.  16),  and  Hackel  ("Generelle  Morpholo- 
gie,"  B.  ii,  s.  278),  have  both  remarked  on  the  singular  fact  of  this 
rudiment  sometimes  causing  death. 

§With  respect  to  inheritance,  see  Dr.  Struthers  in  the  "Lancet," 
Feb.  15,  1873,  and  another  important  paper,  ibid.,  Jan.  24,  1863,  p. 
83.  Dr.  Knox,  as  I  am  informed,  was  the  first  anatomist  who  drew 
attention  to  this  peculiar  structure  in  man  ;  see  his  "Great  Artists 
and  Anatomists,"  p.  63.  See  also  an  important  memoir  on  this  pro- 
cess by  Dr.  G  ruber,  in  the  "  Bulletin  de  I'Acad.  Imp.  de  St.  Peters- 
bourg,"  torn,  xii,  1867,  p.  448. 


24  THE  DESCENT  OF  MAN. 

than  four  out  of  his  seven  children.  When  present,  the 
great  nerve  invariably  passes  through  it ;  and  this  clearly 
indicates  that  it  is  the  homologue  and  rudiment  of  the 
supra-condyloid  foramen  of  the  lower  animals.  Prof. 
Turner  estimates,  as  he  informs  me,  that  it  occurs  in  about 
one  per  cent,  of  recent  skeletons.  But  if  the  occasional 
development  of  this  structure  in  man  is,  as  seems  probable, 
due  to  reversion,  it  is  a  return  to  a  very  ancient  state  of 
things,  because  in  the  higher  Quadrumana  it  is  absent. 

There  is  another  foramen  or  perforation  in  the  humerus, 
occasionally  present  in  man,  which  may  be  called  the  inter- 
condyloid.  This  occurs,  but  not  constantly,  in  various  an- 
thropoid and  other  apes,*  and  likewise  in  many  of  the  lower 
animals.  It  is  remarkable  that  this  perforation  seems  to 
have  been  present  in  man  much  more  frequently  during 
ancient  times  than  recently.  Mr.  Buskf  has  collected  the 
following  evidence  on  this  head:  Prof.  Broca  '''^noticed  the 
perforation  in  four  and  a  half  per  cent,  of  the  arm-bones 
collected  in  the  '  Cimetiere  du  Sud/  at  Paris;  and  in  the 
Grotto  of  Orrony,  the  contents  of  which  are  referred  to  the 
Bronze  period,  as  many  as  eight  humeri  out  of  thirty-two 
were  perforated ;  but  this  extraordinary  proportion,  he 
thinks,  might  be  due  to  the  cavern  having  been  a  sort  of 
^family  vault. ^  Again,  M.  Dupont  found  thirty  per  cent, 
of  perforated  bones  in  the  caves  of  the  Valley  of  the  Lesse, 
belonging  to  the  Reindeer  period;  while  M.  Leguay,  in  a 
sort  of  dobnen  at  Argenteuil,  observed  twenty-five  per  cent, 
to  be  perforated;  and  M.  Pruner-Bey  found  twenty-six  per 
cent,  in  the  same  condition  in  bones  from  Vaureal.  Nor 
should  it  be  left  unnoticed  that  M.  Pruner-Bey  states  that 
this  condition  is  common  in  Guanche  skeletons.^'  It  is  an 
interesting  fact  that  ancient  races,  in  this  and  several  other 
cases,  more  frequently  present  structures  which  resemble 
those  of  the  lower  animals  than  do  the  modern.  One  chief 
cause  seems  to  be  that  the  ancient  races  stand  somewhat 

*Mr.  St.  George  Mivart,  ''Transact.  Phil.  Soc,"  1867,  p.  310. 

f  " On  the  Caves  of  Gibraltar,"  "Transact.  Internat.  Congress  of 
Prehist.  Arcli."  Third  Session,  1869,  p.  159.  Prof  Wyman  has  lately 
shown  (Fourth  Annual  Report,  Peabody  Museum,  1871,  p.  20),  that 
this  perforation  is  present  in  thirty-one  per  cent,  of  some  human  re- 
mains from  ancient  mounds  in  the  Western  United  States,  and  in 
Florida.     It  frequently  occurs  in  the  negro. 


1 


RUDIMENTS.  25 

nearer  in  the  long  line  of  descent  to  their  remote  animal- 
like progenitors. 

In  man,  the  os  coccyx,  together  with  certain  other  verte- 
brae hereafter  to  be  described,  though  f unctionless  as  a  tail, 
plainly  represent  this  part  in  other  vertebrate  animals.  At 
an  early  embryonic  period  it  is  free,  and  projects  beyond 
the  lower  extremities;  as  may  be  seen  in  the  drawing  (Fig. 
1)  of  a  human  embryo.  Even  after  birth  it  has  been  known, 
in  certain  rare  and  anomalous  cases,*  to  form  a  small  ex- 
ternal rudiment  of  a  tail.  The  os  coccyx  is  short,  usually 
including  only  four  vertebrae,  all  anchylosed  together;  and 
these  are  in  a  rudimentary  condition,  for  they  consist,  with 
the  exception  of  the  basal  one,  of  the  centrum  alone,  f 
They  are  furnished  with  some  small  muscles;  one  of  which, 
as  I  am  informed  by  Prof.  Turner,  has  been  expressly  de- 
scribed by  Theile  as  a  rudimentary  repetition  of  the  exten- 
sor of  the  tail,  a  muscle  which  is  so  largely  developed  in 
many  mammals. 

The  spinal  cord  in  man  extends  only  as  far  downward  as 
the  last  dorsal  or  first  lumbar  vertebra;  but  a  thread-like 
structure  (the  fihim  terminale)  runs  down  the  axis  of  the 
sacral  part  of  the  spinal  canal,  and  even  along  the  back  of 
the  coccygeal  bones.  The  upper  part  of  this  filament,  as 
Prof.  Turner  informs  me,  is  undoubtedly  homologous  with 
the  spinal  cord ;  but  the  lower  part  apparently  consists  merely 
of  the  j)i(^  mater,  or  vascular  investing  membrane.  Even 
in  this  case  the  os  coccyx  may  be  said  to  possess  a  ves- 
tige of  so  important  a  structure  as  the  spinal  cord,  though 
no  longer  inclosed  within  a  bony  canal.  The  following 
fact,  for  which  I  am  also  indebted  to  Prof.  Turner, 
shows  how  closely  the  os  coccyx  corresponds  with  the 
true  tail  in  the  lower  animals:  Luschka  has  recently  dis- 
covered at  the  extremity  of  the  coccygeal  bones  a  very  pe- 
culiar convoluted  body,  which  is  continuous  with  the  mid- 
dle sacral  artery;  and  this  discovery  led  Krause  and  Meyer 

*Quatrefages  has  lately  collected  the  evidence  on  this  subject. 
"  Revue  des  Cours  Scientifiques,"  1867-1868,  p.  625.  In  1840  Fleisch- 
luann  exhibited  a  human  foetus  bearing  a  free  tail,  which,  as  is  not 
always  the  case,  included  vertebral  bodies;  and  this  tail  was  critically 
examined  by  the  many  anatomists  present  at  the  meeting  of  natural- 
ists at  Erlangen  (see  Marshall  in ' '  Niederlandischen  Archiv  fiir  Zoolo- 
gie,"  December,  1871). 

f  Owen,  "  On  the  Nature  of  Limbs,"  1849,  p.  114. 


26  THE  DESCENT  OF  MAN. 

to  examine  the  tail  of  a  monkey  (Macaciis),  and  of  a  cat, 
in  both  of  which  they  found  a  simihirly  convoluted  body, 
though  not  at  the  extremity. 

The  reproductive  system  offers  various  rudimentary  struct- 
ures; but  these  differ  in  one  important  respect  from  the 
foregoing  cases.  Here  we  are  not  concerned  with  the  ves- 
tige of  a  part  which  does  not  belong  to  the  species  in 
an  efficient  state,  but  with  a  part  efficient  in  the  one 
sex,  and  represented  in  the  other  by  a  mere  rudiment. 
Nevertheless,  the  occurrence  of  such  rudiments  is  as  diffi- 
cult to  explain,  on  -the  belief  of  the  separate  creation  of 
each  species,  as  in  the  foregoing  cases.  Hereafter  I  shall 
have  to  recur  to  these  rudiments,  and  shall  show  that  their 
presence  generally  depends  merely  on  inheritance,  that  is, 
on  parts  acquired  by  one  sex  having  been  partially  trans- 
mitted to  the  other.  I  will  in  this  place  only  give  some  in- 
stances of  such  rudiments.  It  is  well  known  that  in  the 
males  of  all  mammals,  including  man,  rudimentary  mammae 
exist.  These  in  several  instances  have  become  well  de- 
veloped, and  have  yielded  a  copious  supply  of  milk.  Their 
essential  identity  in  the  two  sexes  is  likewise  shown  by 
their  occasional  sympathetic  enlargement  in  both  during 
an  attack  of  the  measles.  The  vesicula  pro.statica,  wbich 
has  been  observed  in  many  male  mammals,  is  now  universally 
acknowledged  to  be  the  homogue  of  tlie  female  uterus, 
together  with  the  connected  pasFage.  It  is  impossible  to 
read  Leuckai't's  al»le  description  of  this  organ,  and  his 
reasoning,  without  admitting  the  justness  of  his  conclusion. 
Tliis  is  especially  clear  in  tbe  case  of  those  mammals  in 
which  the  true  ft^male  uterus  bifurcates,  for  in  the  males  of 
tliese  the  vesicula  likewise  bifurcates.*  Some  other  rudi- 
mentary structures  Ijelonging  to  the  reproductive  system 
might  have  been  here  adduced. f 

The  bearing  of  the  three  great  classes  of  facts  now  given 
is  unmistakable.  But  it  would  be  superfluous  fully  to  recap- 
itulate the  line  of  argument  given  in  detail  in  my  "  Origin 
of  Species."     The  homological  construction  of  the  whole 

*Leuckart,  in  Todd's  "  Cyclop,  of  Anat.."  1849-52,  vol.  iv,  ]).  1415. 
In  man  this  organ  is  only  from  three  to  six  lines  in  length,  bnt,  like 
so  many  other  rudimentary  parts,  it  is  variable  in  development  as 
well  as  in  other  characters. 

f  See,  on  this  subject,  Owen,  "Anatomy  of  Vertebrates,"  vol.  iii, 
pp.  675,  676,  706. 


RUDIMENTS.  27 

frame  in  the  members  of  the  same  class  is  intelligible,  if  we 
admit  their  descent  from  a  common  progenitor,  together 
with  their  subsequent  adaptation  to  diversified  conditions. 
On  any  other  view,  the  similarity  of  pattern  between  the 
hand  of  a  man  or  monkey,  the  foot  of  a  horse,  the  flipper 
of  a  seal,  the  wing  of  a  bat,  etc.,  is  utterly  inexplicable.* 
It  is  no  scientific  explanation  to  assert  that  they  have  all 
been  formed  on  the  same  ideal  plan.  With  respect  to  de- 
velopment, we  can  clearly  understand,  on  the  principle  of 
variations  supervening  at  a  i-ather  late  embryonic  period, 
:  and  being  inherited  at  a  corresponding  period,  how  it  is 
that  the  embryos  of  wonderfully  different  forms  should  still 
retain,  more  or  less  perfectly,  the  structure  of  their  common 
progenitor.  No  other  explanation  has  ever  been  given  of 
the  marvelous  fact  that  the  embryos  of  a  man,  dog,  seal, 
bat,  reptile,  etc.,  can  at  first  hardly  be  distinguished  from 
each  other.  In  order  to  understand  the  existence  of  rudi- 
mentary organs,  we  have  only  to  suppose  that  a  former  pro- 
genitor possessed  the  parts  in  question  in  a  perfect  state, 
:and  that  under  changed  habits  of  life  they  became  greatly 
reduced,  either  from  simple  disuse,  or  through  the  natural 
selection  of  those  individuals  which  were  least  encumbered 
with  a  superfluous  part,  aided  by  the  other  means  pre- 
viously indicated. 

*  Prof.  Bianconi,  in  a  recently  published  work,  illustrated  by  ad- 
mirable engravings  ("La  Theorie  Darwinienne  et  la  creation  dite  in- 
dependante,"  1874),  endeavors  to  show  that  bomological  structures, 
in  the  above  and  other  cases,  can  be  fully  explained  on  mechanical 
principles,  in  accordance  with  their  uses.  No  one  has  shown  so  well, 
bow  admirably  such  structures  are  adapted  for  their  final  purpose  ; 
and  this  adaptation  can,  as  I  believe,  be  explained  through  natural 
selection.  In  considering  the  wing  of  a  bat,  he  brings  forward  (p. 
218)  what  appears  to  me  (to  use  Auguste  Comte's  words)  a  mere  met- 
aphysical principle,  namely,  the  preservation  "in  its  integrity  of  the 
mammalian  nature  of  the  animal."  In  only  a  few  cases  does  he  dis- 
cuss rudiments,  and  then  only  those  parts  which  are  partially 
rudimentary,  such  as  the  little  hoofs  of  the  pig  and  ox,  which  do  not 
touch  the  ground  ;  these  he  shows  clearly  to  be  of  service  to  the  ani- 
mal. It  is  unfortunate  that  he  did  not  consider  such  cases  as  the 
minute  teeth,  which  never  cut  through  the  jaw  in  the  ox,  or  the 
mammae  of  male  quadrupeds,  or  the  wings  of  certain  beetles,  existing 
under  the  soldered  wing-covers,  or  the  vestiges  of  the  pistil  and 
£tamens  in  various  flowers,  and  many  other  such  cases.  Although  I 
_greatly  admire  Prof.  Bianconi 's  work,  yet  the  belief  now  held  by 
most  naturalists  seems  to  me  left  unshaken,  that  homological  struct- 
ures are  inexplicable  on  the  principle  of  mere  adaptation.    . 


28  THE  DESCENT  OF  MAN, 

Thus  we  can  understand  how  it  has  come  to  pass  that 
man  and  all  other  vertebrate  animals  have  been  con- 
structed on  the  same  general  model,  why  they  pass  througli 
the  same  early  stages  of  development,  and  why  they  retain 
certain  rudiments  in  common.  Consequently  we  ought 
frankly  to  admit  their  community  of  descent ;  to  take  any 
other  view,  is  to  admit  that  our  own  structure,  and  that  of 
all  the  animals  around  us,  is  a  mere  snare  to  entrap  our 
judgment.  This  conclusion  is  greatly  strengthened,  if  we 
look  to  the  members  of  the  whole  animal  series,  and  con- 
sider the  evidence  derived  from  their  affinities  or  classifica- 
tion, their  geographical  distribution  and  geological  succes- 
sion. It  is  only  our  natural  prejudice,  and  that  arrogance 
which  made  our  forefathers  declare  that  they  were  de- 
scended from  demi-gods,  which  leads  us  to  demur  to  this 
conclusion.  But  the  time  will  before  long  come,  when  it 
will  be  thought  wonderful  that  naturalists,  who  were  well 
acquainted  with  the  comparative  structure  and  development 
of  man,  and  other  mammals,  should  have  believed  that 
each  was  the  work  of  a  separate  act  of  creation. 


MANNER  OF  DEVELOPMENT.  29 


CHAPTER  II. 

0^    THE  MAIfNER  OF   DEVELOPMENT    OF  MAN   FEOM    SOME 
LOWER  FORM. 

Variability  of  body  and  mind  in  man — Inlieritance — Causes  of  varia- 
bility— Laws  of  variation  the  same  in  man  as  in  the  lower  ani- 
mals— Direct  action  of  the  conditions  of  life — Effects  of  the 
increased  use  and  disuse  of  parts  —  Arrested  development  — 
Reversion  —  Correlated  variation  —  Rate  of  increase  —  Checks  to 
increase — Natural  selection — Man  the  most  dominant  animal  in 
the  world — Importance  of  his  coporeal  structure — The  causes 
which  have  led  to  his  becoming  erect — Consequent  changes  of 
structure — Decrease  in  size  of  the  canine  teeth — Increased  size 
and  altered  shape  of  the  skull — Nakedness — Absence  of  a  tail — 
Defenceless  condition  of  man. 

It  is  manifest  that  man  is  now  subject  to  much  variabil- 
ity. No  two  individuals  of  the  same  race  are  quite  alike. 
AVe  may  compare  millions  of  faces,  and  each  will  be  dis- 
tinct. There  is  an  equally  great  amount  of  diversity  in  the 
proportions  and  dimensions  of  the  various  parts  of  the  body; 
the  length  of  the  legs  being  one  of  the  most  variable  points.* 
Although  in  some  quarters  of  the  world  an  elongated  skull, 
and  in  other  quarters  a  short  skull  prevails,  yet  there  is 
great  diversity  of  shape  even  within  the  limits  of  the  same 
race,  as  with  the  aborigines  of  America  and  South  Australia 
— the  latter  a  race  ^'^  probably  as  pure  and  homogeneous  in 
blood,  customs,  and  language  as  any  in  existence" — and 
even  with  the  inhabitants  of  so  confined  an  area  as  the 
Sandwich  Islands,  f     An  eminent  dentist  assures  me  that 

*  "  Investigations  in  Military  and  Anthropolog.  Statistics  of  Ameri- 
can Soldiers,"  by  B.  A.  Gould,  1869,  p.  256. 

f  With  respect  to  the  "  Cranial  forms  of  the  American  Aborigines," 
see  Dr.  Aitken  Meigs  in  "  Proc.  Acad.  Nat.  Sci.,"  Philadelphia,  May, 
1868.  On  the  Australians,  see  Huxley,  in  Lyell's  "Antiquity  of 
ISIan,"  1868,  p.  87.  On  the  Sandwich  Islanders,  Prof.  J.  Wyman, 
"Observations  oji  Crania,"  Boston,  1868,  p.  1§, 


30  THE  DESCENT  OF  MAN. 

there  is  nearly  as  much  diversity  in  the  teeth  as  in  the  feat- 
ures. The  chief  arteries  so  frequently  run  in  abnormal 
courses,  that  it  has  been  found  useful  for  surgical  purposes 
to  calculate  from  1040  corpses  how  often  each  course  pre- 
vails.* The  muscles  are  eminently  variable  :  thus  those  of 
the  foot  were  found  by  Prof.  Turner  f  not  to  be  strictly 
alike  in  any  two  out  of  fifty  bodies ;  and  in  some  the  de- 
viations were  considerable.  He  adds,  that  the  power  of 
performing  the  appropriate  movements  must  have  been 
modified  in  accordance  with  the  several  deviations.  Mr. 
J.  Wood  has  recorded  \  the  occurrence  of  295  muscular 
variations  in  thirty-six  subjects,  and  in  another  set  of  the 
same  number  no  less  than  558  variations,  those  occurring 
on  both  sides  of  the  body  being  only  reckoned  as  one.  In 
the  last  set,  not  one  body  out  of  the  thirty-six  was  '^  found 
totally  wanting  in  departures  from  the  standard  descrip- 
tions of  the  muscular  system  given  in  anatomical  text 
books. ''^  A  single  body  presented  the  extraordinary  num- 
ber of  twenty-five  distinct  abnormalities.  The  same  mus- 
cle sometimes  varies  in  many  ways  :  thus  Prof.  Macalister 
describes  §  no  less  than  twenty  distinct  variations  in  the 
palmaris  accessorius. 

The  famous  old  anatomist,  Wolff,  ||  insists  that  the  inter- 
nal viscera  are  more  variable  than  the  external  parts:  NuUa 
'particula  est  qum  non  aliter  et  aliter  in  aliis  se  liabeat 
homi7iil)us.  He  has  even  written  a  treatise  on  the  choice 
of  typical  examples  of  the  viscera  for  representation.  A 
discussion  on  the  beau-ideal  of  the  liver,  lungs,  kidneys, 
etc.,  as  of  the  human  face  divine,  sounds  strange  in  our 
ears. 

The  variability  or  diversity  of  the  mental  faculties  in 
men  of  the  same  race,  not  to  mention  the  greater  differ- 
ences between  the  men  of  distinct  races,  is  so  notorious  that, 
not  a  word  need  here  be  said.  So  it  is  with  the  lower  ani- 
mals. All  who  have  had  charge  of  menageries  admit  this 
fact,  and  we  see  it  plainly  in  our  dogs  and  other  domestic 

*  "Anatomy  of  the  Arteries,"  by  R.  Quain.     Preface,  vol.  i,  1844. 
f  "  Transact.  Royal  Soc.  Edinburgh,"  vol.  xxiv,  pp.  175,  189. 
X  "  Proc.  Royal  Soc,"  1867,  p.  544  ;  also  1868,  pp.  483,  534.    There 
Is  a  previous  paper,  1866,  p.  229. 

§"Proc.  R.  Irish  Academy,"  vol.  x,  1868,  p.  141. 
I  "  Act,  Acftd.  gt.  P^tersbur^,"  1778,  part  ii,  p.  217. 


MANNER  OF  DEVELOPMENT.  31 

animals.  Brehm  especially  insists  that  each  individual 
monkey  of  those  which  he  kept  tame  in  Africa  had  its  own 
peculiar  disposition  and  tamper:  he  mentions  one  baboon 
remarkable  for  its  high  intelligence;  and  the  keepere  in  the 
Zoological  Gardens  pointed  out  to  me  a  monkey,  belonging 
to  the  New  World  division,  equally  remarkable  for  intelli- 
gence. Rengger,  also,  insists  on  the  diversity  in  the  vari- 
ous mental  characters  of  the  monkeys  of  the  same  species 
which  he  kept  in  Paraguay;  and  this  diversity,  as  he  adds, 
is  partly  innate,  and  partly  the  result  of  the  manner  in 
which  they  have  been  treated  or  educated.* 

I  have  elsewhere  f  so  fully  discussed  the  subject  of  In- 
heritance, that  I  need  here  add  hardly  any  thing.  A 
greater  number  of  facts  have  been  collected  with  respect  to 
the  transmission  of  the  most  tiifling,  as  well  as  of  the  most 
important  characters  in  man,  than  in  any  of  the  lower  ani- 
mals; though  the  facts  are  copious  enough  with  respect  to 
the  latter.  So  in  regard  to  mental  qualities,  their  trans- 
mission is  manifest  in  our  dogs,  horses,  and  other  domestic 
animals.  Besides  special  tastes  and  habits,  general  intelli- 
gence, courage,  bad  and  good  temper,  etc.,  are  certainly 
transmitted.  With  man  we  see  similar  facts  in  almost 
every  family ;  and  we  now  know,  through  the  admirable 
labors  of  Mr.  GaltonJ  that  genius  which  implies  a  wonder- 
fully complex  combination  of  high  faculties,  tends  to  be 
inherited;  and,  on  the  other  hand,  it  is  too  certain  that  in- 
sanity and  deteriorated  mental  powers  likewise  run  in 
families. 

With  respect  to  the  causes  of  variability,  we  are  in  all 
cases  very  ignorant;  but  we  can  see  that  in  man  as  in  the 
lower  animals,  they  stand  in  some  relation  te  the  conditions 
to  which  each  species  has  been  exposed  during  several  gen- 
erations. Domesticated  animals  vary  more  than  those  in  a 
state  of  nature;  and  this  is  apparenth'  due  te  the  diversified 
and  changing  nature  of  the  conditions  to  which  they  have 
been  subjected.     In  this  resi:>ect  the  different  races  of  man 

*  Brehm,  "  Thierleben,"  B,  i,  s.  58,  87.  Rengger,  **  Saugethiere 
von  Paraguay,"  s.  57. 

f  "Variation  of  Animals  and  Plants  under  Domestication,"  vol.  ii, 
chap.  xii. 

1  "  Hereditary  Genius:  an  Inquiry  into  its  Laws  and  Conse- 
quences," 1869. 


32  THE  DESCENT  OF  MAN, 

resemble  domesticated  animals,  and  so  do  the  individuals 
I  of  the  same  race,  when  inhabiting  a  very  wide  area,  like 
tiiat  of  America.  We  see  the  influence  of  4ii;^5siti|dw)^- 
djtions  in  the  more  civilized  nations;  for  the  memBerToe- 
longmg  to  different  grades  of  rank,  and  following  different 
occupations,  present  a  greater  range  of  character  than  do 
the  members  of  barbarous  nations.  But  the  uniformity  of 
savages  has  often  been  exaggerated,  and  in  some  cases  can 
hardly  be  said  to  exist.*  It  is,  nevertheless,  an  error  to 
speak  of  man,  even  if  we  look  only  to  the  conditions  to 
which  he  has  been  exposed,  as  "far  more  domesticated"! 
than  any  other  animal.  Some  savage  races,  such  as  the 
Australians,  are  not  exposed  to  more  diversified  conditions 
than  are  many  species  which  have  a  wide  range.  In  an- 
other and  much  more  important  respect,  man  differs  widely 
from  any  strictly  domesticated  animal;  for  his  breeding  has 
never  long  been  controlled,  either  by  methodical  or  uncon- 
scious selection.  No  race  or  body  of  men  has  been  so  com- 
pletely subjugated  by  other  men,  as  that  certain  individuals 
should  be  preserved,  and  thus  unconsciously  selected,  from 
somehow  excelling  in  utility  to  their  masters.  Nor  have 
certain  male  and  female  individuals  been  intentionally 
picked  out  and  matched,  except  in  the  well-known  case  of 
the  Prussian  grenadiers;  and  in  this  case  man  obeyed,  as 
might  have  been  expected,  the  law  of  methodical  selection; 
for  it  is  asserted  that  many  tall  men  were  reared  in  the 
villages  inhabited  by  the  grenadiers  and  their  tall  wives. 
In  Sparta,  also,  a  form  of  selection  was  followed,  for  it  was 
enacted  that  all  children  should  be  examined  shortly  after 
birth;  the  well-formed  and  vigorous  being  preserved,  the 
others  left  to  perish.  | 

*Mr.  Bates  remarks  (*'  The  Naturalist  on  the  Amazons,"  1863,  vol. 
ii,  p.  159),  with  respect  to  the  Indians  of  the  same  South  American 
tribe,  "  No  two  of  them  were  at  all  similar  in  the  shape  of  the  head  ; 
one  man  had  an  oval  visage  with  fine  features,  and  another  was 
quite  Mongolian  in  breadth  and  prominence  of  cheek,  spread  of  nos- 
trils, and  obliquity  of  eyes." 

f  Blumenbach,  "  Treatises  on  Anthropolog.,"  Eng.  translat.,  1865, 
p.  205. 

:}:Mitford's  "History  of  Greece,"  vol.  i,  p.  282.  It  appears  also 
from  a  passage  in  Xenophon's  "Memorabilia,"  B.  ii,  4  (to  which  my 
attention  has  been  called  by  the  Kev.  J.  N.  Hoare),  that  it  was  a  well 
recognized  principle  with  the  (J reeks,  that  men  ought  to  select  their 
wives  with  9f  view  to  the  health  and  vigor  of  their  children.     The 


MANNER  OF  DEVELOPMENT.  33 

If  we  consider  all  the  races  of  man  as  forming  a  single 
species,  his  range  is  enormous;  but  some  separate  races,  as 
the  Americans  and  Polynesians,  have  very  wide  ranges.  It 
is  a  well-known  law  that  widely  ranging  species  are  much 
more  variable  than  species  with  restricted  ranges;  and  the 
variability  of  many  may  with  more  truth  be  compared  with 
that  of  widely  ranging  species,  than  with  that  of  domesti- 
cated animals. 

Not  only  does  variability  appear  to  be  induced  in  man 
and  the  lower  animals  by  the  same  general  causes,  but  in 
both  the  same  parts  of  the  body  are  affected  in  a  closely 
analogous  manner.  This  has  been  proved  in  such  full  de- 
tail by  Godron  and  Quatrefages,  that  I  need  here  only  refer 
to  their  works.*  Monstrosities,  which  graduate  into  slight 
variations,  are  likewise  so  similar  in  man  and  the  lower 
animals,  that  the  same  classification  and  the  same  terms 
can  be  used  for  both,  as  has  been  shown  by  Isidore  Geoffrey 
St.-Hilaire.f  In  my  work  on  the  variation  of  domestic 
animals,  I  have  attempted  to  arrange  in  a  rude  fashion  the 
laws  of  variation  under  the  following  heads  :  The  direct 
and  definite  action  of  changed  conditions,  as  exhibited  by 

Grecian  poet,  Theognis,  who  lived  550  B.C.,  clearly  saw  how  import- 
ant selection,  if  carefully  applied,  would  be  for  the  improvement  of 
mankind.  He  saw,  likewise,  that  wealth  often  checks  the  proper 
action  of  sexual  selection.     He  thus  writes  : 

**  With  kine  and  horses,  Kurnus!  we  proceed 
By  reasonable  rules,  and  choose  a  breed 
For  profit  and  increase,  at  any  price; 
Of  a  sound  stock,  without  defect  or  vice. 
But,  in  the  daily  matches  that  we  make, 
The  price  is  every  thing:  for  money's  sake, 
Men  marry:  women  are  in  marriage  given 
The  churl  or  ruffian,  that  in  wealth  has  thriven. 
May  match  his  offspring  with  the  proudest  race: 
Thus  every  thing  is  mix'd,  noble  and  base! 
If  then  in  outward  manner,  form,  and  mind. 
You  find  us  a  degraded,  motley  kind, 
Wonder  no  more,  my  friend!  the  cause  is  plain. 
And  to  lament  the  consequence  is  vain." 
(The  works  of  J.  Hookham  Frere,  vol.  ii.  1872,  p.  334.) 

♦Godron,  "  De  I'Espece,"  1859,  torn,  ii,  livre  3.  Quatrefages, 
"  Unite  de  I'Espece  Humaine,"  1861.  Also  Lectures  on  Anthropol- 
ogy, given  in  the  "Revue  des  Cours  Scientifiques,"  1866-1868. 

t  "  Hist.  Gen.  et  Part,  des  Anomalies  de  I'Organisation,"  in  three 
volumes,  tom.  i,  1833. 


34  THE  DESCENT  OF  MAN. 

all  or  nearly  all  the  individuals  of  the  same  species,  varying 
in  the  same  manner  under  the  same  circumstances.  The 
effects  of  the  long-continued  use  or  disuse  of  parts.  The 
cohesion  of  homologous  parts.  The  variability  of  multiple 
[)arts.  Compensation  of  growth  ;  but  of  this  law  I  have 
found  no  good  instance  in  the  case  of  man.  The  effects  of 
the  mechanical  pressure  of  one  part  on  another;  as  of  the 
pelvis  on  the  cranium  of  the  infant  in  the  womb.  Arrests 
of  development,  leading  to  the  diminution  or  suppression 
of  parts.  The  reappearance  of  long-lost  characters  through 
reversion.  And  lastly,  correlated  variation.  And  these 
so-called  laws  apply  equally  to  man  and  the  lower  animals  ; 
and  most  of  them  even  to  plants.  It  would  be  superfluous 
here  to  discuss  all  of  them;  *  but  several  are  so  important, 
that  they  must  be  treated  at  considerable  length. 

Tlie  Direct  and  Definite  Action  of  Changed  Conditions. — 
This  is  a  most  perplexing  subject.  It  cannot  be  denied 
that  changed  conditions  produce  some,  and  occasionally  a 
considerable  effect,  on  organisms  of  all  kinds;  and  it  seems 
at  first  probable  that  if  sufficient  time  were  allowed  this 
would  be  the  invariable  result.  But  I  have  failed  to  obtain 
clear  evidence  in  favor  of  this  conclusion;  and  valid  reasons 
may  be  urged  on  the  other  side,  at  least  as  far  as  the  in- 
numerable structures  are  concerned  which  are  adapted  for 
special  ends.  There  can,  however,  be  no  doubt  that 
changed  conditions  induce  an  almost  indefinite  amount  of 
fluctuating  variability,  by  which  the  whole  organization  is 
rendered  in  some  degree  plastic. 

In  the  United  States,  above  1,000,000  soldiers,  who 
served  in  the  late  war,  were  measured,  and  the  States  in 
which  they  were  born  and  reared  were  recorded.  \  From 
this  astonishing  number  of  observations  it  is  proved  tluit 
local  influences  of  some  kind  act  directly  on  stature;  and 
we  further  learn  that  ^^  the  State  where  the  physical  growth 
has  in  great  measure  taken  place,  and  the  State  of  birth, 

*  I  have  fully  discussed  these  laws  in  my  "Variation  of  Animals 
and  Plants  under  Domestication,"  vol.  ii,  cliap.  xxii  and  xxiii.  M.  J, 
P.  Durand  has  lately  (1868)  published  a  valuable  essay  "  De  I'lnflu- 
ence  des  Milieux,"  etc.  He  lays  much  stress,  in  the  case  of  plants, 
on  the  nature  of  the  soil. 

f  "  Investigations  in  Military  and  Anthrop.  Statistics,"  etc.,  1869, 
by  B.  A.  Gould,  pp.  93,  107,  126,  131.  134, 


MANNER  OF  DEVELOPMENT.  35 

which  indicates  the  ancestry,  seem  to  exert  a  marked  in- 
fluence on  the  stature."  For  instance,  it  is  established, 
"*  that  residence  in  the  Western  States,  during  the  years  of 
growth,  tends  to  produce  increase  of  stature."  On  the 
other  hand,  it  is  certain  that  with  sailors,  their  life  delays 
growth,  as  shown  "by  the  great  difference  between  the 
statures  of  soldiers  and  sailors  at  the  ages  of  seventeen  and 
eighteen  years."  Mr.  B.  A.  Gould  endeavored  to  ascertain 
the  nature  of  the  influences  which  thus  act  on  stature;  but 
he  arrived  only  at  negative  results,  namely,  that  they  did 
not  relate  to  climate,  the  elevation  of  the  land,  soil,  nor 
even  '^^in  any  controlling  degree"  to  the  abundance  or  the 
need  of  the  comforts  of  life.  This  latter  conclusion  is 
directly  opposed  to  that  arrived  at  by  Villerme,  from  the 
statistics  of  the  height  of  the  conscripts  in  different  parts 
of  France.  AVhen  we  compare  the  differences  in  stature 
between  the  Polynesian  chiefs  and  the  lower  orders  within 
the  same  islands,  or  between  the  inhabitants  of  the  fertile 
volcanic  and  low  barren  coral  islands  of  the  same  ocean,* 
or  again  between  the  Fuegians  on  the  eastern  and  western 
shores  of  their  country,  where  the  means  of  subsistence  are 
very  different,  it  is  scarcely  possible  to  avoid  the  conclusion 
that  better  food  and  greater  comfort  do  influence  stature. 
But  the  preceding  statements  show  how  difficult  it  is  to 
arrive  at  any  precise  result.  Dr.  Beddoe  has  lately  proved 
that,  with  the  inhabitants  of  Britain,  residence  in  towns 
and  certain  occupations  have  a  deteriorating  influence  on 
height;  and  he  infers  that  the  result  is  to  a  certain  extent 
inherited,  as  is  likewise  the  case  in  the  United  States.  Dr. 
Beddoe  further  believes  that  wherever  a  *^  race  attains  its 
maximum  of  physical  development,  it  rises  highest  in 
energy  and  moral  vigor,  "f 

Whether  external  conditions  produce  any  other  direct 
effect  on  man  is  not  known.  It  might  have  been  expected 
that  differences  of  climate  would  have  had  a  marked  influ- 
ence, inasmuch  as  the  lungs  and  kidneys  are  brought  into 

*For  the  Polynesians,  see  Prichard's  "Physical  Hist,  of  Man- 
kind," vol.  V,  1847,  pp.  145,  283.  Also  Godron*  "  De  I'Espece,"  lom. 
ii,  p.  289.  There  is  also  a  remarkable  difference  in  appearance  be- 
tween the  closely  allied  Hindoos  inhabiting  the  Upper  Ganges  and 
Bengal  ;  see  Elphinstone's  "History  of  India,"  vol.  i,  p.  324. 

f  "  Memoirs,  Anthropolog.  Soc.,"  vol.  iii,  1867-69,  pp.  561,  565, 
567. 


36  THE  DESCENT  OF  MAN. 

activity  under  a  low  temperature,  and  the  liver  and  skin 
under  a  high  one.*  It  was  formerly  thought  that  the  color 
of  the  skin  and  the  character  of  the  hair  were  determined 
by  light  or  heat;  and  although  it  can  hardly  be  denied  that 
some  eif  ect  is  thus  produced,  almost  all  observers  now  agree 
that  the  effect  has  been  very  small,  even  after  exposure 
during  many  ages.  But  this  subject  will  be  more  properly 
discussed  when  we  treat  of  the  different  races  of  mankind. 
With  our  domestic  animals  there  are  grounds  for  believing 
that  cold  and  damp  directly  affect  the  growth  of  the  hair; 
but  I  have  not  met  with  any  evidence  on  this  head  in  the 
case  of  man. 

Effects  of  the  Increased  Use  and  Disuse  of  Parts. — It  is 
well  known  that  use  strengthens  the  muscles  in  the  individ- 
ual, and  complete  disuse,  or  the  destruction  of  the  proper 
nerve,  weakens  them.  AVhen  the  eye  is  destroyed,  the  optic 
nerve  often  becomes  atrophied.  When  an  artery  is  tied, 
the  lateral  channels  increase  not  only  in  diameter,  but  in 
the  thickness  and  strength  of  their  coats.  When  one  kid- 
ney ceases  to  act  from  disease,  the  other  increases  in  size, 
and  does  double  work.  Bones  increase  not  only  in  thick- 
ness, but  in  length,  from  carrying  a  greater  weight.  \  Dif- 
ferent occupations,  habitually  followed,  lead  to  changed 
proportions  in  various  parts  of  the  body.  Thus  it  was  as- 
certained by  the  United  States  Commission];  that  the  legs 
of  the  sailors  employed  in  the  late  war  were  longer  by  0.217 
of  an  inch  than  those  of  the  soldiers,  though  the  sailors 
were  on  an  average  shorter  men  ;  while  their  arms  were 
shorter  by  1.09  of  an  inch,  and  therefore,  out  of  proportion, 
shorter  in  relation  to  their  lesser  height.  This  shortness  of 
the  arms  is  apparently  due  to  their  greater  use,  and  is  an 
unexpected  result:  but  sailors  chiefly  use  their  arms  in  pull- 
ing, and  not  in  supporting  weights.  W^ith  sailors,  the  girth 
of  the  neck  and  the  depth  of  the  instep  are  greater,  while 

*Dr.  Brakenridge,  "Theory  of  Diathesis,"  "Medical  Times," 
June  19  and  July  17,  1869. 

f  1  have  given  authorities  for  these  several  statements  in  my 
"Variation  of  Animals  under  Domestication,"  vol.  ii,  pp.  297-300. 
Dr.  Jaeger,  "  Ueber  das  Langenwachsthum  der  Knochen,"  "  Jenais- 
chen  Zeitschrift,"  B.  v,  Heft.  i. 

\  "  Investigations,"  etc.     By  B.  A.  Gould,  1869,  p.  33§. 


MANNER  OF  DEVELOPMENT.  37 

the  cireiimference  of  tlie  chest,  waist,  and  hips  is  less  than 
in  soldiei*s. 

Whether  the  several  foregoing  modifications  would  be- 
come hereditary,  if  the  same  habits  of  life  were  followed 
during  many  generations,  is  not  known,  but  it  is  probable. 
Rengger*  attributes  the  thin  legs  and  thick  arms  of  tlie 
Payaguas  Indians  to  successive  generations  having  passed 
nearly  their  whole  lives  in  canoes,  with  their  lower  extremi- 
ties motionless.  Other  writers  have  come  to  a  similar  con- 
clusion in  analogous  cases.  According  to  Cranz,  f  who  lived 
for  a  long  time  with  the  Esquimaux,  "  the  natives  believe 
that  ingenuity  and  dexterity  in  seal-catching  (their  highest 
art  and  virtue)  is  hereditary;  there  is  really  something  in 
it,  for  the  son  of  a  celebrated  seal-catcher  will  distinguish 
himself,  though  he  lost  his  father  in  childhood.^'  But  in 
this  case  it  is  mental  aptitude,  quite  as  much  as  bodily 
structure,  which  appears  to  be  inherited.  It  is  asserted 
that  the  hands  of  English  laborers  are  at  birth  larger  than 
those  of  the  gentry.  |  From  the  correlation  which  exists, 
at  least  in  some  cases,  §  between  the  development  of  the  ex- 
tremities and  of  the  Jaws,  it  is  possible  that  in  those  classes 
which  do  not  labor  much  with  their  hands  and  feet,  the 
jaws  would  be  reduced  in  size  from  this  cause.  That  they 
are  generally  smaller  in  refined  and  civilized  men  than  in 
hard-working  men  or  savages,  is  certain.  But  with  savages, 
as  Mr.  Herbert  Spencer ||  has  remarked,  the  greater  use  of 
the  jaws  in  chewing  coarse,  uncooked  food,  would  act  in  a 
direct  manner  on  the  masticatory  muscles,  and  on  the  bones 
to  which  they  are  atttiched.  In  infants,  long  before  birth, 
the  skin  on  the  soles  of  the  feet  is  thicker  than  on  any  other 
part  of  the  body;^  and  it  can  hardly  be  doubted  that  this  is 
due  to  the  inherited  effects  of  pressure  during  a  long  series 
of  generations. 

It  is  familiar  to  every  one  that  watchmakers  and  engrav- 
ers are  liable  to  be  short-sighted,  while  men  lining  much 
out  of  doors,   and  especially  savages,  are  generally  long- 

*  "  Saugetliiere  von  Paraguay,"  1830,  s.  4. 

f  "  History  of  Greenland,"  Eng.  translat.,  1767,  vol.  i,  p.  230. 

X  "  Intermarriage."     By  Alex.  Walker,  1838,  p.  377. 

§  "  The  Variation  of  Animals  nnder  Domestication,"  vol.  i,  p.  173. 

I  "  Principles  of  Biology,"  vol.  i,  p.  455. 

^" Paget,  "Lectures  on  Surgical  Pathology,"  vol.  ii,  1853,  p.  209. 


:^A  tHB  DMSCJSNT  OF  MAIT. 

sighted.*  Short-sight  and  long-sight  certainly  tend  to 
bo  inherited.!  The  inferiority  of  Europeans,  in  comparison 
with  savages,  in  eyesight  and  in  the  other  senses,  is  no 
doubt  the  accumulated  and  transmitted  effect  of  lessened 
use  during  many  generations  ;  for  Rengger  |  states  that  he 
has  repeatedly  observed  Europeans,  who  had  been  brought 
up  and  spent  their  whole  lives  with  the  wild  Indians,  who 
nevertheless  did  not  equal  them  in  the  sharpness  of  their 
senses.  The  sanie  naturalist  observes  that  the  cavities  in 
the  skull  for  the  reception  of  the  several  sense-organs  are 
larger  in  the  American  aborigines  than  in  Europeans  ;  and 
this  probably  indicates  a  corresponding  difference  in  the 
dimensions  of  the  organs  themselves.  Blumenbach  has 
also  remarked  on  the  large  size  of  the  nasal  cavities  in  the 
skulls  of  the  American  aborigines,  and  connects  this  fact 
with  their  remarkably  acute  power  of  smell.  The  Mon- 
golians of  the  plains  of  Northern  Asia,  according  to  Pallas, 
have  wonderfully  perfect  senses;  and  Prichard  believes  that 
the  great  breadth  of  their  skulls  across  the  zygomas  follows 
from  their  highly  developed  sense-organs.  § 

The  Quechua  Indians  inhabit  the  lofty  plateaux  of  Peru; 
and  Alcide  d'Orbigny  states  ||  that,  from  continually  breath- 
ing a  highly  rarefied  atmosphere,  they  have  acquired  chests 
and  lungs  of  extraordinary  dimensions.  The  cells,  also,  of 
the  lungs  are  larger  and  more  numerous  than  in  Europeans. 

*  It  is  a  singular  and  unexpected  fact  that  sailors  are  inferior  to 
landsmen  in  their  mean  distance  of  distinct  vision.  Dr.  B.  A.  Gould 
("  Sanitary  Memoirs  of  the  War  of  the  Rebellion,"  1869,  p.  580),  has 
l)n)ved  this  to  be  the  case  ;  and  he  accounts  for  it  by  the  ordinary 
ran^e  of  vision  in  sailors  being  "  restricted  to  the  length  of  the  vessel 
and  the  height  of  the  masts." 

f  '*  The  Variation  of  Animals  under  Domestication,"  vol.  i,  p.  8. 

:}:  "  Siiugethiere  von  Paraguay,"  s.  8,  10.  I  have  had  good  oppor- 
tunities for  observing  the  extraordinary  power  of  eyesight  in  the 
Fuegians.  See  also  Lawrence ("  Lectures  on  Physiology, "etc.,  1822, 
p.  404)  on  this  same  subject.  M.  Giraud-Teulon  has  recently  col- 
lected ("  Revue  des  Cours  Scientifiques,"  1870,  p.  625)  a  large  and 
valuable  body  of  evidence  proving  that  the  cause  of  short-sight, 
*'  C'est  le  travail  assklu,  de  pres." 

^  Prichard,  "  Phys.  Hist,  of  Mankind,"  on  the  authority  of  Blum- 
enbach, vol.  i,  1851,  p.  311  ;  for  the  statement  by  Pallas,  vol.  iv, 
1844,  p.  407. 

II  Quoted  by  Prichard,  "  Researches  into  the  Phys.  Hist,  of  Man- 
kind," vol   v.  p  463. 


MANNER  OF  DEVELOPMENT.  3^ 

These  observations  have  been  doubted  ;  but  Mr.  D.  Forbes 
carefully  measured  many  Aymaras,  an  allied  race,  living  at 
the  height  of  between  10,000  and  15,000  feet ;  and  he  in- 
forms me  *  that  they  differ  conspicuously  from  the  men  of 
all  other  races  seen  by  him  in  the  circumference  and  length 
of  their  bodies.  In  his  table  of  measurements,  the  stature 
of  each  man  is  taken  at  1,000,  and  the  other  measurements 
are  reduced  to  this  standard.  It  is  here  seen  that  the  ex- 
tended arms  of  the  Aymaras  are  shorter  than  those  of 
Europeans,  and  much  shorter  than  those  of  Negroes. 
The  legs  are  likewise  shorter ;  and  they  present  this 
remarkable  peculiarity,  that  in  every  Aymara  me<isured, 
the  femur  is  actually  shorter  than  the  tibia.  On  an 
average,  the  length  of  the  femur  to  that  of  the  tibia  is  as 
211  to  252  ;  while  in  two  Europeans,  measured  at  the  same 
time,  the  femora  to  the  tibiae  were  as  244  to  230 ;  and  in 
three  Negroes  as  258  to  241.  The  humerus  is  likewise 
shorter  relatively  to  the  forearm.  This  shortening  of  that 
part  of  the  limb  which  is  nearest  to  the  body,  ajjpears  to 
be,  as  suggested  to  me  by  Mr.  Forbes,  a  case  of  compensa- 
tion in  relation  with  the  greatly  increased  length  of  the 
trunk.  The  Aymaras  present  some  other  singular  points 
of  structure,  for  instance,  the  very  small  projection  of  the 
heel. 

These  men  are  so  thoroughly  acclimatized  to  their  cold 
and  lofty  abode,  that  when  formerly  carried  down  by  the 
Spaniards  to  the  low  eastern  plains,  and  when  now  tempted 
down  by  the  high  wages  to  the  gold-washings,  they  suffer  a 
frightful  rate  of  mortality.  Nevertheless  Mr.  Forbes  found 
a  few  pure  families  which  had  survived  during  two  genera- 
tions :  and  he  observed  that  tliey  still  inherited  their  char- 
acteristic peculiarities.  But  it  was  manifest,  even  without 
measurement,  that  these  peculiarities  had  all  decreased ; 
and  on  measurement,  their  bodies  were  found  not  to  be  so 
much  elongated  as  those  of  the  men  on  the  high  plateau  ; 
while  their  femora  had  become  somewhat  lengthened,  as 
had  their  tibiae,  although  in  a  less  degree.  The  actual 
measurements  may  be  seen  by  consulting  Mr.  Forbes' 
memoir.  From  these  observations,  there  can,  I  think,  be 
no  doubt  that  residence  during  many  generations  at  a  great 

*Mr.  Forbes'  valuable  paper  is  now  publisLed  in  the  "Journal  of 
the  Ethnological  Soc.  of  London,"  new  series,  vol.  ii,  1870,  p.  193. 


40  THE  DESCENT  OF  MAN, 

elevation  tends,  both  directly  and  indirectly,  to  induce  in- 
herited moditications  in  the  proportions  ot*  the  body.* 

Although  man  may  not  have  been  much  modified  during 
the  latter  stages  of  his  existence  through  the  increased  or 
decreased  use  of  parts,  the  facts  now  given  show  that  his 
liability  in  this  respect  has  not  been  lost ;  and  we  positively 
know  that  the  same  law  holds  good  with  the  lower  animals. 
Consequently  we  may  infer  that  when  at  a  remote  epoch 
tlie  progenitors  of  man  were  in  a  transitional  state,  and 
were  changing  from  quadrupeds  into  bipeds,  natural  selec- 
tion would  probably  have  been  greatly  aided  by  the  in- 
herited effects  of  the  increased  or  diminished  use  of  the  dif- 
ferent parts  of  the  body. 

Arrests  of  Development. — There  is  a  difference  between 
arrested  development  and  arrested  growth,  for  parts  in  the 
former  state  continue  to  grow  while  still  retaining  their 
early  condition.  Various  monstrosities  come  under  this 
head;  and  some,  as  a  cleft-palate,  are  known  to  be  occa- 
sionally inherited.  It  will  suffice  for  our  purpose  to  refer 
to  the  arrested  brain-development  of  microcephalous  idiots, 
as  described  in  Vogt's  memoir,  f  Their  skulls  are  smaller, 
and  the  convolutions  of  the  brain  are  less  complex  than  in 
normal  men.  The  frontal  sinus,  or  the  projection  over  the 
eye-brows,  is  largely  developed,  and  the  jaws  are  pro- 
gnathous to  an  ''  effray an  f  degree;  so  ..that  these  idiots 
somewhat  resemble  the  lower  types  of  mankind.  Their  in- 
telligence, and  most  of  their  mental  faculties,  are  extremely 
feeble.  They  cannot  acquire  the  power  of  speech,  and  are 
wholly  incapable  of  prolonged  attention,  but  are  much 
given  to  imitation.  They  are  strong  and  renuirkably  ac- 
tive, continually  gambolling  and  jumping  about,  and  mak- 
ing grimaces.  They  often  ascend  stairs  on  all-fours;  and 
are  curiously  fond  of  climbing  up  furniture  or  trees.  We 
are  thus  reminded  of  the  delight  shown  by  almost  all  boys 
in  climbing  trees;  and  this  again  reminds  us  how  lambs 
and  kids,  originally  alpine  animals,  delight  to  frisk  on  any 
hillock,   however  small.     Idiots  also   resemble   the   lower 

*Dr.  WilckensC'Landwirthschaft.  Wocbenblatt,"  No.  10,  1869) 
lias  lately  published  an  interesting  Essay  showing  how  domestic  ani- 
mals, which  live  in  mountainous  regions,  have  their  frames  modified. 

f  "Memoire  sur  les  Microcepbales, "  1867,  pp.  50,  125,  169,  171, 
184^198. 


MANNER  OP  DEVELOPMENT.  41 

animals  in  some  other  respects;  thus  several  cases  are  re- 
corded of  their  carefully  smelling  every  mouthful  of  food 
before  eating  it.  One  idiot  is  described  as  often  using  his 
mouth  in  aid  of  his  hands  while  hunting  for  lice.  They 
are  often  filthy  in  their  habits,  and  have  no  sense  of  de- 
cency; and  several  cases  have  been  published  of  their  bodies 
being  remarkably  hairy.* 

Reversion. — Many  of  the  cases  to  be  here  given,  might 
have  been  introduced  under  the  last  heading.  When  a 
structure  is  arrested  in  its  development,  but  still  continues 
growing,  until  it  closely  resembles  a  corresponding  struct- 
ure in  some  lower  and  adult  member  of  the  same  group,  it 
may  in  one  sense  be  considered  as  a  case  of  reversion.  The 
lower  members  in  a  group  give  us  some  idea  how  the  com- 
mon progenitor  was  probably  constructed;  and  it  is  hardly 
credible  that  a  complex  part,  arrested  at  an  early  phase  of 
embryonic  development,  should  go  on  growing  so  as  ulti- 
mately to  perform  its  proper  function,  unless  it  had  ac- 
quired such  power  during  some  earlier  state  of  existence, 
when  the  present  exceptional  or  arrested  structure  was 
normal.  The  simple  brain  of  a  microcephalous  idiot,  in 
as  far  as  it  resembles  that  of  an  ape,  may  in  this  sense  be 
said  to  offer  a  case  of  reversion.!     There  are  other  cases 

*  Prof.  Lavcock  sums  up  the  character  of  brute-like  idiots  by  call- 
ing them  theroid ;  *' Journal  of  Mental  Science,"  July,  1863.  Dr. 
Scott  ("The  Deaf  and  Dumb,"  2d  edit.,  1870,  p.  10)  has  often  ob- 
served the  imbecile  smelling  their  food.  See,  on  this  same  subject, 
and  on  the  hairiness  of  idiots.  Dr.  Maudsley,  "Body  and  Mind," 
1870,  pp.  46-51.  Pinel  has  also  given  a  striking  case  of  hairiness  in 
an  idiot. 

f  In  my  "Variation  of  Animals  under  Domestication"  (vol.  ii,  p. 
57),  I  attributed  the  not  very  rare  cases  of  supernumerary  mammae 
in  women  to  reversion.  I  was  led  to  this  as  a  probable  conclusion, 
by  the  additional  maramse  being  generally  placed  symmetrically  on 
the  breast;  and  more  especially  from  one  case,  in  which  a  single  effi- 
cient mammae  occurred  in  the  inguinal  region  of  a  woman,  the  daugh- 
ter of  another  woman  with  supernumerary  mammae.  But  I  now  find 
(see,  for  instance,  Prof.  Preyer,  '•  Der  Kampf  urn  das  Dasein,"  1869, 
s.  45)  that  mamnup  errnticm  occur  in  other  situations,  as  on  the  back, 
in  the  armpit,  and  on  the  thigh;  the  mammae  in  this  latter  instance 
having  given  so  much  milk  that  the  <;hild  was  thus  nourished.  The 
probability  that  the  additional  mammae  are  due  to  reversion  is  thus 
much  weakened  ;  nevertheless,  it  still  seems  to  me  probable,  because 
two  i)airs  are  <>lten  found  symmetrically  on  the  breast  ;  and  of  this  I 
myself  have  received  information  in  several  cases.     It  is  well  known 


42  THE  DESCENT  OF  MAN, 

which  come  more  strictly  under  our  present  liead  of  rever- 
sion. Certain  structures,  regularly  occurring  in  the  lower 
members  of  the  group  to  which  man  belongs,  occasionally 
make  their  appearance  in  him,  though  not  found  in  the 
normal  human  embryo  ;  or,  if  normally  present  in  the 
human  embryo,  they  become  abnormally  developed,  al- 
though in  a  manner  which  is  normal  in  the  lower  members 
of  the  group.  These  remarks  will  be  rendered  clearer  by 
the  following  illustrations. 

that  some  Lemurs  normally  have  two  pairs  of  mammae  on  the  breast. 
Five  cases  liave  been  recorded  of  the  presence  of  more  than  a  pair  of 
mammae  (of  course  rudimentary)  in  the  male  sex  of  mankind ;  see 
"Journal  of  Anat  and  Physiology,"  1872,  p.  56,  for  a  case  given  by 
Dr.  Handyside,  in  which  two  brothers  exhibited  this  peculiarity  ;  see 
also  a  paper  by  Dr.  Bartels,  in  "  Reichert's  and  du  Bois  Reymond's 
Archiv.,"  1872,  p.  304.  In  one  of  the  cases  alluded  toby  Dr.  Bartels, 
a  man  bore  five  mammae,  one  being  medial  and  placed  above  the 
navel  ;  Meckel  von  Hemsbach  thinks  that  this  latter  case  is  illus- 
trated by  a  medial  mammae  occurring  in  certain  Cheiroptera.  On  the 
whole,  we  may  well  doubt  if  additional  mammae  would  ever  have 
been  developed  in  both  sexes  of  mankind,  had  not  his  early  progeni- 
tors been  provided  with  more  than  a  single  pair.  In  the  above  work 
(vol,  ii,  p.  12),  I  also  attributed,  though  with  much  hesitation,  the 
frequent  cases  of  polydactylism  in  men  and  various  animals  to  rever- 
sion. I  was  partly  led  to  this  through  Prof.  Owen's  statement,  that 
some  of  the  Ichthyopterygia  possess  more  than  five  digits,  and  there- 
fore, as  I  supposed,  had  retained  a  primordial  condition  ;  but  Prof. 
Gegenbaur  ("  Jenaischen  Zeitschrift,"  B.  v,  Heft.  3,  s.  341),  disputes 
Owen's  conclusion.  On  the  other  hand,  according  to  the  opinion 
lately  advanced  by  Dr.  Giinther,  on  the  paddle  of  Ceratodus,  which 
is  provided  with  articulated  bony  rays  on  both  sides  of  a  central 
chain  of  bones,  there  seems  no  great  difficulty  in  admitting  that  six 
or  more  digits  on  one  side,  or  on  both  sides,  might  reappear  through 
reversion.  I  am  informed  by  Dr.  Zouteveen  that  there  is  a  case  on 
record  of  a  man  having  twenty-four  fingers  and  twenty-four  toes  !  I 
was  chiefly  led  to  the  conclusion  that  the  presence  of  supernumerary 
digits  might  be  due  to  reversion  from  the  fact  that  such  digits,  not 
only  are  strongly  inherited,  but,  as  I  then  believed,  had  the  power  of 
regrowth  after  amputation,  like  the  normal  digits  of  the  lower  verte- 
brata.  But  I  have  explained  in  the  second  edition  of  my  Variation 
under  Domestication  why  I  now  place  little  reliance  on  the  recorded 
cases  of  such  regrowth.  Nevertheless  it  deserves  notice,  inasmuch 
as  arrested  development  and  reversion  are  intimately  related  pro- 
cesses ;  that  various  structures  in  an  embryonic  or  arrested  condition, 
such  as  a  cleft  palate,  bifid  uterus,  etc.,  are  frequently  accompanied 
by  polydactylism.  This  has  been  strongly  insisted  on  by  Meckel  and 
Isidore  Ueoffroy  St.-Hilaire.  But  at  present  it  is  the  safest  course  to 
give  up  altogether  the  idea  that  there  is  any  relation  between  the  de- 
velopment of  supernumerary  digits  and  reversion  to  some  lowly  or- 
trani'/ed  progenitor  of  man. 


MANNER  OP  DEVELOPMENT.  4^ 

In  various  mammals  the  uterus  graduates  from  a  double 
organ  with  two  distinct  orifices  and  two  passages,  as  in  the 
marsupials,  into  a  single  organ,  which  is  in  no  way  double 
except  from  having  a  slight  internal  fold,  as  in  the  higher 
apes  and  man.  The  rodents  exhibit  a  perfect  series  of  gra- 
dations between  these  two  extreme  states.  In  all  mammals 
the  uterus  is  developed  from  two  simple  primitive  tubes, 
the  inferior  portions  of  which  form  the  cornua;  and  it  is,  in 
the  words  of  Dr.  Farre,  '^'^by  the  coalescence  of  the  two 
cornua  at  their  lower  extremities  that  the  body  of  the  uterus 
is  formed  in  man;  while  in  those  animals  in  which  no  mid- 
dle portion  or  body  exists,  the  cornua  remain  ununited.  As 
the  development  of  the  uterus  proceeds,  the  two  cornua  be- 
come gradually  shorter,  until  at  length  they  are  lost,  or,  as 
it  were,  absorbed  into  the  body  of  the  uterus.'^  The  angles 
of  the  uterus  are  still  produced  into  cornua,  even  in  ani- 
mals as  high  up  in  the  scale  as  the  lower  apes  and  lemurs. 

Now  in  women,  anomalous  cases  are  not  very  infrequent, 
in  which  the  mature  uterus  is  furnished  with  cornua,  or  is 
partially  divided  into  two  organs;  and  such  cases,  according 
to  Owen,  repeat  *^^  the  grade  of  concentrative  development,"' 
attained  by  certain  rodents.  Here  perhaps  we  have  an  in- 
stance of  a  simple  arrest  of  embryonic  development,  with 
subsequent  growth  and  perfect  functional  development;  for 
either  side  of  the  partially  double  uterus  is  capable  of  per- 
forming the  proper  office  of  gestation.  In  other  and  rarer 
cases,  two  distinct  uterine  cavities  are  formed,  each  having 
its  proper  orifice  and  passage.*  No  such  stage  is  passed 
through  during  the  ordinary  development  of  the  embryo  ; 
and  it  is  difficult  to  believe,  though  perhaps  not  impossible, 
that  the  two  simple,  minute,  primitive  tubes  should  know 
how  (if  such  an  expression  may  be  used)  to  grow  into  two 
distinct  uteri,  each  with  a  well-constructed  orifice  and  pas- 
sage, and  each  furnished  with  numerous  muscles,  nerves, 
glands  and  vessels,  if  they  had  not  formerly  passed  through 
a  similar  course  of  development,  as  in  the  case  of  existing 
marsupials.  No  one  will  pretend  that  so  perfect  a  struct- 
ure as  the  abnormal  double  uterus  in  woman  could  be  the 
result  of  mere  chance.     But  the  principal  of  reversion,  by 

*  See  Dr.  A.  Farre's  well-known  article  in  the  "  Cyclopaedia  of 
Anatomy  and  Physiology,"  vol.  v,  1859,  p.  642.  Owen,  **  Anatomy 
of  Vertebrates,"  vol.  iii,  1868.  p.  687.  Prof.  Turner,  in  "Edinburgh 
Medical  Journal,"  Feb.,  1865. 


44  THE  DESCENT  OF  MAN. 

which  a  long-lost  structure  is  called  back  into  existence, 
might  serve  as  the  guide  for  its  full  development,  even  after 
the  lapse  of  an  enormous  interval  of  time. 

Prof.  Canestrini,  after  discussing  the  foregoing  and 
various  analogous  cases,  arrives  at  the  same  conclusion  as 
that  just  given.  He  adduces  another  instance,  in  the  case 
of  the  malar  bone,*  which,  in  some  of  the  Quadrumana 
and  other  mammals,  normally  consists  of  two  portions. 
This  is  its  condition  in  the  human  foetus  when  two  months 
old  ;  and  through  arrested  development,  it  sometimes 
remains  thus  in  man  when  adult,  more  especially  in  the 
lower  prognathous  races.  Hence  Canestrini  concludes  that 
some  ancient  progenitor  of  man  must  have  had  this  bone 
normally  divided  into  two  portions,  which  afterward  be- 
came fused  together.  In  man  the  frontal  bone  consists  of 
a  single  piece,  but  in  the  embryo,  and  in  children,  and  in 
almost  all  the  lower  mammals,  it  consists  of  two  pieces 
separated  by  a  distinct  suture.  This  suture  occasionally 
persists  more  or  less  distinctly  in  man  after  maturity  ;  and 
more  frequently  in  ancient  than  in  recent  crania,  especially, 
as  Canestrini  has  observed,  in  those  exhumed  from  the 
Drift,  and  belonging  to  the  brachycephalic  type.  Here 
again  he  comes  to  the  same  conclusion  as  in  the  analogous 
case  of  the  malar  bones.  In  this,  and  other  instances 
presently  to  be  given,  the  cause  of  ancient  races  approach- 
ing the  lower  animals  in  certain  characters  more  frequently 
than  do  the  modern  races,  appears  to  be,  that  the  latter 
stand  at  a  somewhat  greater  distance  in  the  long  line  of 
descent  from  their  early  semi-human  progenitors. 

*"Annuario  della  Soc.  dei  Naturalist!  in  Modena,"  1867,  p.  83. 
Prof.  Canestrini  gives  extracts  on  this  subject  from  various  authori- 
ties. Laurillard  remarks,  that  as  lie  has  found  a  complete  similarity 
in  the  form,  proportions,  and  connection  of  the  two  malar  bones  in 
several  human  subjects  and  in  certain  apes,  he  cannot  consider  this 
disposition  of  the  parts  as  simply  accidental.  Another  paper  on  this 
same  anomaly  has  been  published  by  Dr.  Saviotti  in  the  "  Gazzetta 
delle  Cliniche,"  Turin,  1871,  where  he  says  that  traces  of  the  division 
may  be  detected  in  about  two  per  cent,  of  adult  skulls  ;  he  also  re- 
marks that  it  more  frequently  occurs  in  prognathous  skulls,  not  of 
the  Aryan  race,  than  in  others.  See  also  G.  Delorenzi  on  the  same 
subject ;  "  Tre  nuovi  casi  d'anomalia  dell'  osso  malare,"  Torino,  1872. 
Also,  E.  Morselli,  "  Sopra  una  rara  anomalia  dell'  osso  malare," 
Modena,  1872.  Still  more  recently  Gruber  has  written  a  pamphlet 
on  the  division  of  this  bone.  1  give  those  references  because  a  re- 
viewer, without  any  grounds  or  scruples,  has  thrown  doubts  on  my 
statements. 


MANNER  OF  DEVELOPMENT.  45 

Various  other  anomalies  in  man,  more  or  less  analogous 
to  the  foregoing,  have  been  advanced  by  different  authors, 
as  cases  of  reversion  ;  but  these  seem  not  a  little  doubtful, 
for  we  have  to  descend  extremely  low  in  the  mammalian 
series,  before  we  find  such  structures  normally  present.* 

In  man,  the  canine  teeth  are  perfectly  efficient  instruments 
for  mastication.  But  their  true  canine  character,  as  Owenf 
remarks,  "  is  indicated  by  the  conical  form  of  the  crown, 
which  terminates  in  an  obtuse  point,  is  convex  outward 
and  flat  or  sub-concave  within,  at  the  base  of  which  surface 
there  is  a  feeble  prominence.  The  conical  form  is  best  ex- 
pressed in  the  Melanian  races,  especially  the  Australian. 
'^  The  canine  is  more  deeply  implanted,  and  by  a  stronger 
fang  than  the  incisors.'^  Nevertheless,  this  tooth  no  longer 
serves  man  as  a  sj^ecial  weapon  for  tearing  his  enemies  or 
prey  ;  it  may,  therefore,  as  far  as  its  proper  funtion  is  con- 
cerned, be  considered  as  rudimentary.  In  every  large  col- 
lection of  human  skulls  some  may  be  found,  as  HackelJ 
observes,  with  the  canine  teeth  projecting  considerably  be- 
yond the  others  in  the  same  manner  as  in  the  anthropomor- 
phous apes,  but  in  a  less  degree.  In  these  cases,  open 
spaces  between  the  teeth  in  the  one  jaw  are  left  for  the  re- 
ception of  the  canines  of  the  opposite  jaw.  An  interspace 
of  this  kind  in  a  Kaffir  skull,  figured  by  Wagner,  is  sur- 
prisingly wide.§  Considering  how  few  are  the  ancient 
skulls  which  have  been  examined,  compared  to  recent 
skulls,  it  is  an  interesting  fact  that  in  at  least  three  cases 

*  A  whole  series  of  cases  is  given  by  Isid.  Geoffroy  St.-Hilaire, 
"  Hist,  des  Anomalies,"  torn,  iii,  p.  437.  A  reviewer  ("  Journal  of 
Anat.  and  Physiology,"  1871,  p.  366)  blames  me  mucli  for  not  having 
discussed  the  numerous  cases,  which  have  been  recorded,  of  various 
parts  arrested  in  their  development.  He  says  that,  according  to  my 
theory,  "  every  transient  condition  of  an  organ,  during  its  develop- 
ment, is  not  only  a  means  to  an  end,  but  once  was  an  end  in  itself." 
This  does  not  seem  to  me  necessarily  to  hold  good.  Why  should  not 
variation  occur  during  an  early  period  of  development,  having  no 
relation  to  reversion  ;  yet  such  variations  might  be  preserved  and  ac- 
cumulated, if  in  any  way  serviceable,  for  instance,  in  shortening  and 
simplifying  the  course  of  development  ?  And  again,  why  should  not 
injurious  abnormalities,  such  as  atrophied  or  hypertrophied  parts, 
which  have  no  relation  to  a  former  state  of  existence,  occur  at  an 
early  period,  as  well  as  during  maturity  ? 

f  "Anatomy  of  Vert«brat«s,"  vol.  iii,  1868,  p.  323. 

X  "  Generelle  Morphologie,"  1866,  B.  ii,  s.  civ. 

^Carl  Vogt's  "Lectures  on  Man,"  Eng.  translat.,  1864,  p.  151. 


46  THE  DESCENT  OF  MAN. 

the  canines  project  largely  ;  and  in  the  Naulette  jaw  they 
are  spoken  of  as  enormous.* 

Of  the  anthropomorphous  apes  the  males  alone  have  their 
canines  fully  developed  ;  but  in  the  female  gorilla,  and  in 
a  less  degree  in  the  female  orang,  these  teeth  project  con- 
siderably beyond  the  others  ;  therefore  the  fact,  of  which  I 
have  been  assured,  that  women  sometimes  have  considerably 
projecting  canines,  is  no  serious  objection  to  the  belief  that 
their  occasional  great  development  in  man  is  a  case  of  re- 
version to  an  ape-like  progenitor.  He  who  rejects  with 
scorn  the  belief  that  the  shape  of  his  own  canines,  and  their 
occasional  great  development  in  other  men,  are  due  to  our 
early  forefathers  having  been  provided  with  these  formidable 
weapons,  will  probably  reveal,  by  sneering,  the  line  of  his 
descent.  For  though  he  no  longer  intends,  nor  has  the 
power,  to  use  these  teeth  as  weapons,  he  will  unconsciously 
retract  his  "•  snarling  muscles  "  (thus  named  by  Sir  0.  Bell),t 
so  as  to  expose  them  ready  for  action,  like  a  dog  prepared 
to  fight. 

Many  muscles  are  occasionally  developed  in  man,  which 
are  proper  to  the  Quadrumana  or  other  mammals.  Prof. 
Vlacovich];  examined  forty  male  subjects,  and  found  a  mus- 
cle, called  by  him  the  ischio-pubic,  in  nineteen  of  them;  in 
three  others  there  was  a  ligament  which  represented  this 
muscle;  and  in  the  remaining  eighteen  no  trace  of  it.  In 
only  two  out  of  tliirty  female  subjects  was  this  muscle  de- 
veloped on  both  sides,  but  in  three  others  the  rudimentary 
ligament  was  present.  This  muscle,  therefore,  appears  to 
be  much  more  common  in  the  male  than  in  the  female  sex; 
and  on  the  belief  in  the  descent  of  man  from  some  lower 
form,  the  fact  is  intelligible;  for  it  has  been  detected  in 
several  of  the  lower  animals,  and  in  all  of  these  it  serves 
exclusively  to  aid  the  male  in  the  act  of  reproduction. 

Mr.  J.  Wood,  in  his  valuable  series  of  papers,  §  has  mi- 

*C.  Carter  Blake,  on  a  jaw  from  La  Naulette,  "  Anthropolog. 
Review,"  1867,  p.  295.     Schaaffhausen,  ibid.,  1868,  p.  426. 

f  "The  Anatomy  of  Expression,"  1844,  pp.  110,  131. 

I  Quoted  by  Prof.  Canestrini  in  the  "  Annuario,"  etc.,  1867,  p.  90. 

§  These  papers  deserve  careful  study  by  any  one  who  desires  to 
learn  how  frequently  our  muscles  vary,  and  in  varying  come  to  re- 
semble those  of  the  Quadrumana.  The  following  references  relate 
to  the  few  points  touched  on  in  my  text :  "  Proc.  Royal  Soc,"  vol. 
xiv,  1865,  pp.  379-384  ;  vol.  xv,  1866,  pp.  241,  242  ;  vol.  xv,  1867,  p. 
014  ;  vol.  xvi,  1868,  p.  524.     I  may  here  add  that  Dr.  Murie  and  Mr. 


MANNER  OF  DE  VELOPMENT.  47 

nutely  described  a  vast  number  of  inusciilar  variations  in 
man,  which  resemble  normal  structures  in  the  lower  ani- 
mals. The  muscles  which  closely  resemble  those  regularly 
present  in  our  nearest  allies,  the  Quadrumana,  are  too 
numerous  to  be  here  even  specified.  In  a  single  male  sub- 
ject, having  a  strong  bodily  frame,  and  well-formed  skull, 
no  less  than  seven  muscular  variations  were  observed,  all  of 
Avhich  plainly  represented  muscles  proper  to  various  kinds 
of  apes.  This  man,  for  instance,  had  on  both  sides  of  his 
neck  a  true  and  powerful  ''  levator  daviculcB,"  such  as  is 
found  in  all  kinds  of  apes,  and  which  is  said  to  occur  in 
about  one  out  of  sixty  human  subjects.*  Again,  this  man 
had  '^a.  special  abductor  of  the  metatarsal  bone  of  the  fifth 
digit,  such  as  Prof.  Huxley  and  Mr.  Flower  have  shown  to 
exist  uniformly  in  the  higher  and  lower  apes.'^  I  will  give 
only  two  additional  cases;  the  acromio-basilar  muscle  is 
found  in  all  mammals  below  man,  and  seems  to  be  correl- 
ated with  a  quadrupedal  gait,  f  and  it  occurs  in  about  one 
out  of  sixty  human  subjects.  In  the  lower  extremities  Mr. 
BradleyJ;  found  an  abductor  ossis  metatarsi  quinti  in  both 
feet  of  man;  this  muscle  had  not  up  to  that  time  been  re- 
corded in  mankind,  but  is  always  present  in  the  anthropo- 
morphous apes.  The  muscles  of  the  hands  and  arms — parts 
which  are  so  eminently  characteristic  of  man — are  extremely 
liable  to  vary,  so  as  to  resemble  the  corresponding  muscles 
in  the  lower  animals.  §  Such  resemblances  are  either  perfect 
or  imperfect;  yet  in  the  latter  case  they  are  manifestly  of  a 
transitional  nature.  Certain  variations  are  more  common 
in  man,  and  others  in  woman,  without  our  being  able  to 
assign  any  reason.     Mr.  Wood,  after  describing  numerous 

St,  George  Mivart  have  shown  in  their  Memoir  on  the  Lemuroidea 
("Transact.  Zoolog.  Soc,"  vol.  vii,  1869,  p.  96),  how  extraordinarily 
variable  some  of  the  muscles  are  in  these  animals,  and  the  lowest 
members  of  the  Primates.  Gradations,  also,  in  the  muscles  leading 
to  structures  found  in  animals  still  lower  in  the  scale,  are  numerous 
in  the  Lemuroidea. 

*See  also  Prof.  Macalister  in  "Proc.  R.  Irish  Academy,"  vol.  x, 
1868,  p.  124. 

fMr.  Champneys  in  "Journal  of  Anat.  and  Phys.,"  November, 
1871,  p.  178. 

X  "  Journal  of  Anat.  and  Phys.,"  May,  1872,  p.  421. 

§  Prof,  Macalister  (ibid,,  p.  121)  has  tabulated  his  observations, 
and  finds  that  muscular  abnoruialltles  are  most  frequent  in  the  fores- 
arms,  secondly,  in  the  face,  thirdly,  in  the  foot,  etc. 


48  THE  DESCENT  OF  MAN. 

variations,  makes  the  following  pregnant  remark:  "  Notable 
departures  from  the  ordinary  type  of  the  muscular  struct- 
ures run  in  grooves  or  directions,  which  must  be  taken  to 
indicate  some  unknown  factor,  of  much  importance  to  a 
comprehensive  knowledge  of  general  and  scientific  an- 
atomy/'* 

That  this  unknown  factor  is  reversion  to  a  former  state 
of  existence  may  be  admitted  as  in  the  highest  degree 
probable,  t  It  is  quite  incredible  that  a  nuin  should  through 
mere  accident  abnormally  resemble  certain  apes  in  no  less 
than  seven  of  his  muscles,  if  there  had  been  no  genetic  con- 
nection between  them.  On  the  other  hand,  if  man  is  de- 
scended from  some  ape-like  creature,  no  valid  reason  can 
be  assigned  why  certain  muscles  siiould  not  suddenly  reap- 
pear after  an  interval  of  many  thousand  generations,  in  the 
same  manner  as  with  horses,  asses,  and  mules,  dark  col- 
ored stripes  suddenly  reappear  on  the  legs,  and  shoulders, 
after  an  interval  of  hundreds,  or  more  probably  of  thous- 
ands of  generations. 

These  various  cases  of  reversion  are  so  closely  related  to 
those  of  rudimentary  organs  given  in  the  first  chapter,  that 
many  of  them  might  have  been  indifferently  introduced  either 
there  or  here.     Thus  a  human  uterus  furnished  with  cornua 

*The  Rev.  Dr.  Haugliton,  after  giving  ("  Proc.  R.  Irish  Academy," 
June  27,  1864,  p.  715)  a  remarkable  case  of  variation  in  tlie  human 
flexor  poinds  longus,  adds:  "This  remarkable  example  shows  that 
man  may  sometimes  possess  the  arrangement  of  tendons  of  thumb 
and  fingers  characteristic  of  the  macaque  ;  but  whether  such  a  case 
should  be  regarded  as  a  macaque  passing  upward  into  a  man,  or  a 
man  passing  downward  into  a  macaque,  or  as  a  congenital  freak  of 
nature,  I  cannot  undertake  to  say."  It  is  satisfactory  to  hear  so 
capable  an  anatomist,  and  so  embittered  an  opponent  of  evolutionism, 
admitting  even  the  possibility  of  either  of  his  first  propositions. 
Prof.  Macalister  has  also  described  ("  Proc.  R.  Irish  Acad.,"  vol.  x, 
1864,  p.  138)  variations  in  the  flexoi'  pollicis  longus,  remarkable  from 
their  relations  to  the  same  muscle  in  the  Quadrumana. 

\  Since  the  first  edition  of  this  book  appeared,  Mr.  Wood  has  pub- 
lished an(»ther  memoir  in  the  "Phil.  Transactions,"  1870,  p.  83,  on 
the  varieties  of  the  muscles  of  the  human  neck,  shoulder,  and  chest. 
He  here  shows  how  extremely  variable  these  muscles  are,  and  how 
often  and  how  closely  the  variations  resemble  the  normal  muscles  of 
the  lower  animals.  He  sums  up  by  remarking:  "  It  will  be  enough 
for  my  purpose  if  I  have  succeeded  in  showing  the  more  important 
forms  which,  when  occurring  as  varieties  in  the  human  subject,  tend 
to  exhibit  in  a  sufficiently  marked  manner  what  may  be  considered  as 
proofs  and  examples  of  the  Darwinian  principle  of  reversion,  or  law 
of  iuherittuice,  in  this  department  of  anatomical  science." 


MANNER  OF  DEVELOPMENT.  49 

may  be  said  to  represent,  in  a  rudimentary  condition,  the 
same  organ  in  its  normal  state  in  certain  mammals.  Some 
parts  which  are  rudimentary  in  man,  as  the  os  coccyx  in 
both  sexes,  and  the  mamma?  in  the  male  sex,  are  always 
present;  while  others,  such  as  the  supra-condyloid  foramen, 
only  occasionally  appear,  and  therefore  might  have  been  in- 
troduced under  the  head  of  reversion.  These  several  rever- 
sionary structures,  as  well  as  the  strictly  rudimentary  ones, 
reveal  the  descent  of  man  from  some  lower  form  in  an 
unmistakable  manner. 

Correlated  Variation. — In  man,  as  in  the  lower  ani- 
mals, many  structures  are  so  intimately  related,  that  when 
one  part  varies  so  does  another,  without  our  being  able,  in 
most  cases,  to  assign  any  reason.  We  cannot  say  whether 
the  one  part  governs  the  other,  or  whether  both  are  gov- 
erned by  some  earlier  developed  parts.  Various  monstrosi- 
ties, as  I.  Geoffrey  repeatedly  insists,  are  thus  intimately 
connected.  Homologous  structures  are  partially  liable  to 
change  together,  as  we  see  on  the  opposite  sides  of  the  body, 
and  in  the  upper  and  lower  extremities.  Meckel  long  ago 
remarked,  that  when  the  muscles  of  the  arm  depart  from 
their  proper  type,  they  almost  always  imitate  those  of  the 
leg;  and  so,  conversely,  with  the  muscles  of  the  legs.  The 
organs  of  sight  and  hearing,  the  teeth  and  hair,  the  color 
of  the  skin  and  of  the  hair,  color  and  constitution,  are 
more  or  less  correlated.*  Prof.  Schaaffhausen  first  drew 
attention  to  the  relation  apparently  existing  between  a  mus- 
cular frame  and  the  strongly  pronounced  supra-orbital 
ridges,  which  are  so  characteristic  of  the  lower  races  of  man. 

Besides  the  variations  which  can  be  grouped  with  more 
or  less  probability  under  the  foregoing  heads,  there  is  a 
large  class  of  variations  which  may  be  provisionally  called 
spontaneous,  for  to  our  ignorance,  they  appear  to  arise 
without  any  exciting  cause.  It  can,  however,  be  shown 
that  such  variations,  whether  consisting  of  slight  individ- 
ual differences,  or  of  strongly  marked  and  abrupt  devi- 
ations of  structure,  depend  much  more  on  the  constitu- 
tion of  the  organism  than  on  the  nature  of  the  conditions 
to  which  it  has  been  subjected.  \ 

*The  authorities  for  these  several  statements  are  given  in  my 
"Variation  of  Animals  under  Domestication,"  vol.  ii,  pp.  320-335. 

f  This  whole  subject  has  been  discussed  in  chap,  xxiii,  vol.  ii,  of 
my  "  Variation  of  Animals  and  Plants  under  Domestication," 


50  THE  DESCENT  OF  MAN. 

Rate  of  hicrease.  —  Civilized  populations  have  been 
known  nnder  favorable  conditions,  as  in  the  United  States, 
to  double  their  numbers  in  twenty-five  years  ;  and,  accord- 
ing to  a  calculation,  by  Euler,  this  might  occur  in  a  little 
over  twelve  years.*  At  the  former  rate,  the  present  popu- 
lation of  the  United  States  (thirty  millions),  would  in  657 
years  cover  the  whole  terraqueous  globe  so  thickly,  that 
four  men  would  have  to  stand  on  each  square  yard  of  sui-- 
face.  The  primary  or  fundamental  check  to  the  continued 
increase  of  man  is  the  difficulty  of  gaining  subsistence,  and 
of  living  in  comfort.  We  may  infer  that  this  is  the  case 
from  what  we  see,  for  instance,  in  the  United  States, 
where  snbsistence  is  easy,  and  there  is  plenty  of  room.  If 
Buch  means  were  suddenly  doubled  in  Great  Britain,  our 
number  would  be  quickly  doubled.  With  civilized  nations 
this  primary  check  acts  chiefly  by  restraining  marriages. 
The  greater  death-rate  of  infants  in  the  poorest  cUisses  is 
also  very  important;  as  well  as  the  greater  mortality,  from 
various  diseases,  of  the  inhabitants  of  crowded  and  miser- 
able honses  at  all  ages.  The  effects  of  severe  epidemics 
and  wars  are  soon  counterbalanced,  and  more  than  counter- 
balanced in  nations  placed  under  favorable  conditions. 
Emigration  also  comes  in  aid  as  a  temporary  check,  but 
with  the  extremely  poor  classes,  not  to  any  great  extent. 

There  is  reason  to  suspect,  as  Mai  thus  has  remarked,  that 
the  reproductive  power  is  actually  less  in  barbarous, 
than  in  civilized  races.  We  know  nothing  positively 
on  this  head,  for  with  savages  no  census  has  been  taken  ; 
but  from  the  concurrent  testimony  of  missionaries,  and  of 
others  who  have  long  resided  with  such  people,  it  appears 
that  their  families  are  usually  small,  and  large  ones  rare. 
This  may  be  partly  accounted  for,  as  it  is  believed,  by  the 
women  suckling  their  infants  during  a  long  time  ;  but  it 
is  highly  probable  that  savages,  who  often  suffer  much 
hardship,  and  who  do  not  obtain  so  much  nutritious  food 
as  civilized  men,  would  be  actually  less  prolific.  I  have 
shown  in  a  former  work,t  that  all  our  domesticated  quad- 
rupeds and  birds,  and  all  our  cultivated  plants,  are  more 
fertile  than  the  corresponding  species  in  a  state  of  nature. 

*  See  the  ever  memorable  '*  Essav  on  the  Principle  of  Population," 
by  the  Rev.  T.  Malthus,  vol.  i,  182'(8,  pp.  6,  517. 

f  **  Variation  of  Animals  and  Plants  under  Domestication,"  vol.  ii, 
pp.  111-113,  1^3. 


MANNER  OF  DEV  K LOP  MEN  T.  5 1 

It  is  no  valid  objection  to  this  conclusion  that  animals  sud- 
denly supplied  with  an  excess  of  food,  or  when  grown  very 
fat,  and  that  most  plants  on  sudden  removal  from  very 
poor  to  very  rich  soil,  are  rendered  more  or  less  sterile.  We 
might,  therefore,  expect  that  civilized  men,  who  in  one 
sense  are  highly  domesticated,  would  be  more  prolific  than 
wild  men.  It  is  also  probable  that  the  increased  fertility  of 
civilized  nations  would  become,  as  with  our  domestic 
animals,  an  inherited  character  :  it  is  at  least  known  that 
with  mankind  a  tendency  to  produce  twins  runs  in  families.* 
Xotwithstanding  that  savages  appear  to  be  less  prolific 
than  civilized  people,  they  would  no  doubt  rapidly  increase 
if  their  numbers  were  not  by  some  means  rigidly  kept  down. 
The  Santali,  or  hill-tribes  of  India,  have  recently  afforded 
a  good  illustration  of  this  fact ;  for,  as  shown  by  Mr. 
Hunter,  \  they  have  increased  at  an  extraordinary  rate  since 
vaccination  has  been  introduced,  other  pestilences  mitigated, 
and  war  sternly  repressed.  This  increase,  however,  would 
not  have  been  possible  had  not  these  rude  people  spread 
into  the  adjoining  districts,  and  worked  for  hire.  Savages 
almost  always  marry  ;  yet  there  is  some  prudential  restraint, 
for  they  do  not  commonly  marry  at  the  earliest  possible  age. 
The  young  men  are  often  required  to  show  that  they  can 
support  a  wife ;  and  they  generally  have  first  to  earn  the 
price  with  which  to  purchase  her  from  her  parents.  With 
savages  the  difficulty  of  obtaining  subsistence  occasionally 
limits  their  number  in  a  much  more  direct  manner  than 
with  civilized  people,  for  all  tribes  periodically  suffer  from 
severe  famines.  At  such  times  savages  are  forced  to  devour 
much  bad  food,  and  their  health  can  hardly  fail  to  be 
injured.  Many  accounts  have  been  published  of  their  pro- 
truding stomachs  and  emaciated  limbs  after  and  during 
famines.  They  are  then,  also,  compelled  to  wander  much, 
and,  as  I  was  assured  in  Australia,  their  infants  perish  in 
large  numbers.  As  famines  are  periodical,  depending 
chiefly  on  extreme  seasons,  all  tribes  must  fluctuate  in 
number.  They  cannot  steadily  and  regularly  increase,  as 
there  is  no  artificial  increase  in  the  supply  of  food.  Sav- 
ages, when  hard  pressed,  encroach  on  each  other's  terri- 
tories, and  war  is  the  result ;  but  they  are  indeed  almost 

*Mr.  Sedgwick,  "British  and  Foreign  Medico-Chirurg.  Review,** 
July,  1863,  p.  170. 
t  "  The  Annals  of  Rural  Bengal,"  by  W.  W.  Hunter,  1868,  p.  259, 


52  THE  DESCENT  OF  MAN. 

always  at  war  with  their  neighbors.  They  are  liable  to 
many  accidents  on  land  and  water  in  their  search  for  food  ; 
and  in  some  countries  they  suffer  mu(;h  from  the  largei 
beiists  of  prey.  Even  in  India,  districts  have  been  depop- 
ulated by  the  ravages  of  tigers. 

Malthus  has  discussed  these  several  checks,  but  he  does 
not  lay  stress  enough  on  what  is  probably  the  most  import- 
ant of  all,  namely,  infanticide,  especially  of  female  infants, 
and  the  habit  of  procuring  abortion.  These  practices  now 
prevail  in  many  quarters  of  the  world;  and  infanticide  seems 
formerly  to  have  prevailed,  as  Mr.  MMjcnnan*  has  shown, 
on  a  still  more  extensive  scale.  These  practices  appear  to 
have  originated  in  savages  recognizing  the  difficulty,  or 
rather  the  impossibility  of  supporting  all  the  infants  that 
are  born.  Licentiousness  may  also  be  added  to  the  forego- 
ing checks;  but  this  does  not  follow  from  failing  means  of 
subsistance;  though  there  is  reason  to  believe  that  in  some 
cases  (as  in  Japan)  it  has  been  intentionally  encouraged  as 
a  means  of  keeping  down  the  population. 

If  we  look  back  to  an  extremely  remote  epoch,  before 
man  had  arrived  at  the  dignity  of  manhood,  he  would  have 
been  guided  more  by  instinct  and  less  by  reason  than  are 
the  lowest  savages  at  the  present  time.  Our  early  semi- 
human  progenitors  would  not  have  practiced  infanticide  or 
polyandry;  for  the  instincts  of  the  lower  animals  are  never 
so  perverted t  as  to  lead  them  regularly  to  destroy  their  own 
offspring,  or  to  be  quite  devoid  of  jealousy.  There  would 
have  been  no  prudential  restraint  from  marriage,  and  the 
sexes  would  have  freely  united  at  an  early  age.  Hence  the 
progenitors  of  man  would  have  tended  to  increase  rapidly; 

*  "  Primitive  Marriage,"  1865. 

f  A  writer  in  the  "  Spectator"  (March  12,  1871,  p.  320)  comments 
as  follows  on  this  passage:  "Mr.  Darwin  finds  himself  compelled  to 
reintroduce  a  new  doctrine  of  the  fall  of  man.  He  shows  that  the 
instincts  of  the  higher  animals  are  far  nobler  than  the  habits  of  sav- 
age races  of  men,  and  he  finds  himself,  therefore,  compelled  to  re- 
introduce— in  a  form  of  the  substantial  orthodoxy  of  which  he 
appears  to  be  quite  unconscious — and  to  introduce  as  a  scientific 
hypothesis  the  doctrine  that  man's  gain  of  knowledge  Avas  the  cause 
of  a  temporary  but  long-enduring  moral  deterioration,  as  indicated  by 
the  many  foul  customs,  especially  as  to  marriage,  of  savage  tribes. 
What  does  the  Jewish  tradition  of  the  moral  degeneration  of  man 
through  his  snatching  at  a  knowledge  forbidden  him  by  his  highest 
instinct  assert  beyond  this  ?  " 


MANNER  OF  DEVELOPMENT.  53 

but  checks  of  some  kind,  either  periodical  or  constant,  must 
have  kept  down  their  numbers,  even  more  severely  than 
with  existing  savages.  What  the  precise  nature  of  these 
checks  were  we  cannot  say,  any  more  than  with  most  other 
animals.  We  know  that  horses  and  cattle,  which  are  not 
extremely  prolific  animals,  when  first  turned  loose  in  South 
America,  increased  at  an  enormous  rate.  The  elephant, 
the  slowest  breeder  of  all  known  animals,  would  in  a  few 
thousand  years  stock  the  whole  world.  The  increase  of 
every  species  of  monkey  must  be  checked  by  some  means; 
but  not,  as  Brehm  remarks,  by  the  attacks  of  beasts  of 
prey.  No  one  will  assume  that  the  actual  power  of  repro- 
duction in  the  wild  horses  and  cattle  of  America,  was  at 
first  in  any  sensible  degree  increased;  or  that,  as  each  dis- 
trict became  fully  stocked,  this  same  power  was  diminished. 
No  doubt  in  this  case,  and  in  all  others,  many  checks  con- 
cur, and  different  checks  under  different  circumstances; 
periodical  dearths,  depending  on  unfavorable  seasons,  being 
probably  the  most  important  of  all.  So  it  will  have  been 
with  the  early  progenitors  of  man. 

Natural  Selection. — We  have  now  seen  that  man  is  vari- 
able in  body  and  mind;  and  that  the  variations  are  induced, 
either  directly  or  indirectly,  by  the  same  general  causes, 
and  obey  the  same  general  laws,  as  with  the  lower  animals. 
Man  has  spread  widely  over  the  face  of  the  earth,  and  must 
have  been  exposed,  during  his  incessant  migrations,*  to  the 
most  diversified  conditions.  The  inhabitants  of  Tierra  del 
Fuego,  the  Cape  of  Good  Hope,  and  Tasmania  in  the  one 
hemisphere,  and  of  the  Arctic  regions  in  the  other,  must 
have  passed  through  many  climates,  and  changed  their 
habits  many  times,  before  they  reached  their  present  homes,  f 
The  early  progenitors  of  man  must  also  have  tended,  like 
all  other  animals,  to  have  increased  beyond  their  means  of 
subsistence;  they  must,  therefore,  occasionally  have  been 
exposed  to  a  struggle  for  existence,  and  consequently  to  the 
rigid  law  of  natural  selection.  Beneficial  variations  of  all 
kinds  will  thus,  either  occasionally  or  habitually,  have  been 
preserved  and  injurious  ones  eliminated.  I  do  not  refer  to 
strongly  marked  deviations  of  structure,  which  occur  only 

*  See  some  good  remarks  to  this  effect  by  W.  Stanley  Jevons,  "  A 
De<luction  from  Darwin's  Theory,"  "  Nature,"  1869,  p.  231. 
f  Latham,  "Man  and  his  Migrations,"  1851,  p.  135. 


54  'tBE  DESCENT  OF  MAN. 

at  long  intervals  of  time,  but  to  mere  individual  differenced. 
We  know,  for  instance,  that  the  muscles  of  our  hands  and 
feet,  which  determine  our  powers  of  movement,  are  liable, 
like  those  of  the  lower  animals,*  to  incessant  variability. 
If  then  the  progenitors  of  man  inhabiting  any  district,  es- 
pecially one  undergoing  some  change  in  its  conditions,  were 
divided  into  two  equal  bodies,  the  one-half  which  included 
all  the  individuals  best  adapted  by  their  powers  of  move- 
ment for  gaining  subsistence,  or  for  defending  themselves, 
would  on  an  average  survive  in  greater  numbers,  and  pro- 
create more  offspring  than  the  other  and  less  well  endowed 
half. 

Man  in  the  rudest  state  in  which  he  now  exists  is  the 
most  dominant  animal  that  has  ever  appeared  on  this  earth. 
He  has  spread  more  widely  than  any  other  highly  organized 
form:  and  all  others  have  yielded  before  him.  He  mani- 
festly owes  this  immense  superiority  to  his  intellectual  fac- 
ulties, to  his  social  habits,  which  lead  him  to  aid  and  defend 
his  fellows,  and  to  his  corporeal  structure.  The  supreme 
importance  of  these  characters  has  been  proved  by  the  final 
arbitrament  of  the  battle  for  life.  Through  his  powers  of 
intellect,  articulate  language  has  been  evolved;  and  on  this 
his  wonderful  advancement  has  mainly  depended.  As  Mr. 
Chauncey  Wright  remarks:!  ^*^a  psychological  analysis  of 
the  faculty  of  language  shows,  that  even  the  smallest  pro- 
ficiency in  it  might  require  more  brain  power  than  the 
greatest  proficiency  in  any  other  direction."  He  has  in- 
vented and  is  able  to  use  various  weapons,  tools,  traps,  etc., 
with  which  he  defends  himself,  kills  or  catches  prey,  and 
otherwise  obtains  food.  He  has  made  rafts  or  canoes  for 
fishing  or  crossing  over  to  neighboring  fertile  islands.  He 
has  discovered  the  art  of  making  fire,  by  which  hard  and 
stringy  roots  can  be  rendered  digestible,  and  poisonous  roots 
or  herbs  innocuous.  This  discovery  of  fire,  probably  the 
greatest  ever  made  by  man,  excepting  language,  dates  from 
before  the  dawn  of  history.     These  several  inventions,  by 

*  Messrs.  Murie  and  Mivart  in  their  "  Anatomy  of  the  Lemuroidea  " 
("Transact.  Zoolog.  Soc,"  vol.  vii,  1869,  pp.  96-98)  say,  "some 
muscles  are  so  irregular  in  their  distribution  that  they  cannot  be  well 
classed  in  any  of  the  above  groups."  These  muscles  differ  even  on 
the  opposite  sides  of  the  same  individual. 

f  Limits  of  Natural  Selection.  "North  American  Review,"  Oct 
1870,  p.  295. 


MANNER  OF  DEVELOPMENT.  55 

which  man  in  the  rudest  state  has  become  so  pre-eminent, 
are  the  direct  results  of  the  development  of  his  powers  of 
observation,  memory,  curiosity,  imagination,  and  reason.  I 
cannot,  therefore,  understand  how  it  is  that  Mr.  Wallace* 
maintains,  that  "  natural  selection  could  only  have  endowed 
the  savage  with  a  brain  a  little  superior  to  that  of  an  ape." 

Although  the  intellectual  powers  and  social  habits  of 
man  are  of  paramount  importance  to  him,  we  must  not  un- 
derrate the  importance  of  his  bodily  structure,  to  which 
subject  the  remainder  of  this  chapter  will  be  devoted;  the 
development  of  the  intellectual  and  social  or  moral  facul- 
ties being  discussed  in  a  later  chapter. 

Even  to  hammer  with  precision  is  no  easy  matter,  as 
every  one  who  has  tried  to  learn  carpentry  will  admit.  To 
throw  a  stone  with  as  true  an  aim  as  a  Fuegian  in  defend- 
ing himself,  or  in  killing  birds,  requires  the  most  consum- 
mate perfection  in  the  correlated  action  of  the  muscles  of 
the  hand,  arm,  and  shoulder,  and,  further,  a  fine  sense  of 
touch.  In  throwing  a  stone  or  spear,  and  in  many  other 
actions,  a  man  must  stand  firmly  on  his  feet;  and  this  again 
demands  the  perfect  co-adaptation  of  numerous  muscles. 
To  chip  a  flint  into  the  rudest  tool,  or  to  form  a  barbed 
spear  or  hook  from  a  bone,  demands  the  use  of  a  perfect 
hand;  for,  as  a  most  capable  judge,  Mr.  Schoolcraft, f  re- 
marks, the  shaping  fragments  of  stone  into  knives,  lances, 
or  arrow-heads,    shows   '^'^  extraordinary   ability   and   long 

*"  Quarterly  Review,"  April,  1869,  p.  392.  This  subject  is  more 
fully  discussed  in  Mr.  Wallace's  "  Contributions  to  the  Theory  of 
Natural  Selection,"  1870,  in  which  all  the  essays  referred  to  in  this 
work  are  republished.  The  "Essay  on  Man,"  has  been  ably  criti- 
cized by  Prof.  Claparede,  one  of  the  most  distinguished  zoologists  in 
Europe,  in  an  article  published  in  the  "  Bibliotheque  Universelle," 
June.  1870.  The  remark  quoted  in  my  text  will  surprise  every  one 
who  has  read  Mr.  Wallace's  celebrated  paper  on  "  The  Origin  of 
Human  Races  deduced  from  the  Theory  of  Natural  Selection,"  orig- 
inally published  in  the '•  Anthropological  Review,"  May,  1864,  p. 
clviii.  I  cannot  here  resist  quoting  a  most  just  remark  by  Sir  J. 
Lubbock  ("Prehistoric  Times,"  1865,  p.  479)  in  reference  to  this 
paper,  namely,  that  Mr.  Wallace,  "with  characteristic  unselfishness, 
ascribes  it  (i.  e.  the  idea  of  natural  selection)  unreservedly  to  Mr. 
Darwin,  although,  as  is  well  known,  he  struck  out  the  idea  inde- 
pendently, and  published  it,  though  not  with  the  same  elaboration, 
at  the  same  time." 

f  Quoted  by  Mr.  Lawson  Tait  in  his  "  I^aw  of  Natural  Selection," 
"  Dublin  Quarterly  Journal  of  Medical  Science,"  Feb.,  1869.  Dr. 
Keller  is  likewise  quoted  to  the  same  effect. 


56  THE  DESCENT  OF  MAN. 

practice/'  This  is  to  a  great  extent  proved  by  the  fact  that 
primeval  men  practiced  a  division  of  labor  ;  each  man  did 
not  manufacture  his  own  flint  tools  or  rude  pottery,  but 
certain  individuals  appear  to  have  devoted  themselves  to 
such  work,  no  doubt  receiving  in  exchange  the  produce  of 
the  chase.  Archaeologists  are  convinced  that  an  enormous 
interval  of  time  elapsed  before  our  ancestors  thought  of 
grinding  chipped  flints  into  smooth  tools.  One  can  hardly 
doubt,  that  a  man-like  animal  who  possessed  a  hand  and 
arm  sufficiently  perfect  to  throw  a  stone  with  precision,  or 
to  form  a  flint  into  a  rude  tool,  could,  with  sufficient  prac- 
tice, as  far  as  mechanical  skill  alone  is  concerned,  make 
almost  any  thing  which  a  civilized  man  can  make.  The 
structure  of  the  hand  in  this  respect  may  be  compared  with 
that  of  the  vocal  organs,  which  in  the  apes  are  used  for 
uttering  various  signal-cries,  or,  as  in  one  genus,  musical 
cadences;  but  in  man  the  closely  similar  vocal  organs 
have  become  adapted  through  the  inherited  effects  of 
use  for  the  utterance  of  articulate  language. 

Turning  now  to  the  nearest  allies  of  men,  and  therefore 
to  the  best  representatives  of  our  early  progenitors,  we  find 
that  the  hands  of  the  Quadrumana  are  constructed  on  the 
same  general  pattern  as  our  own,  but  are  far  less  perfectly 
adapted  for  diversified  uses.  Their  hands  do  not  serve  for 
locomotion  so  well  as  the  feet  of  a  dog;  as  may  be  seen  in 
such  monkeys  as  the  chimpanzee  and  orang,  which  walk  on 
the  outer  margins  of  the  palms,  or  on  the  knuckles.* 
Their  hands,  however,  are  admirably  adapted  for  climbing 
trees.  Monkeys  seize  thin  branches  or  ropes,  with  the 
thumb  on  one  side  and  the  fingers  and  palm  on  the  other, 
in  the  same  manner  as  we  do.  They  can  thus  also  lift 
rather  large  objects,  such  as  the  neck  of  a  bottle,  to  their 
mouths.  Baboons  turn  over  stones,  and  scratch  up  roots 
with  their  hands.  They  seize  nuts,  insects,  or  other  small 
objects  with  the  thumb  in  opposition  to  the  fingers,  and  no 
doubt  they  thus  extract  eggs  and  the  young  from  the  nests 
of  birds.  American  monkeys  beat  the  wild  oranges  on  the 
branches  until  the  rind  is  cracked,  and  then  tear  it  ofl'  with 
the  fingers  of  the  two  liands.  In  a  wild  state  they  break 
open  hard  fruits  with  stones.  Other  monkeys  open  mussol- 
shells  with  the  two  thumbs.     With  their  fingers  they  pull 

*Owen,  "  Anatomy  of  Vertebrates,"  vol.  iii,  p,  71. 


MANNER  OF  DEVELOPMENT.  57 

out  thorns  and  burrs,  and  hunt  for  each  other^s  parasites. 
They  roll  down  stones,  or  throw  them  at  their  enemies: 
nevertheless,  they  are  clumsy  in  these  various  actions,  and, 
as  I  have  myself  seen,  are  quite  unable  to  throw  a  stone 
with  precision. 

It  seems  to  me  far  from  true  that  because  "  objects  are 
grasped  clumsily  ^^  by  monkeys,  "  ?i  much  less  specialized 
organ  of  prehension  "  would  have  served  them*  equally  well 
with  their  present  hands.  On  the  contrary,  I  see  no  reason 
to  doubt  that  more  perfectly  constnicted  hands  would  have 
been  an  advantage  to  them,  provided  that  they  were  not 
thus  rendered  less  fitted  for  climbing  trees.  We  may  sus- 
pect that  a  hand  as  perfect  as  that  of  man  would  have  been 
disadvantageous  for  climbing;  for  the  most  arboreal  mon- 
keys in  the  world,  namely,  Ateles,  in  America,  Colobus,  in 
Africa,  and  Hylobates,  in  Asia,  are  either  thumbless,  or 
their  toes  partially  cohere,  so  that  their  limbs  are  converted 
into  mere  grasping  hooks,  f 

As  soon  as  some  ancient  member  in  the  great  series  of  the 
Primates  came  to  be  less  arboreal,  owing  to  a  change  in  its 
manner  of  procuring  subsistence,  or  to  some  change  in  the 
surrounding  conditions,  its  habitual  manner  of  progression 
would  have  been  modified;  and  thus  it  would  have  been 
rendered  more  strictly  quadrupedal  or  bipedal.  Baboons 
frequent  hilly  and  rocky  districts,  and  only  from  necessity 
climb  high  trees  ;  %  and  they  have  acquired  almost  the  gait 
of  a  dog.  Man  alone  has  become  a  biped;  and  we  can,  I 
think,  partly  see  how  he  has  come  to  assume  his  erect  atti- 
tude, which  forms  one  of  his  most  conspicuous  characters. 
Man  could  not  have  attained  his  present  dominant  position 
in  the  world  without  the  use  of  his  hands,  which  are  so 
admirably  adapted  to  act  in  obedience  to  his  will.  Sir  C. 
Bell§  insists  that  *^the  hand  supplies  all  instruments,  and 

*"  Quarterly  Review,"  April,  1869,  p.  392. 

f  In  Hylobates  syndactylus,  as  the  name  expresses,  two  of  tlie  toes 
regularly  cohere  ;  and  this,  as  Mr.  Blyth  informs  me,  is  occasionally 
the  case  with  the  toes  of  H.  agilis,  lar,  and  leuciscus.  Colobus  is 
strictly  arboreal  and  extraordinarily  active  (Brehm,  "  Thierleben," 
B.  i,  s.  50),  but  whether  a  better  climber  than  the  species  of  the 
allied  genera,  I  do  not  know.  It  deserves  notice  that  the  feet  of  the 
sloths,  the  most  arboreal  animals  in  the  world,  are  wonderful  hook- 
like. 

I  Brehm,  "Thierleben,"  B.  i,  s.  80. 

§  "  The  Hand,"  etc.     "  Bridge  water  Treatise,"  1833,  p.  38. 


5g  TBJi:  DE8CENT  OF  MAN. 

by  its  correspondence  with  the  intellect  gives  him  universal 
dominion."  But  the  hands  and  arms  could  hardly  have 
become  perfect  enough  to  have  manufactured  weapons,  or 
to  have  hurled  stones  and  spears  with  a  true  aim,  as  long  as 
tliey  were  habitually  used  for  locomotion  and  for  supporting 
the  whole  weight  of  the  body,  or,  as  before  remarked,  so 
long  as  tliey  were  especially  fitted  for  climbing  trees.  Sucli 
rough  treatment  would  also  have  blunted  the  sense  of 
touch,  on  which  their  delicate  use  largely  depends.  From 
these  causes  alone  it  would  have  been  an  advantage  to  man 
to  become  a  biped ;  but  for  many  actions  it  is  indispensable 
that  the  arms  and  whole  upper  part  of  the  body  should  be 
free;  and  he  must  for  this  end  stand  firmly  on  his  feet.  To 
gain  this  great  advantage,  the  feet  have  been  rendered  flat; 
and  the  great  toe  has  been  peculiarly  modified,  though  this 
has  entailed  the  almost  complete  loss  of  its  power  of  pre- 
hension. It  accords  with  the  principle  of  the  division  of 
physiological  labor,  prevailing  throughout  the  animal 
kingdom,  that  as  the  hands  become  perfected  for  prehen- 
sion, the  feet  should  have  become  perfected  for  support 
and  locomotion.  AVith  some  savages,  however,  the  foot 
has  not  altogether  lost  its  prehensile  power,  as  shown  by 
their  manner  of  climbing  trees  and  of  using  them  in  other 
ways.  * 

If  it  be  an  advantage  to  man  to  stand  firmly  on  his  feet 
and  to  have  his  hands  and  arms  free,  of  which,  from  his 
pre-em,inent  success  in  the  battle  of  life,  there  can  be  no 
doubt,  then  I  can  see  no  reason  why  it  should  not  have  been 
advantageous  to  the  progenitors  of  man  to  have  become  more 
and  more  erect  or  bipedal.  They  would  thus  have  been 
better  able  to  defend  themselves  with  stones  or  clubs,  to 
attack  their  prey,  or  otherwise  to  obtain  food.  The  best 
built  individuals  would  in  the  long  run  have  succeeded 
best  and  have  survived  in  larger  numbers.  If  the  gorilla 
and  a  few  allied  forms  had  become  extinct,  it  might  have 
been  argued,  with  great  force  and  apparent  truth,  that  an 

*  Hackel  bas  an  excellent  discussion  on  the  steps  by  wbicb  man 
became  a  biped;  "  Natiirlicbe  Scbopfnng^sg-escbicbte,"  1868,  s.  507. 
Dr.  Biichner  ("  Conferences  sur  la  Tbeorie  Darwinienne,"  1869,  p. 
135)  bas  given  good  cases  of  tbe  use  of  the  foot  as  a  prebensile  organ 
by  man  ;  and  lias  also  written  (m  tbe  manner  of  progression  of  tbe 
higher  apes,  to  wbicb  I  allude  in  tlie  following  paragraph  ;  see  also 
Owen  ("  Anatomy  of  Vertebrates,"  vol.  iii,  p.  71)  on  this  latter 
subject. 


MANNER  OF  DEVELOPMENT.  59 

animal  could  not  have  been  gradually  converted  from  a 
quadruped  into  a  biped,  as  all  the  individuals  in  an  inter- 
mediate condition  would  have  been  miserably  ill-fitted  for 
progression.  But  we  know  (and  this  is  well  worthy  of  re- 
flection) that  the  anthropomorphous  apes  are  now  actually 
in  an  intermediate  condition  ;  and  no  one  doubts  that  they 
are  on  the  whole  well  adapted  for  their  conditions  of  life. 
Thus  the  gorilla  runs  with  a  sidelong  shambling  gait,  but 
more  commonly  progresses  by  resting  on  its  bent  hands. 
The  long-armed  apes  occasionally  use  their  arms  like 
crutches,  swinging  their  bodies  forward  between  them,  and 
some  kinds  of  Hylobates,  without  having  been  taught,  can 
walk  or  run  upright  with  tolerable  quickness ;  yet  they 
move  awkwardly  and  much  less  securely  than  man.  AVe 
see,  in  short,  in  existing  monkeys  a  manner  of  progression 
intermediate  between  that  of  a  quadruped  and  a  biped; 
but,  as  an  unprejudiced  judge*  insists,  the  anthropo- 
morphous apes  approach  in  structure  more  nearly  to  the 
bipedal  than  to  the  quadrupedal  type. 

As  the  progenitors  of  man  became  more  and  more  erect, 
with  their  hands  and  arms  more  and  more  modified  for 
prehension  and  other  purposes,  with  their  feet  and  legs  at 
the  same  time  transformed  for  firm  support  and  progres- 
sion, endless  other  changes  of  structure  would  have  be- 
come necessary.  The  pelvis  would  have  to  be  broadened, 
the  spine  peculiarly  curved,  and  the  head  fixed  m  an 
altered  position,  all  of  which  changes  have  been  attained 
by  man.  Prof.  Schaaffhausenf  maintains  that  *^the  pow- 
erful mastoid  processes  of  the  human  skull  are  the  result 
of  his  erect  position;"  and  these  processes  are  absent  in 
the  orang,  chimpanzee,  etc.,  and  are  smaller  in  the  go- 
rrilla  than  in  man.  Various  other  structures,  which  appear 
connected  with  man's  erect  position,  might  here  have  been 
added.  It  is  very  difficult  to  decide  how  far  these  corre- 
lated modifications  are  the  result  of  natural  selection,  and 
how  far  of  the  inherited  effects  of  the  increased  use  of  cer- 
tain  parts   or    of    the  action   of    one  part    on    another. 

*  Prof.  Broca,  La  Constitution  des  Vertebres  caudales  ;  "  La  Revue 
d'Anthropologie,"  1872.  p.  26  (separate  copy). 

f  "On  the  Primitive  Form  of  the  Skull,"  translated  in  "Anthrop- 
ological Review,"  Oct.  1868,  p.  428.  Owen  ("Anatomy  of  Verte- 
brates," vol.  ii,  1866,  p.  531)  on  the  mastoid  processes  in  the  higher 
apes. 


60  tse  descent  of  man. 

No  doubt  these  means  of  change  often  co-operate;  thus 
when  certain  muscles,  and  tlie  crests  of  bone  to  which 
they  are  attached,  become  enlarged  by  habitual  use,  this 
shows  that  certain  actions  are  habitually  performed  and 
must  be  serviceable.  Hence  the  individuals  which  per- 
formed them  best  would  tend  to  survive  in  greater  numbers. 

The  free  use  of  the  arms  and  hands,  partly  the  cause 
and  partly  the  result  of  man's  erect  position,  appears  to 
have  led  in  an  indirect  manner  to  other  modifications  of 
structure.  The  early  male  forefathers  of  man  were,  as 
previously  stated,  probably  furnished  with  great  canine 
teeth;  but  as  they  gradually  acquired  the  habit  of  using 
stones,  clubs,  or  other  weapons  for  fighting  with  their 
enemies  or  rivals  they  would  use  their  jaws  and  teeth  less 
and  less.  In  this  case  the  jaws,  together  with  the  teeth, 
would  become  reduced  in  size,  as  we  may  feel  almost  sure 
from  innumerable  analogous  cases.  In  a  future  chapter 
we  shall  meet  with  a  closely  parallel  case  in  the  reduction 
or  complete  disappearance  of  the  canine  teeth  in  male 
ruminants,  apparently  in  relation  with  the  development  of 
their  horns;  and  in  horses  in  relation  to  their  habits  of 
fighting  with  their  incisor  teeth  and  hoofs. 

In  the  adult  male  anthropomorphous  apes,  as  Eiiti- 
meyer*  and  others  have  insisted,  it  is  the  effect  on  the 
skull  of  the  great  development  of  the  jaw-muscles  that  causes 
it  to  differ  so  greatly  in  many  respects  from  that  of  man, 
and  has  given  to  these  animals  ^'  a  truly  frightful  physi- 
ognomy." Therefore,  as  the  jaws  and  teeth  in  man's  pro- 
genitors gradually  become  reduced  in  size,  the  adult  skull 
would  have  come  to  resemble  more  and  more  that  of  exist- 
ing man.  As  we  shall  hereafter  see,  a  great  reduction  of 
the  canine  teeth  in  the  males  would  almost  certainly  affect 
the  teeth  of  the  females  through  inheritance. 

As  the  various  mental  faculties  gradually  developed 
themselves  the  brain  would  almost  certainly  become  larger. 
No  one,  I  presume,  doubts  that  the  large  proportion  which 
the  size  of  man's  brain  bears  to  his  body,  compared  to  the 
same  proportion  in  the  gorilla  or  orang,  is  closely  connected 
with  his  higher  mental  powers.  We  meet  with  closely 
analogous  facts  with  insects,  for  in  ants  the  cerebral  gan- 
glia are  of  extraordinary  dimensions,  and  in  all  the  Hyme- 

*"Die  Grenzen  der  Tliierwelt,  eine  Betrachtung  zu  Darwin's 
Lelire,"  1868,  s.  51. 


MANNER  OF  DEVELOPMENT.  61 

noptera  these  ganglia  are  many  times  larger  than  in  the 
less  intelligent  orders,  such  as  beetles.*  On  the  other 
hand,  no  one  supposes  that  the  intellect  of  any  two  ani- 
mals or  of  any  two  men  can  be  accurately  gauged  by  the 
cubic  contents  of  their  skulls.  It  is  certain  that  there 
may  be  extraordinary  mental  activity  with  an  extremely 
small  absolute  mass  of  nervous  matter:  thus  the  wonder- 
fully diversified  instincts,  mental  powers  and  affections  of 
ants  are  notorious,  yet  their  cerebral  ganglia  are  not  so 
large  as  the  quarter  of  a  small  pin^s  head.  Under  this 
point  of  view  the  brain  pf  an  ant  is  one  of  the  most  mar- 
velous atoms  of  matter  in  the  w^orld,  perhaps  more  so  than 
the  brain  of  a  man. 

The  belief  that  there  exists  in  man  some  close  relation 
between  the  size  of  the  brain  and  the  development  of  the 
intellectual  faculties  is  supported  by  the  comparison  of  the 
skulls  of  savage  and  civilized  races,  of  ancient  and  modern 
people,  and  by  the  analogy  of  the  whole  vertebrate  series. 
Dr.  J.  Barnard  Davis  has  proved,!  by  many  careful  meas- 
urements, that  the  mean  internal  capacity  of  the  skull  in 
Europeans  is  92.3  cubic  inches;  in  Americans  87.5;  in 
Asiatics  87.1;  and  in  Australians  only  81.9  cubic  inches. 
Professor  Broca  X  found  that  the  nineteenth  century 
skulls  from  graves  in  Paris  were  larger  than  those  from 
vaults  of  the  twelfth  century,  in  the  proportion  of  1484  to 
1426;  and  that  the  increased  size,  as  ascertained  by  meas- 
urements, was  exclusively  in  the  frontal  part  of  the  skull — 
the  seat  of  the  intellectual  faculties.  Prichard  is  per- 
suaded that  the  present  inhabitants  of  Britain  have 
^^  much  more  capacious  brain-cases  "  than  the  ancient  in- 
habitants. Nevertheless,  it  must  be  admitted  that  some 
skulls  of  very  high  antiquity,  such  as  the  famous  one  of 
Keanderthal,  are  well    developed  and  capacious.  §     AVith 

*Dujardin,  "  Annales  des  Sc.  Nat.,"  3d  series  Zoolog.  torn,  xiv, 
1850,  p.  203.  See  also  Mr.  Lowne,  ' '  Anatomy  and  Phvs.  of  the 
Musca  xomitoria"  1870,  p.  14.  My  son,  Mr.  F,  Darwin,  dissected 
for  me  the  cerebral  ganglia  of  tlie  Formica  rufa. 

t  "  Philosophical  Transactions,"  1869,  p.  513. 

X  "  Les  Selections,"  M.  P.  Broca,  "  Revue  d'Anthropologies,"  1873  ; 
see  also,  as  quoted  in  C.  Vogt's  "  Lectures  on  Man,"  Eng.  translat., 
1864,  pp.  88,  90.  Prichard,  "  Phys.  Hist,  of  Mankind,"  vol.  i,  1838, 
p.  305. 

§  In  the  interesting  article  just  referred  to.  Prof.  Broca  has  well 
remarked,  that  in  civilized  nations,  the  average  capacity  of  the  skull 


62  THE  DESCENT  OF  MAN. 

respect  to  the  lower  animals,  M.  E.  Lartet,*  by  comparing 
the  crania  of  tertiary  and  recent  mammals  belonging  to 
the  same  groups,  has  come  to  the  remarkable  conclusion 
that  the  brain  is  generally  larger  and  the  convolutions  are 
more  complex  in  the  more  recent  forms.  On  the  other 
hand,  I  have  shown  f  that  the  brains  of  domestic  rabbits 
are  considerably  reduced  in  bulk,  in  comparison  with  those 
of  the  wild  rabbit  or  hare;  and  this  may  be  attributed  to 
their  having  been  closely  confined  during  many  genera- 
tions, so  that  they  have  exerted  their  intellect,  instincts, 
senses  and  voluntary  movements  but  little. 

The  gradually  increasing  weight  of  the  brain  and  skull 
in  man  must  have  influenced  the  development  of  the  sup- 
porting spinal  column,  more  especially  while  he  was  becom- 
ing erect.  As  this  change  of  position  was  being  brought 
about,  the  internal  pressure  of  the  brain  will  also  have  in- 
fluenced the  form  of  the  skull;  for  many  facts  show  how 
easily  the  skull  is  thus  affected.  Ethnologists  believe  that 
it  is  modified  by  the  kind  of  cradle  in  which  infants  sleep. 
Habitual  spasms  of  the  muscles,  and  a  cicatrix  from  a  se- 
vere burn,  have  permanently  modified  the  facial  bones.  In 
young  persons  whose  heads  have  become  fixed  either  side- 
ways or  backward,  owing  to  disease,  one  of  the  two  eyes 
has  changed  its  position,  and  the  shape  of  the  skull  has 
been  altered  apparently  by  the  pressure  of  the  brain  in  a 
new  direction.  \     I  have  shown  that  with  long-eared  rabbits 

must  be  lowered  by  the  preservation  of  a  considerable  nnmber  of  in- 
dividuals, weak  in  mind  and  body,  who  would  have  been  promptly 
eliminated  in  the  savage  state.  On  the  other  hand,  with  savages,  the 
average  includes  only  the  more  capable  individuals,  who  have  lieen 
able  to  survive  under  extremely  hard  conditions  of  life.  Broca  thus 
explains  the  otherwise  inexplicable  fact,  that  the  mean  capacity  of 
the  skull  of  the  ancient  Troglodytes  of  Lozere  is  greater  than  that  of 
modern  Frenchmen. 

*  •*  Comptes-rendus  des  Sciences,"  etc.,  June  1,  1868. 

f  "The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  i,  pp.  134-129. 

X  Schaaffhausen  gives  from  Blumenbach  and  Busch,  the  cases  of 
the  spasms  and  cicatrix,  in  "  Anthropolog.  Review,"  Oct.  1868,  p. 
420.  Dr.  Jarrold  ("  Anthropologia,"  1808,  pp.  115,  116)  adduces  from 
Camper  and  from  his  own  observations,  cases  of  the  modification  of 
the  skull  from  the  head  being  fixed  in  an  unnatural  position.  He 
believes  that  in  certain  trades,  such  as  that  of  a  shoemaker,  where 
the  head  is  habitually  held  forward,  the  forehead  becomes  more 
rounded  and  prominent. 


MANNER  OF  DEVELOPMENT.  63 

even  so  trifling  a  cause  as  the  lopping  forward  of  one  ear 
drags  forward  almost  every  bone  of  the  skull  on  that  side; 
so  that  the  bones  on  the  opposite  side  no  longer  strictly 
correspond.  Lastly,  if  any  animal  were  to  increase  or 
diminish  much  in  general  size,  without  any  change  in  its 
mental  powers,  or  if  the  mental  powers  were  to  be  much 
increased  or  diminished,  without  any  great  change  in  the 
size  of  the  body,  the  shape  of  the  skull  would  almost  cer- 
tainly be  altered.  I  infer  this  from  my  observations  on 
domestic  rabbits,  some  kinds  of  which  have  become  ver}^ 
much  larger  than  the  wild  animal,  while  others  have  re- 
tained nearly  the  same  size,  but  in  both  cases  the  brain  has 
been  much  reduced  relatively  to  the  size  of  the  body.  Xow 
I  was  at  first  much  surprised  on  finding  that  in  all  these 
rabbits  the  skull  had  become  elongated  or  dolichocephalic; 
for  instance,  of  two  skulls  of  nearly  equal  breadth,  the  one 
from  a  wild  rabbit  and  the  other  from  a  large  domestic 
kind,  the  former  was  3.15  and  the  latter  4.3  inches  in 
length.*  One  of  the  most  marked  distinctions  in  different 
races  of  men  is  that  the  skull  in  some  is  elongated  and  in 
others  rounded;  and  here  the  explanation  suggested  by  the 
case  of  the  rabbits  may  hold  good;  for  Welcker  finds  that 
short  "  men  incline  more  to  brachycephaly,  and  tall  men 
to  dolichocephaly;"t  and  tall  men  may  be  compared  with 
the  larger  and  longer-bodied  rabbits,  all  of  which  have 
elongated  skulls,  or  are  dolichocephalic. 

From  these  several  facts  we  can  understand,  to  a  certain 
extent,  the  means  by  which  the  great  size  and  more  or  less 
rounded  form  of  the  skull  have  been  acquired  by  man;  and 
these  are  characters  eminently  distinctive  of  him  in  com- 
parison with  the  lower  animals. 

Another  most  conspicuous  difference  between  man  and 
the  lower  animals  is  the  nakedness  of  his  skin.  Whales 
and  porpoises  (Cetacea),  dugongs  (Sirenia)  and  the  hippo- 
potamus are  naked;  and  this  may  be  advantageous  to  them 
for  gliding  through  the  water;  nor  would  it  be  injurious  to 
them  from  the  loss  of  warmth,  as  the  species  which  in- 
habit the  colder  regions  are  protected  by  a  thick  layer  of 
blubber,  serving  the  same  purposes  as  the  fur  of  seals  and 

*"  Variation  of  Animals,"  etc.,  vol.  i,  p.  117,  on  the  elongation  of 
the  skall  ;  p.  119,  on  the  effect  of  the  lopping  of  one  ear. 

f  Quoted  by  SchaaJlhauseu,  in  "  Anthropolog.  Review,"  Oct.,  1868, 
p.  419. 


64  THE  DESCENT  OF  MAN. 

otters.  Elephants  and  rhinoceroses  are  almost  hairless; 
and  as  certain  extinct  species,  which  formerly  lived  under 
an  Arctic  climate,  were  covered  with  long  wool  or  hair,  it 
would  almost  appear  as  if  the  existing  species  of  both 
genera  had  lost  their  hairy  covering  from  exposure  to  heat. 
This  appears  the  more  probable,  as  the  elephants  in  India 
which  live  on  elevated  and  cool  districts  are  more  hairy  * 
than  those  on  the  lowlands.  May  we  then  infer  that  man 
became  divested  of  hair  from  having  aboriginally  inhabited 
some  tropical  land?  That  the  hair  is  chiefly  retained  in 
the  male  sex  on  the  chest  and  face,  and  in  both  sexes  at 
the  junction  of  all  four  limbs  with  the  trunk,  favors  this 
inference — on  the  assumption  that  the  hair  was  lost  before 
man  became  erect;  for  the  parts  which  now  retain  most 
hair  would  then  have  been  most  protected  from  the  heat  of 
the  sun.  The  crown  of  the  head,  however,  offers  a  curious 
exception,  for  at  all  times  it  must  have  been  one  of  the 
most  exposed  parts,  yet  is  thickly  clothed  with  hair.  The 
fact,  however,  that  the  other  members  of  the  order  of 
Primates,  to  which  man  belongs,  although  inhabiting 
various  hot  regions,  are  well  clothed  with  hair,  generally 
thickest  on  the  upper  surface,!  is  opposed  to  the  supposi- 
tion that  man  became  naked  through  the  action  of  the  sun. 
Mr.  Belt  believes  X  that  within  the  tropics  it  is  an  advant- 
age to  man  to  be  destitute  of  hair,  as  he  is  thus  enabled  to 
free  himself  of  the  multitude  of  ticks  (acari)  and  other 
parasites,  with  which  he  is  often  infested,  and  which  some- 
times cause  ulceration.  But  whether  this  evil  is  of  suffi- 
cient magnitude  to  have  led  to  the  denudation  of  his  body 
through  natural  selection,  may  be  doubted,  since  none  of 
the  many  quadrupeds  inhabiting  the  tropics  have,  as  far  as 

*  Owen,  "Anatomy  of  Vertebrates,"  vol.  iii,  p.  619. 

f  Isidore  Geoffroy  St.-Hilaire  remarks  ("  Hist.  Nat.  Generale,"  tom. 
ii,  1859,  pp.  215-217)  on  the  head  of  man  being  covered  with  long 
hair  ;  also  on  the  upper  surfaces  of  monkeys  and  of  other  mammals 
being  more  thickly  clothed  than  the  lower  surfaces.  This  has  like- 
wise been  observed  by  various  authors.  Prof.  P.  Gervais  ("  Hist. 
Nat.  des  Mammiferes,"  tom.  i,  1854,  p.  28),  however,  states  that  in 
the  gorilla  the  hair  is  thinner  on  the  back  where  it  is  partly  rubbed 
off,  than  on  the  lower  surface. 

X  The  "  Naturalist  in  Nicaragua,"  1874,  p.  209.  As  some  confirma- 
tion of  Mr.  Belt's  view,  I  may  quote  the  following  passage  from  Sir 
W.  Denison  ("Varieties  of  Vice-Regal  Life,"  vol.  i,  1870,  p.  440): 
'•  It  is  said  to  be  a  practice  with  the  Australians,  when  the  vermin 
get  troublesome,  to  singe  themselves." 


MANNER  OF  DEVELOPMENT.  65 

I  know,  acquired  any  specialized  means  of  relief.  The 
view  which  seems  to  me  the  most  probable  is  that  man,  or 
rather  primarily  woman,  became  divested  of  hair  for  orna- 
mental purposes,  as  we  shall  see  under  Sexual  Selection; 
and,  according  to  this  belief,  it  is  not  surprising  that  man 
should  differ  so  greatly  in  hairiness  from  all  other  Primates, 
for  characters,  gained  through  sexual  selection,  often  differ 
to  an  extraordinary  degi'ee  in  closely  related  forms. 

According  to  a  popular  impression,  the  absence  of  a  tail 
is  eminently  distinctive  of  man ;  but  as  those  apes  which 
come  nearest  to  him  are  destitute  of  this  organ  its  disap- 
pearance does  not  relate  exclusively  to  man.  The  tail 
often  differs  remarkably  in  length  within  the  same  genus  : 
thus  in  some  species  of  Macacus  it  is  longer  than  the  whole 
body,  and  is  formed  of  twenty-four  vertebrae;  in  others 
it  consists  of  a  scarcely  visible  stump,  containing  only  three 
or  four  vertebrae.  In  some  kinds  of  baboons  there  are 
twenty-five,  while  in  the  mandrill  there  are  ten  very  small 
stunted  caudal  vertebrae,  or,  according  to  Cuvier,*  some- 
times only  five.  The  tail,  whether  it  be  long  or  short, 
almost  always  tapers  toward  the  end  ;  and  this,  I  presume, 
results  from  the  atrophy  of  the  terminal  muscles,  together 
with  their  arteries  and  nerves,  through  disuse,  leading  to 
the  atrophy  of  the  terminal  bones.  But  no  explanation 
can  at  present  be  given  of  the  great  diversity  which  often 
occurs  in  its  length.  Here,  however,  we  are  more  specially 
concerned  with  the  complete  external  disappearance  of  the 
tail.  Prof.  Broca  has  recently  shownf  that  the  tail  in  all 
quadrupeds  consists  of  two  portions,  generally  separated 
abruptly  from  each  other ;  the  basal  portion  consists  of 
vertebrae,  more  or  less  perfectly  channeled  and  furnished 
with  apophyses  like  ordinary  vertebrae;  whereas  those  of 
the  terminal  portion  are  not  channeled,  are  almost  smooth, 
and  scarcely  resemble  true  vertebrae.  A  tail,  though  not 
externally  visible,  is  really  present  in  man  and  the  anthro- 
pomorphous a]3es,  and  is  constructed  on  exactly  the  same 
pattern  in  both.     In  the  terminal  portion  of  the  vertebrae, 

♦Mr.  St.  George  Mivart.  "  Proc.  Zoolog.  Soc.,"  1865,  pp.  562,  583. 
Dr.  J.  E.  Gray,  *•  Cat.  Brit.  Mus.:  Skeletons.".  Owen,  "Anatomy 
of  Vertebrates,"  vol.  ii,  p.  517.  Isidore  GeofEroy  "Hist.  Nat.  Gen." 
torn,  ii,  p.  244. 

f  "  Revne  d' Anthropologic,"  1872  ;  "  La  Constitution  des  Vertebres 
caudales," 


66  THE  DESCENT  OF  MAN. 

constituting  the  os  coccyx,  are  quite  rudimentary _,  being 
much  reduced  in  size  and  number.  In  the  basal  portion, 
the  vertebrae  are  likewise  few,  are  united  firmly  together, 
and  are  arrested  in  development ;  but  they  have  been  ren- 
dered much  broader  and  flatter  than  the  corresponding 
vertebrae  in  the  tails  of  other  animals  ;  they  constitute 
what  Broca  calls  the  accessory  sacral  vertebrae.  These  are 
of  functional  importance  by  supporting  certain  internal 
parts  and  in  other  ways  ;  and  their  modification  is  directly 
connected  with  the  erect  or  semi-erect  attitude  of  man  and 
the  anthropomorphous  apes.  This  conclusion  is  the  more 
trustworthy,  as  Broca  formerly  held  a  different  view,  which 
he  has  now  abandoned.  The  modification,  therefore,  of 
the  basal  caudal  vertebrae  in  man  and  the  higher  apes  may 
have  been  affected,  directly  or  indirectly,  through  natural 
selection. 

But  what  are  we  to  say  about  the  rudimentary  and 
variable  vertebrae  of  the  terminal  portion  of  the  tail,  form- 
ing the  OS  coccyx  ?  A  notion  which  has  often  been,  and  will 
no  doubt  again  be,  ridiculed,  namely,  that  friction  has  had 
something  to  do  with  the  disappearance  of  the  externa] 
portion  of  the  tail,  is  not  so  ridiculous  as  it  at  first  appears. 
Dr.  Anderson*  states  that  the  extremely  short  tail  of  Maca- 
cus  hrunneus  is  formed  of  eleven  vertebrae,  including  the 
imbedded  basal  ones.  The  extremity  is  tendinous  and 
contains  no  vertebrae;  this  is  succeeded  by  five  rudimentary 
ones,  so  minute  that  together  they  are  only  one  line  and  a 
half  in  length,  and  these  are  permanently  bent  to  one  side 
in  the  shape  of  a  hook.  The  free  part  of  the  tail,  only  a 
little  above  an  inch  in  length,  includes  only  four  more 
small  vertebrae.  This  short  tail  is  carried  erect;  but  about 
a  quarter  of  its  total  length  is  doubled  on  to  itself  to  the 
left;  and  this  terminal  part,  which  includes  the  hook-like 
portion,  serves  '^  to  fill  up  the  interspace  between  the  upper 
divergent  portion  of  the  calosities;"  so  that  the  animal  sits 
on  it  and  thus  renders  it  rough  and  callous.  Dr.  Anderson 
thus  sums  up  his  observations  :  '^  These  facts  seem  to  me 
to  have  only  one  explanation;  this  tail,  from  its  short  size, 
is  in  the  monkey^s  way  when  it  sits  down,  and  frequently 
becomes  placed  under  the  animal  while  it  is  in  this  atti- 
tude; and  from  the  circumstance  that  it  does  not  extend 


Proc.  Zoolog.Soc."  1873,  p.  310, 


MANNER  OF  BE  VELOPMENT.  67 

beyond  the  extremity  of  the  ischial  tuberosities,  it  seems  as 
if  the  tail  originally  had  been  bent  round  by  the  will  of  the 
animal,  into  the  interspace  between  the  callosities,  to  es- 
cape being  pressed  between  them  and  the  ground,  and  that 
in  time  the  curvature  became  permanent,  fitting  in  of  itself 
when  the  organ  happens  to  be  sat  upon/^  Under  these 
circumstances  it  is  not  surprising  that  the  surface  of  the 
tail  should  have  been  roughened  and  rendered  callous,  and 
Dr.  Murie,*  who  carefully  observed  this  species  in  the 
Zoological  Gardens,  as  well  as  three  other  closely  allied 
forms  with  slightly  longer  tails,  says  that  when  the  animal 
eits  down  the  tail  '^  is  necessarily  thrust  to  one  side  of  the 
buttocks;  and  Avhether  long  or  short  its  root  is  consequently 
liable  to  be  rubbed  or  chafed/''  As  we  now  have  evidence 
that  mutilations  occasionally  produce  an  inherited  effect,  f 
it  is  not  very  improbable  that  in  short-tailed  monkeys  the 
projecting  part  of  the  tail,  being  functionally  useless, 
should  after  many  generations  have  become  rudimentary 
and  distorted,  from  being  continually  rubbed  and  chafed. 
We  see  the  projecting  part  in  this  condition  in  the  Maca- 
cus  hrunneus,  and  absolutely  aborted  in  the  M.  ecaudatus 
and  in  several  of  the  higher  apes.  Finally,  then,  as  far  as 
we  can  judge,  the  tail  has  disappeared  in  man  and  the 
anthropomorphous  apes,  owing  to  the  terminal  portion 
having  been  injured  by  friction  during  a  long  lapse  of  time; 
the  basal  and  embedded  portion  having  been  reduced  and 
modified  so  as  to  become  suitable  to  the  erect  or  semi-erect 
position. 

I  have  now  endeavored  to  show  that  some  of  the  most 
distinctive  characters  of  man  have  in  all  probability  been 
acquired,  either  directly,  or  more  commonly  indirectly, 
through  natural  selection.  We  should  bear  in  mind  that 
modifications  in  structure  or  constitution  which  do  not 
serve  to  adapt  an  organism  to  its  habits  of  life,  to  the  food 

*"Proc.  Zoolog.  Soc,"  1872,  p.  786. 

f  I  allude  to  Dr.  Brown-Sequard's  observations  on  the  transmitted 
effect  of  an  operation  causing  epilepsy  in  guinea-pigs,  and  likewise 
more  recently  on  the  analogous  effects  of  cutting  the  sympathetic 
nerve  in  the  neck.  I  shall  hereafter  have  occasion  to  refer  to  Mr. 
Salvin's  interesting  case  of  the  apparently  inherited  effects  of  mot- 
mots  biting  off  the  barbs  of  their  own  tail  feathers.  See  also  on  the 
general  subject  "Variation  of  Animals  and  Plants  under  Domesti- 
cation," vol.  ii,  pp.  22-34 


68  THE  DESCENT  OF  MAN. 

which  it  consumes,  or  passively  to  the  surrounding  con- 
ditions, cannot  have  been  thus  acquired.  We  must  not, 
however,  be  too  confident  in  deciding  what  modifications 
are  of  service  to  each  being;  we  should  remember  how  little 
we  know  about  the  use  of  many  parts,  or  what  changes  in 
the  blood  or  tissues  may  serve  to  fit  an  organism  for  a  new 
climate  or  new  kinds  of  food.  Nor  must  we  forget  the 
principle  of  correlation,  by  which,  as  Isidore  Geoffrey  has 
shown  in  the  case  of  man,  many  strange  deviations  of 
structure  are  tied  together.  Independently  of  correlation, 
a  change  in  one  part  often  leads,  through  the  increased  or 
decreased  use  of  other  parts,  to  other  changes  of  a  quite 
unexpected  nature.  It  is  also  well  to  reflect  on  such  facts, 
as  the  wonderful  growth  of  galls  on  plants  caused  by  the 
poison  of  an  insect,  and  on  the  remarkable  changes  of 
color  in  the  plumage  of  parrots  when  fed  on  certain  fishes, 
or  inoculated  with  the  poison  of  toads;  *  for  we  can  thus 
see  that  the  fluids  of  the  system,  if  altered  for  some 
special  purpose,  might  induce  other  changes.  We  should 
especially  bear  in  mind  that  modifications  acquired  and 
continually  used  daring  past  ages  for  some  useful  purpose, 
would  probably  become  firmly  fixed,  and  might  be  long 
inherited. 

Thus  a  large  yet  undefined  extension  may  safely  be  given 
to  the  direct  and  indirect  results  of  natural  selection;  but 
I  now  admit,  after  reading  the  essay  by  Nageli  on  plants, 
and  the  remarks  by  various  authors  with  respect  to  ani- 
mals, more  especially  those  recently  made  by  Prof.  Broca, 
that  in  the  earlier  editions  of  my  "'Origin  of  Species"  I 
perhaps  attributed  too  much  to  the  action  of  natural  selec- 
tion or  the  survival  of  the  fittest.  I  have  altered  the  fifth 
edition  of  the  ''^Origin"  so  as  to  confine  my  remarks  to 
adaptive  changes  of  structure;  but  I  am  convinced,  from 
the  light  gained  during  even  the  last  few  years,  that  very 
many  structures  which  now  appear  to  us  useless,  will  here- 
after be  proved  to  be  useful,  and  will  therefore  come  within 
the  range  of  natural  selection.  Nevertheless,  I  did  not 
formerly  consider  sufficiently  the  existence  of  structures, 
which,  as  far  as  we  can  at  present  judge,  are  neither  bene- 
ficial nor  injurious;  and  this  I  believe  to  be  one  of  the 
greatest  oversights  as  yet  detected  in  my  work.     I  may  be 

*"The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  pp.  380,  383, 


MANNER  OF  DEVELOPMENT.  69 

permitted  to  say,  as  some  excuse,  that  I  had  two  distinct 
objects  in  view;  firstly,  to  show  that  species  had  not  been 
separately  created,  and  secondly,  that  natural  selection  had 
been  the  chief  agent  of  change,  though  largely  aided  by 
the  inherited  effects  of  habit,  and  slightly  by  the  direct 
action  of  the  surrounding  conditions.  I  was  not,  however, 
able  to  annul  the  influence  of  my  former  belief,  then 
almost  universal,  that  each  species  had  been  purposely 
created;  and  this  led  to  my  tacit  assumption  that  every  de- 
tail of  structure,  excepting  nidiments,  was  of  some  special, 
though  unrecognized,  service.  Any  one  with  this  assump- 
tion in  his  mind  would  naturally  extend  too  far  the  action 
of  natural  selection,  either  dunng  past  or  present  times. 
Some  of  those  who  admit  the  principle  of  evolution,  but 
reject  natural  selection,  seem  to  forget,  when  criticising 
my  book,  that  I  had  the  above  two  objects  in  view;  hence, 
if  I  have  erred  in  giving  to  natural  selection  great  power, 
which  I  am  very  far  from  admitting,  or  in  ha^^ng  exagger- 
ated its  power,  which  is  in  itself  probable,  I  have  at  least, 
as  I  hope,  done  good  service  in  aiding  to  overthrow  the 
dogma  of  separate  creations. 

It  is,  as  I  can  now  see,  probable*  that  all  organic 
beings,  including  man,  possess  peculiarities  of  structure, 
which  neither  are  now,  nor  were  formerly  of  any  service  to 
them,  and  which,  therefore,  are  of  no  physiological  im- 
portance. We  know  not  what  produces  the  numberless 
slight  differences  between  the  individuals  of  each  species, 
for  reversion  only  carries  the  problem  a  few  steps  back- 
ward, but  each  peculiarity  must  have  had  its  efficient 
cause.  If  thes^  causes,  whatever  they  may  be,  were  to  act 
more  uniformly  and  energetically  during  a  lengthened 
period  (and  against  this  no  reason  can  be  assigned),  the  re- 
sult would  probably  be  not  a  mere  slight  individual  differ- 
ence, but  a  well-marked  and  constant  modification,  though 
one  of  no  physiological  importance.  Changed  structures, 
which  are  in  no  way  beneficial,  cannot  be  kept  uniform 
through  natural  selection,  though  the  injurious  will  be 
thus  eliminated.  Uniformity  of  character  would,  however, 
naturally  follow  from  the  assumed  uniformity  of  the  excit- 
ing causes,  and  likewise  from  the  free  intercrossing  of 
many  individuals.  During  successive  periods,  the  same 
organism  might  in  this  manner  acquire  successive  modifi- 
cations, which  would  be  transmitted  in  a  nearly  uniform 


70  THE  DESCENT  OF  MAN, 

stiite  as  long  as  the  exciting  causes  remained  the  same  and 
there  was  free  intercrossing.  With  respect  to  the  exciting 
causes  we  can  only^say,  as  when  speaking  of  so-called  spon- 
taneous variations,  that  they  relate  much  more  closely  to 
the  constitution  of  the  varying  organism,  than  to  the 
nature  of  the  conditions  to  which  it  has  been  subjected. 

Conclusion. — In  this  chapter  we  have  seen  that  as  man 
at  the  present  day  is  liable,  like  every  other  animal,  to  mul- 
tiform individual  differences  or  slight  variations,  so  no 
doubt  were  the  early  progenitors  of  man;  the  variations 
being  formerly  induced  by  the  same  general  causes,  and 
governed  by  the  same  general  and  complex  laws  as  at 
present.  As  all  animals  tend  to  multiply  beyond  their 
means  of  subsistence,  so  it  must  have  been  with  the  pro- 
genitors of  man;  and  this  would  inevitably  lead  to  a  strug- 
gle for  existence  and  to  natural  selection.  The  latter  pro- 
cess would  be  greatly  aided  by  the  inherited  effects  of  the 
increased  use  of  parts,  and  these  two  processes  would  in- 
cessantly react  on  each  other.  It  appears,  also,  as  we  shall 
hereafter  see,  that  various  unimportant  characters  have 
been  acquired  by  man  through  sexual  selection.  An  unex- 
plained residuum  of  change  must  be  left  to  the  assumed 
uniform  action  of  those  unknown  agencies,  which  occasion- 
ally induce  strongly  marked  and  abrupt  deviations  of  struc- 
ture in  our  domestic  productions. 

Judging  from  the  habits  of  savages  and  of  the  greater 
number  of  the  Quadrumana,  primeval  men,  and  even 
their  ape-like  progenitors,  probably  lived  in  society. 
AVith  strictly  social  animals,  natural  selection  sometimes 
acts  on  the  individual,  through  the  preservation  of  vari- 
ations which  are  beneficial  to  the  community.  A  com- 
munity which  includes  a  large  number  of  well-endowed 
individuals  increases  in  number,  and  is  victorious  over 
other  less  favored  ones ;  even  although  each  separate 
member  gains  no  advantage  over  the  others  of  the  same 
community.  Associated  insects  have  thus  acquired  many 
remarkable  structures,  which  are  of  little  or  no  service 
to  the  individual,  such  as  the  pollen-collecting  appa- 
ratus, or  the  sting  of  the  worker-bee,  or  the  great  jaws  of 
soldier-ants.  With  the  higher  social  animals,  I  am  not 
aware  that  any  structure  luxs  been  modified  solely  for  the 
good  of   the  community,  though  some   are   of   secondary 


MANNER  OF  DEVELOPMENT.  71 

service  to  it.  For  instance,  the  horns  of  ruminants  and 
the  great  canine  teeth  of  baboons  appear  to  have  been  ac- 
quired by  the  males  as  weapons  for  sexual  strife,  but  they 
are  used  in  defense  of  the  herd  or  troop.  In  regard  to  cer- 
tain mental  powers  the  case,  as  we  shall  see  in  the  fifth 
chapter,  is  wholly  different;  for  these  faculties  have  been 
chiefly,  or  even  exclusively,  gained  for  the  benefit  of  the 
community,  and  the  individuals  thereof  have  at  the  same 
time  gained  an  advantage  indirectly. 

It  has  often  been  objected  to  such  views  as  the  forego- 
ing, that  man  is  one  of  the  most  helpless  and  defenseless 
creatures  in  the  world;  and  that  during  his  early  and  less 
well  developed  condition  he  would  have  been  still  more 
helpless.  The  Duke  of  Argyll,  for  instance,  insists*  that 
**  the  human  frame  has  diverged  from  the  structure  of 
brutes  in  the  direction  of  greater  physical  helplessness  and 
weakness.  That  is  to  say,  it  is  a  divergence  which  of  all 
others  it  is  most  impossible  to  ascrible  to  mere  natural 
selection."  He  adduces  the  naked  and  unprotected  state 
of  the  body,  the  absence  of  gi*eat  teeth  or  claws  for  de- 
fense, the  small  strength  and  speed  of  man,  and  his  slight 
power  of  discovering  food  or  of  avoiding  danger  by  smell. 
To  these  deficiencies  there  might  be  added  one  still  more 
serious,  namely,  that  he  cannot  climb  quickly  and  so 
escape  from  enemies.  The  loss  of  hair  would  not  have 
been  a  great  injury  to  the  inhabitants  of  a  warm  country. 
For  we  know  that  the  unclothed  Fuegians  can  exist  under 
a  wretched  climate.  When  we  compare  the  defenseless 
state  of  man  with  that  of  apes  we  must  remember  that  the 
great  canine  teeth  with  which  the  latter  are  provided  are 
possessed  in  their  full  development  by  the  males  alone,  and 
are  chiefly  used  by  them  for  fighting  with  their  rivals; 
yet  the  females,  which  are  not  thus  provided,  manage  to 
survive. 

In  regard  to  bodily  size  or  strength,  we  do  not  know 
whether  man  is  descended  from  some  small  species,  like 
the  chimpanzee,  or  from  one  as  powerful  as  the  gorrilla; 
and,  therefore,  we  cannot  say  whether  man  has  become 
larger  and  stronger,  or  smaller  and  weaker  than  his  ances- 
tore.     We  should,  however,  bear  in  mind  that  an  animal 

*  ♦'  Primeval  Man,"  1669,  p.  66. 


72  THE  lyESOENT  OF  MAN. 

possessing  great  size,  strength,  and  ferocity,  and  wliich, 
like  the  gorrilla,  could  defend  itself  from  all  enemies,  would 
not  perhaps  have  become  social:  and  this  would  most  effect- 
ually have  checked  the  acquirement  of  the  higher  mental 
qualities,  such  as  sympathy  and  the  love  of  his  fellows. 
Hence  it  might  have  been  an  immense  advantage  to  man  to 
have  sprung  from  some  comparatively  weak  creature. 

The  small  strength  and  speed  of  man,  his  want  of  nat- 
ural weapons,  etc.,  are  more  than  counterbalanced,  firstly, 
by  his  intellectual  powers,  through  which  he  has  formed 
for  himself  weapons,  tools,  etc.,  though  still  remaining  in 
a  barbarous  state,  and  secondly,  by  his  social  qualities  which 
lead  him  to  give  and  receive  aid  from  his  fellow-men.  No 
country  in  the  world  abounds  in  a  greater  degree  with  dan- 
gerous beasts  than  Southern  Africa;  no  country  presents 
more  fearful  physical  hardships  than  the  Arctic  regions; 
yet  one  of  the  puniest  of  races,  that  of  the  Bushmen,  main- 
tains itself  in  Southern  Africa,  as  do  the  dwarfed  Esqui- 
maux in  the  Arctic  regions.  The  ancestors  of  man  w^ere, 
no  doubt,  inferior  in  intellect,  and  probably  in  social  dis- 
position to  the  lowest  existing  savages;  but  it  is  quite  Con- 
ceivable that  they  might  have  existed,  or  even  flourished, 
if  they  had  advanced  in  intellect,  while  gradually  losing 
their  brute-like  powers,  such  as  that  of  climbing  trees,  etc. 
But  these  ancestors  would  not  have  been  exposed  to  any 
special  danger,  even  if  far  more  helpless  and  defenseless 
than  any  existing  savages,  had  they  inhabited  some  warm 
continent  or  large  island,  such  as  Australia,  New  Guinea, 
or  Borneo,  which  is  now  the  home  of  the  orang.  And 
natural  selection  arising  from  the  competition  of  tribe  with 
tribe  in  some  such  large  area  as  one  of  these,  together  with 
the  inherited  effects  of  habit,  would,  under  favorable  con- 
ditions, have  sufficed  to  raise  man  to  his  present  high 
position  in  the  organic  scale. 


MENTAL  POWERS,  73 


CHAPTER  III. 

COMPARISOiH    OF  THE    MEXTAL   POWERS   OF  MAN"  AJ^D  THE 
LOWER   ANIMALS. 

The  difference  in  mental  power  between  the  highest  ape  and  the 
lowest  savage,  immense  —  Certain  instincts  in  common  —  The 
emotions  —  Curiosity  —  Imitation  —  Attention  — Memory — Imagi- 
nation— Reason — Progressive  improvement — Tools  and  weapons 
used  by  animals — Abstraction,  self -consciousness— Language — 
Sense  of  beauty — Belief  in  God,  spiritual  agencies,  superstitions. 

We  have  seen  in  the  last  two  chapters  that  man  bears 
in  his  bodily  structure  clear  traces  of  his  descent  from 
some  lower  form;  but  it  maybe  urged  that,  as  man  differs 
so  greatly  in  his  mental  power  from  all  other  animals, 
there  must  be  some  error  in  this  conclusion.  Xo  doubt  the 
difference  in  this  respect  is  enormous,  even  if  we  compare 
the  mind  of  one  of  the  lowest  savages,  who  has  no  words 
.to  express  any  number  higher  than  four,  and  who  uses 
hardly  any  abstract  terms  for  common  objects  or  for  the 
affections,*  with  that  of  the  most  highly  organized  ape. 
The  difference  would,  no  doubt,  still  remain  immense,  even 
if  one  of  the  higher  apes  had  been  improved  or  civilized  as 
much  as  a  dog  has  been  in  comparison  with  its  parent-form, 
the  wolf  or  jackal.  The  Fuegians  rank  among  the  lowest 
barbarians  ;  but  I  was  continually  struck  with  surj)rise  how 
closely  the  three  natives  on  board  H.M.S.  *' Beagle,"  who 
had  lived  some  years  in  England,  and  could  talk  a  little 
English,  resembled  us  in  disposition  and  in  most  of  our 
mental  faculties.  If  no  organic  being  excepting  man  had 
possessed  any  mental  power,  or  if  his  powers  had  been  of  a 
wholly  different  nature  from  those  of  the  lower  animals, 
then  we  should  never  have  been  able  to  convince  ourselves 
that  our  high  faculties  had  been  gradually  developed.    But 

*  Seethe  evidence  on  those  points,  as  given  by  Lubbock,  "  Prehis- 
toric Times,"  p.  354,  etc. 


74  THE  DESCENT  OF  MAN. 

it  can  be  shown  that  there  is  no  fundamental  difference  of 
this  kind.  We  must  also  admit  that  there  is  a  much  wider 
interval  in  mental  power  between  one  of  the  lowest  fishes, 
as  a  lamprey  or  lancelet,  and  one  of  the  higher  apes,  than 
between  an  ape  and  man;  yet  this  interval  is  filled  up  by 
numberless  gradations. 

Nor  is  the  difference  slight  in  moral  disposition  between 
a  barbarian,  such  as  the  man  described  by  the  old  navi- 
gator Byron,  who  dashed  his  child  on  the  rocks  for  drop- 
ping a  basket  of  sea-urchins,  and  a  Howard  or  Clarkson; 
and  in  intellect,  between  a  savage  who  uses  hardly  any  ab- 
stract terms,  and  a  Newton  or  Shakespeare.  Differences 
of  this  kind  between  the  highest  men  of  the  highest  races 
and  the  lowest  savages  are  connected  by  the  finest  grada- 
tions. Therefore  it  is  possible  that  they  might  pass  and  be 
developed  into  each  other. 

My  object  in  this  chapter  is  to  show  that  there  is  no  fun- 
damental difference  between  man  and  the  higher  mammals 
in  their  mental  faculties.  Each  division  of  the  subject 
might  have  been  extended  into  a  separate  essay,  but  must 
here  be  treated  briefly.  As  no  classification  of  the  mental 
powers  has  been  universally  accepted,  I  shall  arrange  my 
remarks  in  the  order  most  convenient  for  my  purpose;  and 
will  select  those  facts  which  have  struck  me  most,  with  the 
hope  that  they  may  produce  some  effect  on  the  reader. 

With  respect  to  animals  very  low  in  the  scale,  I  shall  give 
some  additional  facts  under  Sexual  Selection,  showing  that 
their  mental  powers  are  much  higher  than  might  have  been 
expected.  The  variability  of  the  faculties  in  the  individ- 
uals of  the  same  species  is  an  important  point  for  us,  and 
some  few  illustrations  will  here  be  given.  But  it  would  be 
superfluous  to  enter  into  many  details  on  this  head,  for  I 
have  found  on  frequent  inquiry  that  it  is  the  unanimous 
opinion  of  all  those  who  have  long  attended  to  animals  of 
many  kinds,  including  birds,  that  the  individuals  differ 
greatly  in  every  mental  characteristic.  In  what  manner 
the  mental  powers  were  first  developed  in  the  lowest  organ- 
isms, is  as  hopeless  an  inquiry  as  how  life  itself  first  origi- 
nated. These  are  problems  for  the  distant  future  if  they  are 
ever  to  be  solved  by  man. 

As  man  possesses  the  same  senses  as  the  lower  animals, 
his  fundamental  intuitions  must  be  the  same.  Man  has 
also  some  few  instincts  in  common,  as  that  of  self-preserva- 


MENTAL  POWERS.  75 

jtion,  sexual  love,  the  love  of  the  mother  for  her  new-born 
lolTspring,  the  desire  possessed  by  the  latter  to  suck,  and  so 
forth.  But  man,  perhaps,  has  somewhat  fewer  instincts 
than  those  possessed  by  the  animals  which  come  next  to 
him  in  the  series.  The  orang  in  the  Eastern  islands  and 
the  chimpanzee  in  Africa  build  platforms  on  which  they 
sleep;  and  as  both  species  follow  the  same  habit,  it  might 
be  argued  that  this  was  due  to  instinct,  but  we  cannot  feel 
sure  that  it  is  not  the  result  of  both  animals  having  similar 
wants  and  possessing  similar  powers  of  reasoning.  These 
apes,  as  we  may  assume,  avoid  the  many  poisonous  fruits  of 
the  tropics,  and  man  has  no  such  knowledge;  but  as  our 
domestic  animals,  when  taken  to  foreign  lands,  and  when 
first  turned  out  in  the  spring,  often  eat  poisonous  herbs, 
which  they  afterward  avoid,  we  cannot  feel  sure  that  the 
apes  do  not  learn  from  their  own  experience  or  from  that  of 
their  parents  what  fruits  to  select.  It  is,  however,  certain, 
as  we  shall  presently  see,  that  apes  have  an  instinctive  dread 
of  serpents,  and  probably  of  other  dangerous  animals. 

The  fewness  and  the  comparative  simplicity  of  the  in- 
stincts in  the  higher  animals  are  remarkable  in  contrast 
with  the  those  of  the  lower  animals.  Ouvier  maintained 
that  instinct  and  intelligence  stand  in  an  inverse  ratio  to 
each  other ;  and  some  have  thought  that  the  intellectual 
faculties  of  the  higher  animals  have  been  gradually  de- 
veloped from  their  instincts.  But  Pouchet,  in  an  interest- 
ing essay,*  has  shown  that  no  such  inverse  ratio  really 
exists.  Those  insects  which  possess  the  most  wonderful 
instincts  are  certainly  the  most  intelligent.  In  the  ver- 
tebrate series,  the  least  intelligent  members,  namely  fishes 
and  amphibians,  do  not  possess  complex  instincts  ;  and 
among  mammals  the  animal  most  remarkable  for  its  instincts, 
namely  the  beaver,  is  highly  intelligent,  as  will  be  admitted 
by  every  one  who  has  read  Mr.  Morgan's  excellent  work.  \ 
Although  the  first  dawnings  of  intelligence,  according  to 
Mr.  Herbert  Spencer,  J;  have  been  developed  through  the 
multiplication  and  co-ordination  of  reflex  actions,  and 
although  many  of  the  simpler  instincts  graduate  into  reflex 

*  '•  L'Instinct  cbez  les  Insectes,"  "Revue  des  Deux  Mondes,"  Feb. 
1870,  p.  690. 

f  "  The  American  Beaver  and  His  Works,"  1868. 

X ''  The  Principles  of  Psychology,"  2d  edit.,  1870,  pp.  418-443. 


76  THE  DESCENT  OF  MAN. 

actions,  and  can  hardly  be  distinguished  from  them,  as  in 
the  case  of  young  animals  sucking,  yet  the  more  complex 
instincts  seem  to  have  originated  independently  of  intelli- 
gence. I  am,  however,  very  far  from  wishing  to  deny  that 
instinctive  actions  may  lose  their  fixed  and  untaught  char- 
acter and  be  replaced  by  others  performed  by  the  aid  of  the 
free  will.  On  the  other  hand,  some  intelligent  actions, 
after  being  performed  during  several  generations,  become 
converted  into  instincts  and  are  inherited,  as  when  birds 
on  oceanic  islands  learn  to  avoid  man.  These  actions  may 
then  be  said  to  be  degraded  in  character,  for  they  are  no 
longer  performed  through  reason  or  from  experience.  But 
the  greater  number  of  the  more  complex  instincts  appear 
to  have  been  gained  in  a  wholly  different  manner,  through 
the  natural  selection  of  variations  of  simpler  instinctive 
actions.  Such  variations  appear  to  arise  from  the  same 
unknown  causes  acting  on  the  cerebral  organization,  which 
induce  slight  variations  or  individul  differences  in  other 
parts  of  the  body  ;  and  these  variations,  owing  to  our 
ignorance,  are  often  said  to  arise  spontaneously.  We  can, 
I  think,  come  to  no  other  conclusion  with  respect  to  the 
origin  of  the  more  complex  instincts,  when  we  reflect  on 
the  marvelous  instincts  of  sterile  worker-ants  and  bees, 
which  leave  no  offspring  to  inherit  the  effects  of  experience 
and  of  modified  habits. 

Although,  as  we  learn  from  the  above-mentioned  insects 
and  the  beaver,  a  high  degree  of  intelligence  is  certainly 
compatible  with  complex  instincts,  and  although  actions, 
at  first  learned  voluntarily,  can  soon  through  habit  be 
performed  with  the  quickness  and  certainty  of  a  reflex 
action,  yet  it  is  not  improbable  that  there  is  a  certain 
amount  of  interference  between  the  development  of  free 
intelligence  and  of  instinct,  which  latter  implies  some  in- 
herited modification  of  the  brain.  Little  is  known  about 
the  functions  of  the  brain,  but  we  can  perceive  that  as  the 
intellectual  powers  become  highly  developed  the  various 
parts  of  the  brain  must  be  connected  by  very  intricate 
channels  of  the  freest  intercommunication;  and  as  a  conse- 
quence each  separate  part  would  perhaps  tend  to  be  less 
well  fitted  to  answer  to  particular  sensations  or  associations 
in  a  definite  and  inherited — that  is  instinctive — manner. 
Tliere  seems  even  to  exist  some  relation  between  a  low  de- 
gree of  intelligence  and  a  strong  tendency  to  the  formation 


MENTAL  POWERS.  77 

of  fixed,  though  not  inherited  habits;  for  as  a  sagacious 
physician  remarked  to  me,  persons  who  are  slightly  imbecile 
tend  to  act  in  ftvftrythiiig  by  routine  or  habit;  and  they  are 
rendered  much  happier  if  this  is  encouraged. 

I  have  thought  this  digression  worth  giving,  because  we 
may  easily  underrate  the  mental  powers  of  the  higher  ani- 
mals, and  especially  of  man,  when  we  compare  their  actions 
founded  on  the  memory  of  past  events,  on  foresight,  reason 
and  imagination,  with  exactly  similar  actions  instinctively 
performed  by  the  lower  animals;  in  this  latter  case  the 
capacity  of  performing  such  actions  has  been  gained,  step 
by  step,  through  the  variability  of  the  mental  organs  and 
natural  selection,  without  any  conscious  intelligence  on  the 
part  of  the  animal  during  each  successive  generation.  No 
doubt,  as  Mr.  AVallace  has  argued,*  much  of  the  intelligent 
work  done  by  man  is  due  to  imitation  and  not  to  reason; 
but  there  is  this  great  difference  between  his  actions  and 
many  of  those  performed  by  the  lower  animals,  namely, 
that  man  cannot,  on  his  first  trial,  make,  for  instance,  a 
stone  hatchet  or  a  canoe,  through  his  power  of  imitation. 
He  has  to  learn  his  work  by  practice;  a  beaver,  on  the  other 
hand,  can  make  its  dam  or  canal,  and  a  bird  its  nest,  as 
well,  or  nearly  as  well,  and  a  spider  its  wonderful  web, 
quite  as  well,f  the  first  time  it  tries  as  when  old  and 
experienced. 

To  return  to  our  immediate  subject:  the  lower  animals, 
like  man,  manifestly  feel  pleasure  and  pain,  happiness  and 
misery.  Happiness  is  never  better  exhibited  than  by 
young  animals,  such  as  puppies,  kittens,  lambs,  etc. ,  when 
plaWng  together,  like  our  own  children.  Even  insects 
play  together,  as  has  been  described  by  that  excellent 
observer,  P.  Huber,|  who  saw  ants  chasing  and  pretending 
to  bite  each  other,  like  so  many  puppies. 

The  fact  that  the  lower  animals  are  excited  by  the  same 
emotions  as  ourselves  is  so  well  established  that  it  will 
not  be  necessary  to  weary  the  reader  by  many  details. 
Terror  acts  in  the  same  manner  on  them  as  on  us,  causing 
the    muscles    to    tremble,   the    heart    to    palpitate,   the 

*  "  Contributions  to  the  Theory  of  Natural  Selection,"  1870,  p.  212. 

f  For  the  evidence  on  this  head,  see  Mr.  J.  Traheme  Moggridge's 
most  interesting  work,  "  Harvesting  Ants  and  Trap-door  Spiders, ' 
1873,  pp.  126,  128. 

X  "  Recherches  sur  les  Moeurs  des  Fourmis,"  1810,  p.  173. 


78  THE  DESCENT  OF  MAN, 

sphincters  to  be  reltixed,  and  the  hair  to  stand  on  end. 
Suspicion,  the  offspring  of  fear,  is  eminently  characteristic 
of  most  wild  animals.  It  is,  I  think,  impossible  to  read  the 
account  given  by  Sir  E.  Tennent,  of  the  behavior  of  the 
female  elephants,  used  as  decoys,  without  admitting  that 
they  intentionally  practice  deceit,  and  well  know  what  they 
are  about.  Courage  and  timidity  are  extremely  variable 
qualities  in  the  individuals  of  the  same  species,  as  is  plainly 
seen  in  our  dogs.  Some  dogs  and  horses  are  ill-tempered 
and  easily  turn  sulky;  others  are  good-tempered;  and  these 
qualities  are  certainly  inherited.  Every  one  knows  how 
liable  animals  are  to  furious  rage  and  how  plainly  they 
show  it.  Many,  and  probably  true,  anecdotes  have  been 
published  on  the  long-delayed  and  artful  revenge  of  various 
animals.  The  accurate  Kengger  and  Brehm*  state  that 
the  American  and  African  monkeys  which  they  kept  tame 
certainly  revenged  themselves.  Sir  Andrew  Smith,  a  zoolo- 
gist whose  scrupulous  accuracy  was  known  to  many  persons, 
told  me  the  following  story  of  which  he  was  himself  an  eye- 
witness: At  the  Cape  of  Good  Hope  an  officer  had  often 
plagued  a  certain  baboon,  and  the  animal,  seeing  him  ap- 
proaching one  Sunday  for  parade,  poured  water  into  a  hole 
and  hastily  made  some  thick  mud,  which  he  skillfully 
dashed  over  the  officer  as  he  passed  by,  to  the  amusement 
of  many  bystanders.  For  long  afterward  the  baboon  re- 
joiced and  triumphed  whenever  he  saw  his  victim. 

The  love  of  a  clog  for  his  master  is  notorious  ;  as  an  old 
writer  quaintly  says:  f  '^A  dog  is  the  only  thing  on  this 
earth  that  luvs  you  more  than  he  luvs  himself.''^ 

In  the  agony  of  death  a  dog  has  been  known  to  caress  his 
master,  and  every  one  has  heard  of  the  dog  suifering  under 
vivisection,  who  licked  the  hand  of  the  operator;  this  man, 
unless  the  operation  was  fully  justified  by  an  increase  of  our 
knowledge,  or  unless  he  had  a  heart  of  stone,  must  have 
felt  remorse  to  the  last  hour  of  his  life. 

As   Whewell  f   has   well   asked  :    ^^  Who   that  reads  the 

*  All  the  following  statements,  given  on  the  authority  of  these  two 
naturalists,  are  taken  from  Kengger's  "  Naturgesch.  der  Saugethiere 
von  Paraguay,"  1830,  s.  41-57,  and  from  Brehm's  "  Thierleben,"  B. 
i,  s.  10-87. 

f  Quoted  by  Dr.  Lauder  Lindsay,  in  his  "  Physiology  of  Mind  in 
the  Lower  Animals  ;  "  "Journal  of  Mental  Science,"  April,  1871,  p. 
38. 

f  "  Bridgewater  Treatise,"  p.  363. 


MENTAL  POWERS.  79 

touching  instances  of  maternal  affection,  related  so  often 
of  the  women  of  all  nations  and  of  the  females  of  all  ani- 
mals, can  doubt  that  the  principle  of  action  is  tlie  same  in 
the  two  cases?"  We  see  maternal  affection  exhibited  in 
the  most  trifling  details;  thus,  Rengger  observed  an  Ameri- 
can monkey  (a  Cebus)  carefully  driving  away  the  flies 
Avhich  plagued  her  infant;  and  Duvaucel  saw  a  H^dobates 
washing  the  faces  of  her  young  ones  in  a  stream.  So  in- 
tense is  the  grief  of  female  monkeys  for  the  loss  of  their 
young  that  it  invariably  caused  the  death  of  certain  kinds 
kept  under  confinement  by  Brehm  in  N.  Africa.  Orphan 
monkeys  were  always  adopted  and  carefully  guarded  by  the 
other  monkeys,  both  males  and  females.  One  female' 
baboon  had  so  capacious  a  heart  that  she  not  only  adopted 
young  monkeys  of  other  species,  but  stole  young  dogs  and 
cats,  which  she  continually  carried  about.  Her  kindness, 
however,  did  not  go  so  far  as  to  share  her  food  with  her 
adopted  offspring,  at  which  Brehm  was  surprised,  as  his 
monke5's  always  divided  everything  quite  fairly  with  their 
own  young  ones.  An  adopted  kitten  scratched  this  affec- 
tionate baboon,  who  certainly  had  a  fine  intellect,  for  she  was 
much  astonished  at  being  scratched,  and  immediately  exam- 
ined the  kit  ten's  feet,  and  without  more  ado  bit  off  the  claws.* 
In  the  Zoological  Gardens  I  heard  from  the  keeper  that  an 
old  baboon  {C.  cliacma)  had  adopted  a  Rhesus  monkey;  but 
when  a  young  drill  and  mandrill  were  placed  in  the  cage 
she  seemed  to  perceive  that  these  monkeys,  though  distinct 
species,  were  her  nearer  relatives,  for  she  at  once  rejected 
the  Rhesus  and  adopted  both  of  them.  The  young  Rhesus, 
as  I  saw,  was  greatly  discontented  at  being  thus  rejected, 
and  it  would,  like  a  naughty  child,  annoy  and  attack  the 
young  drill  and  mandrill  whenever  it  could  do  so  with 
safety;  this  conduct  exciting  great  indignation  in  the  old 
baboon.  Monkeys  will  also,  according  to  Brehm,  defend 
their  master  when  attacked  by  any  one,  as  well  as  dogs  to 
wiiom  they  are  attached,  from  the  attacks  of  other  dogs. 
But  we  here  trench  on  the  subjects  of  sympathy  and  fidel- 
ity, to   which  I  shall  recur.     Some  of  Brehm's  monkeys 

*  A  critic,  without  any  grounds  ("  Quarterly  Review,"  July,  1871, 
p.  72),  disputes  the  possibility  of  this  act  as  described  by  Brehm,  for 
the  sake  of  discrediting  my  work.  Therefore  I  tried,  and  found  that 
I  could  readily  seize  with  my  own  teeth  the  sharp  little  claws  of  a 
kitten  nearly  five  weeks  old. 


80  THE  DESCENT  OF  MAN. 

took  much  delight  in  teasing  a  certain  old  dog  whom  they 
disliked,  as  well  as  other  animals,  in  various  ingenious  ways. 

Most  of  the  more  complex  emotions  are  common  to  the 
higher  animals  and  ourselves.  Every  one  has  seen  how 
jealous  a  dog  is  of  his  master's  affection  if  lavished  on  any 
other  creature;  and  I  have  observed  the  same  fact  with 
monkeys.  This  shows  that  animals  not  only  love,  hut  have 
a  desire  to  be  loved.  Animals  manifestly  feel  emulation. 
They  love  approbation  or  praise;  and  a  dog  carrying  a  bas- 
ket for  his  master  exhibits  in  a  high  degree  self-complac- 
ency or  pride.  There  can,  I  think,  be  no  doubt  that  a  dog 
feels  shame,  as  distinct  from  fear,  and  something  very  like 
modesty  when  begging  too  often  for  food.  A  great  dog 
scorns  the  snarling  of  a  little  dog,  and  this  may  be  called 
magnanimity.  Several  observers  have  stated  that  monkeys 
certainly  dislike  being  laughed  at;  and  they  sometimes  in- 
vent imaginary  offenses.  In  the  Zoological  Gardens  I  saw 
a  baboon  who  always  got  into  a  furious  rage  when  his  keeper 
took  out  a  letter  or  book  and  read  it  aloud  to  him;  and  his 
rage  was  so  violent  that,  as  I  witnessed  on  one  occasion,  he 
bit  his  own  leg  till  the  blood  flowed.  Dogs  show  what  may 
be  fairly  called  a  sense  of  humor  as  distinct  from  mere  play; 
if  a  bit  of  stick  or  other  such  object  be  thrown  to  one,  he 
will  often  carry  it  away  for  a  short  distance  ;  and  then 
squatting  down  with  it  on  the  ground  close  before  him,  will 
wait  until  his  master  comes  quite  close  to  take  it  away. 
The  dog  will  then  seize  it  and  rush  away  in  triumph,  re- 
peating the  same  maneuver,  and  evidently  enjoying  the 
practical  joke. 

We  will  now  turn  to  the  more  intellectual  emotions  and 
faculties,  which  are  very  important,  as  forming  the  basis 
for  the  development  of  the  higher  mental  powers.  Animals 
manifestly  enjoy  excitement,  and  suff'er  from  ennui,  as  may 
be  seen  with  dogs,  and,  according  to  Rengger,  with  mon- 
keys. All  animals  feel  Wonder  and  many  exhibit  Curiosity. 
They  sometimes  suffer  from  this  latter  quality,  as  when 
the  hunter  plays  antics  and  thus  attracts  them;  I  have  wit- 
nessed this  with  deer,  and  so  it  is  with  the  wary  chamois, 
and  with  some  kinds  of  wild-ducks.  Brehm  gives  a  curious 
account  of  the  instinctive  dread,  which  his  monkeys  exhib- 
ited, for  snakes;  but  their  curiosity  was  so  great  that  they 
could  not  desist  from  occasionally  satiating  their  horror 
in  a  most  human  fashion  by  lifting  up  the  lid  of  the  box 


MENTAL  POWERS.  81 

in  which  the  snakes  were  kept.  I  was  so  much  surprised 
at  his  account  that  I  took  a  stuffed  and  coiled-up  snake 
into  the  monkey-house  at  the  Zoological  Gardens,  and  the 
excitement  thus  caused  was  one  of  the  most  curious  spec- 
tacles which  I  ever  beheld.  Three  species  of  Cercopithecus 
were  the  most  alarmed  ;  they  dashed  about  their  cages  and 
uttered  sharp  signal  cries  of  danger,  which  were  understood 
by  the  other  monkeys.  A  few  young  monkeys  and  one  old 
Anubis  baboon  alone  took  no  notice  of  the  snake.  I  then 
placed  the  stuffed  specimen  on  the  ground  in  one  of  the 
larger  compartments.  After  a  time  all  the  monkeys  col- 
lected round  it  in  a  large  circle,  and,  staring  intently,  pre- 
sented a  most  ludicrous  appearance.  They  became  ex- 
tremely nervous;  so  that  when  a  wooden  ball,  with  which 
they  were  familiar  as  a  plaything,  was  accidentally  moved 
in  the  strawy  under  which  it  was  partly  hidden,  they  all  in- 
stantly started  away.  These  monkeys  behaved  very  dif- 
ferently when  a  dead  fish,  a  mouse,*  a  li\dng  turtle,  and 
other  new  objects  were  placed  in  their  cages;  for  though  at 
first  frightened,  they  soon  approached,  handled  and  ex- 
amined them.  I  then  placed -a  live  snake  in  a  paper  bag, 
with  the  mouth  loosely  closed,  in  one  of  the  larger  com- 
partments. One  of  the  monkeys  immediately  approached, 
cautiously  opened  the  bag  a  little,  peeped  in,  and  instantly 
dashed  away.  Then  I  witnessed  what  Brehm  has  described, 
for  monkey  after  monkey,  with  head  raised  high  and  turned 
on  one  side,  could  not  resist  taking  a  momentary  peep  into 
the  upright  bag,  at  the  dreadful  object  lying  quietly  at  the 
bottom.  It  would  almost  appear  as  if  monkeys  had  some 
notion  of  zoological  affinities,  for  those  kept  by  Brehm  ex- 
hibited a  strange,  though  mistaken,  instinctive  dread  of 
innocent  lizards  and  frogs.  An  orang,  also,  has  been 
known  to  be  much  alarmed  at  the  first  sight  of  a  turtle,  f 
The  principle  of  Imitation  is  strong  in  man,  and  espe- 
cially, as  I  have  myself  observed,  with  savages.  In  certain 
morbid  states  of  the  brain  this  tendency  is  exaggerated  to  an 
extraordinary  degree;  some  hemiplegic  patients  and  others, 
at  the  commencement  of  inflammatory  softening  of  the  brain, 
unconsciously  imitate  every  word  which  is  uttered,  whether 

*  I  have  given  a  short  account  of  their  behavior  on  this  occasion  iu 
my  •'  Expression  of  the  Emotions,"  p.  43. 

t  W,  C.  L.  Martin,  "  Nat.  Hist,  of  Mammalia,"  1841,  p.  405. 


82  THE  DESCENT  OF  MAN, 

in  their  own  or  in  a  foreign  language,  and  every  ges'  are  or 
action  which  is  performed  near  them.*  Desorf  has  re- 
marked tliat  no  animal  voluntarily  imitates  an  action  per- 
formed by  man,  until  in  the  ascending  scale  we  come  to 
monkeys,  which  are  well  known  to  be  ridiculous  mockers. 
Animals,  however,  sometimes  imitate  each  other^s  actions  ; 
thus  two  species  of  wolves,  which  had  been  reared  by  dogs, 
learned  to  bark,  as  does  sometimes  the  ^jackal 4  but  whether 
this  can  be  called  voluntary  imitation  is  another  question. 
Birds  imitate  the  songs  of  their  parents,  and  sometimes  of 
other  birds;  and  parrots  are  notorious  imitators  of  any  sound 
Avhich  they  often  hear.  Dureau  de  la  Malle  gives  an  account§ 
of  a  dog  reared  by  a  cat^  Who  learned  to  imitate  the  well- 
known  action  of  a  cat  lickiflg  her  paws,  and  thus  washing 
her  ears  and  face;  thi^  was  also  witnessed  by  the  celebrated 
naturalist  Audouin.  I  have  received  several  confirmatory 
accounts;  in  one  of  these,  a  dog  had  not  been  suckled  by  a 
cat,  but  had  been  brought  Up  with  one,  together  with 
kittens,  and  had  thus  acquired  the  above  habit,  which  he 
ever  afterward  practiced  during  his  life  of  thirteen  years. 
Dureau  dela  Malla's  dog  likewise  learned  from  the  kittens 
to  play  with  a  ball  by  rolling  it  about  with  his  fore  paws 
and  springing  on  it.  A  correspondent  assures  me  that  a 
cat  in  his  house  used  to  put  her  paws  into  jugs  of  milk 
having  too  narrow  a  mouth  for  her  head.  A  kitten  of  this 
cat  soon  learned  the  same  trick,  and  practiced  it  ever 
afterward  whenever  there  was  an  opportunity. 

The  parents  of  many  animals,  trusting  to  the  principle 
of  imitation  in  their  young,  and  more  especially  to  their 
instinctive  or  inherited  tendencies,  may  be  said  to  educate 
them.  We  see  this  when  a  cat  brings  a  live  mouse  to  her 
kittens;  and  Dureau  de  la  Malle  has  given  a  curious  ac- 
count (in  the  paper  above  quoted)  of  his  observations  on 
hawks  which  taught  their  young  dexterity,  as  well  as  judg- 
ment of  distances,  by  first  dropping  through  the  air  dead 
mice  and  sparrows,  which  the  young  generally  failed  to 

*Dr.  Bateman  "  On  Aphasia."  1870,  p.  110. 

f  QuQted  by  Vogt,  "  Memoire  sur  les  Microcephales,"  1867,  p.  168. 

X  "  The  Variation  of  Animals  and  Plants  under  Domestication,"  vol, 

i,  p.  27. 

g  "  Anuales  des  Sc.  Nat."  (1st  series),  torn,  xxii,  p.  397, 


MENTAL  POWERS.  -83 

catch,  and  then  bringing  them  live  birds  and  letting  them 
loose. 

I  Hardly  any  faculty  is  more  important  for  the  intellectual 
progress  of  man  than  Attention.  Animals  clearly  manifest 
this  power,  as  when  a  cat  watches  by  a  hole  and  prepares 
to  spring  on  its  prey.  Wild  animals  sometimes  become  so 
absorbed  when  thus  engaged  that  they  may  be  easily  ap- 
proached. Mr.  Bartlett  has  given  me  a  curious  proof  how 
variable  this  faculty  is  in  monkeys.  A  man  who  trains 
monkeys  to  act  in  plays  used  to  purchase  common  kinds 
from  the  Zoological  Society  at  the  price  of  five  pounds  for 
each;  but  he  ottered  to  give  double  the  price  if  he  might 
keep  three  or  four  of  them  for  a  few  days  in  order  to  select 
one.  When  asked  how  he  could  possibly  learn  so  soon 
whether  a  particular  monkey  would  turn  out  a  good  actor, 
he  answered  that  it  all  depended  on  their  power  of  atten- 
tion. If  when  he  was  talking  and  explaining  anything  to 
a  monkey  its  attention  was  easily  distracted,  as  by  a  fly  on 
the  wall  or  other  trifling  object,  the  case  was  hopeless.  If 
he  tried  by  punishment  to  make  an  inattentive  monkey  act 
it  turned  sulky.  On  the  other  hand,  a  monkey  which 
carefully  attended  to  him  could  always  be  trained. 

It  is  almost  superfluous  to  state  that  animals  have  excel- 
ent  ')7j£mories  for  persons  and  places.  A  baboon  at  the 
Cape  oiCrood  Hope,  as  I  have  been  informed  by  Sir  An- 
drew Smith,  recognized  him  with  joy  after  an  absence  of 
nine  months.  I  had  a  dog  who  was  savage  and  averse  to 
all  strangers,  and  I  purposely  tried  his  memory  after  an 
absense  of  five  years  and  two  days.  I  went  near  the  stable 
where  he  lived  and  shouted  to  him  in  my  old  manner;  he 
showed  no  joy,  but  instantly  followed  me  out  walking,  and 
obeyed  me  exactly  as  if  I  had  parted  with  him  only  half  an 
hour  before.  A  train  of  old  associations,  dormant  during 
five  years,  had  thus  been  instantaneously  awakened  in  his 
mind.  Even  ants,  as  P.  Huber*  has  clearly  shown,  recog- 
nized their  fellow-ants  belonging  to  the  same  community 
after  a  separation  of  four  months.  Animals  can  certainly 
by  some  means  judge  of  the  intervals  of  time  between 
recurrent  events. 

The  Imagination  is  one  of  the  highest  prerogatives  of 
man.     By  this  faculty  he  unites  former  images  and  ideas, 

*  "Les  Mceurs  des  Fourmis,"  1810,  p.  150. 


k 


84  THE  DESCENT  OF  MAN. 

independently  of  the  will^  and  thus  creates  brilliant  and 
novel  results.  A  poet,  as  Jean  Paul  Richter  remarks,* 
"who  must  reflect  whether  he  shall  make  a  character  say 
yes  or  no — to  the  devil  with  him  ;  he  is  only  a  stupid 
corpse."  Dreaming  gives  us  the  best  notion  of  this  power; 
as  Jean  Paul  again  says,  ' '  The  dream  is  an  involuntary  art 
of  poetry."  The  value  of  the  products  of  our  imagination 
depends  of  course  on  the  number,  accuracy,  and  clearness 
of  our  impressions,  on  our  judgment  and  taste  in  selecting 
or  rejecting  the  involuntary  combinations,  and  to  a  certain 
extent  on  our  power  of  voluntarily  combining  them.  As 
dogs,  cats,  horses,  and  probably  all  the  higher  animals, 
even  birds  f  have  vivid  dreams,  and  this  is  shown  by  their 
movements  and  the  sounds  uttered,  we  must  admit  that 
they  possess  some  power  of  imagination.  There  must  be 
something  special  which  causes  dogs  to  howl  in  the  night, 
and  especially  during  moonlight,  in  that  remarkable  and 
melancholy  manner  called  baying.  All  dogs  do  not  do  so; 
and,  according  to  Houzeau,];  they  do  not  then  look  at  the 
moon,  but  at  some  lixed  point  near  the  horizon.  Houzeau 
thinks  that  their  imaginations  are  disturbed  by  the  vague 
outlines  of  the  surrounding  objects,  and  conjure  up  before 
them  fantastic  images  ;  if  this  be  so,  their  feelings  may 
almost  be  called  superstitious. 

I  Of  all  the  faculties  of  the  human  mind,  it  will,  I  pre- 
sume, be  admitted  that  R^aWii  stands  at  the  summit.  Only 
a  few  persons  now  dispute  that  animals  possess  some  power 
of  reasoning.  Animals  may  constantly  be  seen  to  pause, 
deliberate,  and  resolve.  It  is  a  significant  fact,  that  the 
more  the  habits  of  any  particular  animal  are  studied  by  a 
naturalist,  the  more  he  attributes  to  reason  and  the  less  to 
unlearned  instincts.  §  In  future  chapters  we  shall  see  that 
some  animals  extremely  low  in  the  scale  apparently  display 

*  Quoted  in  Dr.  Maudsley's  "  Physiology  and  Pathology  of  Mind," 
1868,  pp.  19,  220. 

f  Dr.  Jerdon,  "Birds  of  India,"  vol.  i,  1862,  p.  21.  Houzeau  says 
that  his  paroquets  and  canary  birds  dreamed:  "  Facultes  Mentales," 
torn,  ii,  p.  136. 

X  "Facultes  Mentales  des  Animaux,"  1872,  torn,  ii,  p.  181. 

§Mr.  L.  H,  Morgan's  work  on  "The  American  Beaver,"  1868, 
offers  a  good  illustration  of  this  remark.  I  cannot  help  thinking, 
however,  that  he  goes  too  far  in  underrating  the  power  of  instinct. 


MENTAL  P0WER8.  85 

a  certain  amount  of  reason.  Xo  doubt  it  is  often  difficult 
to  distinguish  between  the  power  of  reason  and  that  of  in- 
stinct. For  instance.  Dr.  Hayes,  in  his  work  on  "The 
Open  Polar  Sea,''  repeatedly  remarks  that  his  dogs,  instead 
of  continuing  to  draw  the  sledges  in  a  compact  body, 
diverged  and  separated  when  they  came  to  thin  ice,  so  that 
their  weight  might  be  more  evenly  distributed.  This  was 
often  the  first  warning  which  the  travelers  received  that  the 
ice  was  becoming  thin  and  dangerous.  Xow,  did  the  dogs 
act  thus  from  the  experience  of  each  individual,  or  from 
ttie  example  of  the  older  and  wiser  dogs,  or  from  an  inher- 
ited habit,  that  is,  from  instinct?  This  instinct,  may  pos- 
sibly have  arisen  since  the  time,  long  ago,  when  dogs  were 
first  employed  by  the  natives  in  drawing  their  sledges;  or 
the  Arctic  wolves,  the  parent-stock  of  the  Esquimau  dog, 
may  have  acquired  an  instinct  impelling  them  not  to  attack 
their  prey  in  a  close  pack,  when  on  thin  ice. 

We  can  only  judge  by  the  circumstances  under  which 
actions  are  performed,  whether  they  are  due  to  instinct,  or 
to  reason,  or  to  the  mere  association  of  ideas;  this  latter 
principle,  however,  is  intimately  connected  with  reason.  A 
curious  case  has  been  given  by  Prof.  Mobius,*  of  a  pike, 
separated  by  a  plate  of  glass  from  an  adjoining  aquarium 
stocked  with  fish,  and  who  often  dashed  himself  with  such 
violence  against  the  glass  in  trying  to  catch  the  oiher  fishes, 
that  he  was  sometimes  completely  stunned.  The  pike  went 
on  thus  for  three  months,  but  at  last  learned  caution,  and 
ceased  to  do  so.  The  plate  of  glass  was  then  removed,  but 
the  pike  would  not  attack  these  particular  fishes,  though  he 
w^ould  devour  others  which  were  afterward  introduced  ;  so 
strongly  was  the  idea  of  a  violent  shock  associated  in  his 
feeble  mind  with  the  attempt  on  his  former  neighbors.  If 
a  savage,  who  had  never  seen  a  large  plate-glass  window, 
were  to  dash  himself  even  once  against  it,  he  would  for  a 
long  time  afterward  associate  a  shock  with  a  window-frame; 
but,  very  differently  from  the  pike,  he  would  probably 
reflect  on  the  nature  of  the  impediment,  and  be  cautious 
under  analogous  circumstances.  Xow  with  monkeys,  as  we 
shall  presently  see,  a  painful  or  merely  a  disagreeable 
impression,  from  an  action  once  j)erformed,  is  sometimes 
sufficient  to  prevent  the  animal  from  repeating  it.     If  we 

*  '*  Die  Bewegungen  der  Tliiere,"  etc.,  1873,  p.  11. 


g6  THE!  DESCENT  OF  MAN. 

attribute  this  difference  between  the  monkey  and  the  piko 
solely  to  the  association  of  ideas  being  so  much  stronger 
and  more  persistent  in  the  one  than  the  other,  though  the 
pike  often  received  much  the  more  severe  injury,  can  we 
maintain  in  the  case  of  man  that  a  similar  difference 
implies  the  possession  of  a  fundamentally  different  mind? 

Houzeau  relates  *  that,  while  crossing  a  wide  and  arid 
plain  in  Texas,  his  two  dogs  suffered  greatly  from  thirst, 
and  that  between  thirty  and  forty  times  they  rushed  down 
the  hollows  to  search  for  water.  These  hollows  were  not 
valleys,  and  there  were  no  trees  in  them,  or  any  other  differ- 
ence in  the  vegetation,  and,  as  they  were  absolutely  dry, 
there  could  have  been  no  smell  of  damp  earth.  The  dogs 
behaved  as  if  they  knew  that  a  dip  in  the  ground  offered 
them  the  best  chance  of  finding  water,  and  Houzeau  has 
oftened  witnessed  the  same  behavior  in  other  animals. 

I  have  seen,  as  I  dare  say  have  others,  that  when  a  small 
object  is  thrown  on  the  ground  beyond  the  reach  of  one  of 
the  elephants  in  the  Zoological  Gardens,  he  blows  through 
his  trunk  on  the  ground  beyond  the  object,  so  that  the  cur- 
rent reflected  on  all  sides  may  drive  the  object  within  his 
reach.  Again,  a  well-known  ethnologist,  Mr.  Westropp, 
informs  me  that  he  observed  in  Vienna  a  bear  deliberately 
making  with  his  paw  a  current  in  some  water,  which  was 
close  to  the  bars  of  his  cage,  so  as  to  draw  a  piece  of  float- 
ing bread  within  his  reach.  These  actions  of  the  elephant 
and  bear  can  hardly  be  attributed  to  instinct  or  inherited 
habit,  as  they  would  be  of  little  use  to  an  animal  in  a  state 
of  nature.  Now,  what  is  the  difference  between  such 
actions,  when  performed  by  an  uncultivated  man,  and  by 
one  of  the  higher  animals? 

The  savage  and  the  dog  have  often  found  water  at  a  low 
level,  and  the  coincidence  under  such  circumstances  has 
become  associated  in  their  minds.  A  cultivated  man 
would  perhaps  make  some  general  proposition  on  the  sub- 
ject; but  from  all  that  we  know  of  savages  it  is  extremely 
doubtful  whether  they  would  do  so,  and  a  dog  certainly 
would  not.  But  a  savage,  as  well  as  a  dog,  would  search 
.n  tlie  same  way,  though  frequently  disappointed,  and  in 
])otli  it  seems  to  be  equally  an  act  of  reason,  whether  or  not 
any  general  j^roposition  on  the  subject  is  consciously  placed 

*Facult6s  Mentales  des  Animaux,"  1872,  torn.  ii.  p.  265. 


MENTAL  POWERS.  87 

before  the  mind.  *  The  same  would  apply  to  the  elephant 
and  the  bear  making  currents  in  the  air  or  water.  The 
savage  would  certainly  neither  know  nor  care  by  what  law 
the  desired  movements  were  effected;  yet  his  act  would  be 
guided  by  a  rude  process  of  reasoning,  as  surely  as  would  a 
philosopher  in  his  longest  chain  of  deductions.  There 
would  no  doubt  be  this  difference  between  him  and  one  of 
the  higher  animals,  that  he  v\^ould  take  notice  of  much 
slighter  circumstances  and  conditions,  and  would  observe 
any  connection  between  them  after  much  less  experience, 
and  this  would  be  of  paramount  importance.  I  kept  a 
daily  record  of  the  actions  of  one  of  my  infants,  and  when 
he  was  about  eleven  months  old,  and  before  he  could  speak 
a  single  word,  I  was  continualh'  struck  with  the  greater 
quickness  with  which  all  sorts  of  objects  and  sounds  were 
associated  together  in  his  mind,  compared  with  that  of  the 
most  intelligent  dogs  I  ever  knew.  But  the  higher  ani- 
mals differ  in  exactly  the  same  way  in  this  power  of  associ- 
ation from  those  low  in  the  scale,  such  as  the  pike,  as  well 
as  in  that  of  drawing  inferences  and  of  observation. 

The  promptings  of  reason,  after  very  short  experience, 
are  well  shown  by  the  following  actions  of  American  mon- 
keys, which  stand  low  in  their  order.  Rengger,  a  most 
careful  observer,  states  that  when  he  first  gave  eggs  to  his 
monkeys  in  Paraguay  they  smashed  them  and  thus  lost 
much  of  their  contents;  afterward  they  gently  hit  one  end 
against  some  hard  body,  and  picked  off  the  bits  of  shell 
with  their  fingers.  After  cutting  themselves  only  once 
with  any  sharp  tool,  they  would  not  touch  it  again,  or 
would  handle  it  with  the  greatest  caution.  Lumps  of 
sugar  were  often  given  them  wrapped  up  in  paper  ;  and 
Rengger  sometimes  put  a  live  wasp  in  the  paper,  so  that  in 
hastily  unfolding  it  they  got  stung;  after  this  had  once  hap- 
pened they  always  first  held  the  packet  to  their  ears  to  de- 
tect any  movement  within,  f 

*  Prof.  Huxley  lias  analyzed  witli  admirable  clearness  the  mental 
steps  by  which  a  man,  as  well  as  a  dog,  arrives  at  a  conclusion  in  a 
case  analogous  to  that  given  in  my  text.  See  his  article,  "Mr.  Dar- 
win's Critics,"  in  the  "  Contemporary  Review,"  Nov,  1871,  p.  462, 
and  in  his  **  Critiques  and  Essays,"  1873,  p.  279, 

f  Mr.  Belt,  in  his  most  interesting  work,  "The  Naturalist  in  Nic 
aragua,"  1874  (p.  119),  likewise  descril>es  various  actions  of  a  tamed 
Cebus,  which,  1  think,  clearly  s:how  that  this  animal  possessed  some 
reasoning  power. 


88  THE  DESCENT  OF  MAK. 

Tlie  following  cases  relate  to  dogs.  Mr.  Colquhoiin* 
winged  two  wild-ducks,  which  fell  on  the  farther  side  of  a 
stream;  his  retriever  tried  to  bring  over  both  at  once,  but 
could  not  succeed;  she  then,  though  never  before  known  to 
ruffle  a  feather,  deliberately  killed  one,  brought  over 
the  other,  and  returned  for  the  dead  bird.  Col. 
Hutchinson  relates  that  two  partridges  were  shot  at  once, 
one  being  killed,  the  other  wounded;  the  latter  ran  away 
and  was  caught  by  the  retriever,  who  on  her  return  came 
across  the  dead  bird;  ^^she  stopped,  evidently  greatly  puz- 
zled, and  after  one  or  two  trials,  finding  she  could  not  take 
it  up  without  permitting  the  escape  of  the  winged  bird,  she 
considered  a  moment,  then  deliberately  murdered  it  by  giv- 
ing it  a  severe  crunch,  and  afterward  brought  away  both 
together.  This  was  the  only  known  instance  of  her  ever 
having  wilfully  injured  any  game.'''  Here  we  have  reason, 
though  not  quite  perfect,  for  the  retriever  might  have 
brought  the  wounded  bird  first  and  then  returned  for  the 
dead  one,  as  in  the  case  of  the  two  wild-ducks.  I  give  the 
above  cases  as  resting  on  the  evidence  of  two  independent 
witnesses,  and  because  in  both  instances  the  retrievers,  after 
deliberation,  broke  through  a  habit  which  is  inherited  by 
them  (that  of  not  killing  the  game  retrieved),  and  because 
they  show  how  strong  their  reasoning  faculty  must  have 
been  to  overcome  a  fixed  habit. 

I  will  conclude  by  quoting  a  remark  by  the  illustrious 
Humboldt,  t  '^  The  muleteers  in  South  America  say,  ^I 
will  not  give  you  the  mule  whose  step  is  easiest,  but  la  mas 
racional — the  one  that  reasons  best ;' "  and,  as  he  adds, 
^^  this  popular  expression,  dictated  by  long  experience,  com- 
bats the  system  of  animated  machines  better  perhaps  than 
all  the  arguments  of  speculative  philosophy.  Neverthe- 
less some  writers  even  yet  deny  that  the  higher  animals  pos- 
sess a  trace  of  reason;  and  they  endeavor  to  explain  away, 
by  what  appears  to  be  mere  verbiage,  J;  all  such  facts  as  those 
above  given. 

*"The  Moor  and  the  Loch,"  p.  45.  Col.  Hutcliinson  on  "Dog 
Breaking,"  1850,  p.  46. 

f  "  Personal  Narrative,"  Eng.  translat.,  vol.  iii,  p.  106. 

X I  am  glad  to  find  that  so  acute  a  reasoner  as  Mr.  Leslie  Stephen 
("  Darwinism  and  Divinity,  Essays  on  Free-thinking,"  1873,  p.  80). 
in  speaking  of  the  supposed  impassable  barrier  between  the  minds  of 
man  and  the  lower  animals,  says:  "The  distinctions,  indeed,  which 


MENTAL  POWERS.  89 

It  has,  I  think,  now  been  shown  that  man  and  the  higher, 
animals,  especially  the  Primates,  have  some  few  instincte  in; 
common.  All  have  the  same  senses,  intuitions  and  sensa-j 
tions — similar  passions,  affections  and  emotions,  even  the\ 
more  complex  ones,  such  as  jealousy,  suspicion,  emulation,  \ 
gratitude  and  magnanimity;  they  practice  deceit  and  are  I 
revengeful;  they  are  sometimes  susceptible  to  ridicule,  and  I 
even  have  a  sense  of  humor;  they  feel  wonder  and  curiosity;/ 
they  possess  the  same  faculties  of  imitation,  attention,  de-l 
liberation,  choice,  memory,  imagination,  the  association  of  i 
ideas  and  reason,  though  in  very  different  degrees.  The 
individuals  of  the  same  species  graduate  in  intellect  from 
absolute  imbecility  to  high  excellence.  They  are  also  liable 
to  insanity,  though  far  less  often  than  in  the  case  of  man.* 
Nevertheless,  many  authors  have  insisted  that  man  is 
divided  by  an  insuperable  barrier  from  all  the  lower  animals 
in  his  mental  faculties.  I  formerly  made  a  collection  of 
above  a  score  of  such  aphorisms,  but  they  are  almost  worth- 
less, as  their  wide  difference  and  number  prove  the  diffi- 
culty, if  not  the  impossibility,  of  the  attempt.  It  has  been 
asserted  that  man  alone  is  capable  of  progressive  improve- 
ment; that  he  alone  makes  use  of  tools  or  fire,  domesticates 
other  animals,  or  possesses  property;  that  no  animal  has  the 
power  of  abstraction  or  of  forming  general  concepts,  is  self- 
conscious  and  comprehends  itself;  that  no  animal  employs 
language;  that  man  alone  has  a  sense  of  beauty,  is  liable  to 
caprice,  has  the  feeling  of  gratitude,  mystery,  etc. ;  believes 
in  God,  or  is  endowed  with  a  conscience.  I  wiU  hazard  a 
few  remarks  on  the  more  important  and  interesting  of  these 
points. 

Archbishop  Sumner  formerly  maintained  f  that  man 
alone  is  capable  of  progressive  improvement.  That  he  is 
capable  of  incomparably  greater  and  more  rapid  improve- 

Lave  been  drawn,  seem  to  us  to  rest  upon  no  better  foundation  than 
a  great  niany.otber  metaphysical  distinctions  ;  that  is,  the  assumption 
that  because  you  can  give  two  things  different  names,  they  must 
therefore  have  different  natures.  It  is  difficult  to  understand  how 
anybody  who  has  ever  kept  a  dog,  or  seen  an  elephant,  can  have  any 
doubts  as  to  an  animal's  power  of  performing  the  essential  processes 
of  reasoning." 

*See  "Madness  in  Animals,"  by  Dr.  W.  Lauder  Lindsay,  in 
"Journal  of  Mental  Science,"  July,  1871. 

f Quoted  by  Sir  C.  Lyell,  "  Antiquity  of  Man,"  p.  497. 


90  THE  DESCENT  OF  MAN, 

meiit  than  is  any  other  animal,  admits  of  no  dispute;  and 
tliis  is  mainly  due  to  his  power  of  speaking  and  handing 
down  his  acquired  knowledge.  With  animals,  looking  tirst 
to  the  individual,  every  one  who  has  had  any  experience  in 
setting  traps,  knows  that  young  animals  can  be  caught 
much  more  easily  than  old  ones;  and  they  can  be  much 
more  easily  approached  by  an  enemy.  Even  with  respect 
to  old  animals,  it  is  impossible  to  catch  many  in  the  same 
place  and  in  the  same  kind  of  trap,  or  to  destroy  them  by 
the  same  kind  of  poison  ;  yet  it  is  improbable  that  all 
should  have  partaken  of  the  poison^,  and  impossible  that  all 
should  have  been  caught  in  a  trap.  They  must  learn  cau- 
tion by  seeing  their  brethren  caught  or  poisoned.  In  North 
America,  where  the  fur-bearing  animals  have  long  been  pur- 
sued, they  exhibit,  according  to  the  unanimous  testimony  of 
all  observers,  an  almost  incredible  amount  of  sagacity,  caution 
and  cunning;  but  trapping  has  been  there  so  long  carried 
on  that  inheritance  may  possibly  have  come  into  play.  I 
have  received  several  accounts  that  when  telegraphs  are  first 
set  up  in  any  district  many  birds  kill  themselves  by  flying 
against  the  wires,  but  that  in  the  course  of  a  few  years  they 
learn  to  avoid  this  danger  by  seeing,  as  it  would  appear, 
their  comrades  killed.* 

If  we  look  to  successive  generations,  or  to  the  race,  there 
is  no  doubt  that  birds  and  other  animals  gradually  both 
acquire  and  lose  caution  in  relation  to  man  or  other  enemies;! 
and  this  caution  is  certainly  in  chief  part  an  inherited 
habit  or  instinct,  but  in  part  the  result  of  individul  expe- 
rience. A  good  observer,  Leroy,J:  states  that  in  districts 
where  foxes  are  much  hunted  the  young,  on  first  leaving 
their  burrows,  are  incontestably  much  more  wary  than  the 
old  ones  in  districts  where  they  are  not  much  disturbed. 

Our  domestic  dogs  are  descended  from  wolves  and  jackals,  § 
and  though  they  may  not  have  gained  in  cunning,  and  may 

*For  additional  evidence,  with  details,  see  M.  Houzeau,  "Les 
Facultes  Mentales,"  torn,  ii,  1872,  p.  147. 

f  See,  with  respect  to  birds  on  oceanic  islands,  ray  "Journal  of 
Kesearcbes  during  the  voyage  of  the  '  Beagle,' "  1845,  p.  398.  "  Ori- 
gin of  Species,"  5th  edition,  p.  260. 

:}:  "  Lettres  Phil,  sur  I'lntelligence  des  Animaux,"  nouvelle  edit., 

1802,  p.  86. 

§  See  the  evidence  on  this  head  in  chap,  i,  vol.  i,  "  On  the  Varia- 
tion of  Animals  and  Plants  under  Domestication." 


MENTAL  POWERS.  91 

have  lost  in  wariness  and  suspicion,  yet  they  have  pro- 
gressed in  certain  moral  qualities,  such  as  in  affection,  trust- 
worthiness, temper  and  probably  in  general  intelligence. 
The  common  rat  has  conquered  and  beaten  several  other 
species  throughout  Europe,  in  parts  of  North  America, 
New  Zealand,  and  recently  in  Formosa,  as  well  as  on  the 
mainland  of  China.  Mr.  Swinhoe,*  who  describes  these 
two  latter  cases,  attributes  the  victory  of  the  common  rat 
over  the  large  Mus  coning  a  to  its  superior  cunning;  and 
this  latter  quality  may  probably  be  attributed  to  the  habit- 
ual exercise  of  all  its  faculties  in  avoiding  extirpation  by 
man,  as  well  as  to  nearly  all  the  less  cunning  or  weak- 
minded  rats  having  been  continuously  destroyed  by  him. 
It  is,  however,  possible  that  the  success  of  the  common  rat 
may  be  due  to  its  having  possessed  greater  cunning  than  its 
fellow-species  before  it  became  associated  with  man.  To 
maintain,  independently  of  any  direct  evidence,  that  no 
animal  during  the  course  of  ages  has  progressed  in  intellect 
or  other  mental  faculties  is  to  beg  the  question  of  the  evo- 
lution of  species.  We  have  seen  that,  according  to  Lartet, 
existing  mammals  belonging  to  several  orders  have  larger 
brains  than  their  ancient  tertiary  prototypes. 

It  has  often  been  said  that  no  animal  uses  any  tool;  but 
the  chimpanzee  in  a  state  of  nature  cracks  a  native  fruit, 
somewhat  like  a  walnut,  with  a  stone,  f  Rengger J;  easily 
taught  an  American  monkey  thus  to  break  open  hard  palm- 
nuts;  and  afterward  of  its  own  accord  it  used  stones  to 
open  other  kinds  of  nuts,  as  well  as  boxes.  It  thus  also 
removed  the  soft  rind  of  fruit  that  had  a  disagreeable 
flavor.  Another  monkey  was  taught  to  open  the  lid  of  a 
large  box  with  a  stick,  and  afterward  it  used  the  stick  as  a 
lever  to  move  heavy  bodies;  and  I  have  myself  seen  a  young 
orang  put  a  stick  into  a  crevice,  slip  his  hand  to  the  other 
end,  and  use  it  in  the  proper  manner  as  a  lever.  The 
tamed  elephants  in  India  are  well  known  to  break  off 
branches  of  trees  and  use  them  to  drive  away  the  flies;  and 
this  same  act  has  been  observed  in  an  elephant  in  a  state  of 

*  "Proc.  Zoolog.  Soc,"  1864,  p.  186. 

f  Savage  and  Wvman  in  "Boston  Journal  of  Nat.  Hist.,"  vol.  iv, 
1843-44,  p.  383. 

X  "  Saugethiere  von  Paraguay,"  1830,  s.  51-56. 


92  THE  DESCENT  OF  MAN. 

nature.*  I  have  seen  a  young  orang,  when  she  thought 
she  was  going  to  be  whipped,  cover  and  protect  herself 
with  a  blanket  or  straw.  In  these  several  cases  stones  and 
sticks  were  employed  as  implements;  but  they  are  likewise 
used  as  weapons.  Brehmf  states,  on  the  authority  of  the 
well-known  traveler  Schimper,  that  in  Abyssinia  when  the 
baboons  belonging  to  one  species  ( C.  gelada)  descend  in  troops 
from  the  mountains  to  plunder  the  fields  they  sometimes 
encounter  troops  of  another  species  {C.  hamadryas),  and 
then  a  fight  ensues.  The  Geladas  roll  down  great  stones, 
which  the  Hamadryas  try  to  avoid,  and  then  both  species, 
making  a  great  uproar,  rush  furiously  against  each  other. 
Brehm,  when  accompanying  the  Duke  of  Coburg-Gotha, 
aided  in  an  attack  with  firearms  on  a  troop  of  baboons  in 
the  pass  of  Mensa  in  Abyssinia.  The  baboons  in  return 
rolled  so  many  stones  down  the  mountain,  some  as  large  as 
a  man's  head,  that  the  attackers  had  to  beat  a  hasty  retreat; 
and  the  pass  was  actually  closed  for  a  time  against  the 
caravan.  It  deserves  notice  that  these  baboons  thus  acted 
in  concert.  Mr.  Wallace^;  on  three  occasions  saw  female 
orangs,  accompanied  by  their  young,  ^'breaking  off 
branches  and  the  great  spiny  fruit  of  the  Durian  tree,  with 
every  appearance  of  rage;  causing  such  a  shower  of  missiles 
as  effectually  kept  us  from  approaching  too  near  the  tree." 
As  I  have  repeatedly  seen,  a  chimpanzee  will  throw  any 
object  at  hand  at  a  person  who  offends  him;  and  the  before- 
mentioned  baboon  at  the  Cape  of  Good  Hope  prepared  mud 
for  the  purpose. 

In  the  Zoological  Gardens  a  monkey,  which  had  weak 
teeth  used  to  break  open  nuts  with  a  stone;  and  I  was 
assured  by  the  keepers  that  after  using  the  stone  he  hid  it 
in  the  straw,  and  would  not  let  any  other  monkey  touch  it. 
Here,  then,  we  have  the  idea  of  property;  but  this  idea  is 
common  to  every  dog  with  a  bone,  and  to  most  or  all  birds 
with  their  nests. 

The  Duke  of  Argyll§  remarks  that  the  fashioning  of  an 
implement  for  a  special  purpose  is  absolutely  peculiar  to 
man;  and  he  considers  that  this  forms  an  immeasurable 
gulf  between  him  and  the  brutes.     This  is  no  doubt  a  very 

*  The  "  Indian  Field,"  March  4,  1871. 

f  "Thierleben,"B.  i,  s.  79,  82. 

X  "  The  Malay  Archipelago,"  vol.  i,  1869,  p.  87. 

§  "  Primeval  Man,"  1869,  pp.  145,  147. 


MENTAL  POWERS,  93 

important  distinction;  but  there  appears  to  me  much  truth 
in  Sir  J.  Lubbock's  suggestion,*  that  when  primeval  man 
first  used  flint-stones  for  any  purpose,  he  would  have  acci- 
dentally splintered  them,  and  would  then  have  used  the 
sharp  fragments.  From  this  step  it  would  be  a  small  one 
to  break  the  flints  on  purpose,  and  not  a  very  wide  step  to 
fashion  them  rudely.  This  latter  advance,  however,  may 
have  taken  long  ages,  if  we  may  judge  by  the  immense  in- 
terval of  time  which  elapsed  before  the  men  of  the  neolithic 
period  took  to  grinding  and  polishing  their  stone  tools.  In 
breaking  the  flints,  as  Sir  J.  Lubbock  likewise  remarks,, 
sparks  would  have  been  emitted,  and  in  grinding  them  heat 
w^ould  have  been  evolved;  thus  the  two  usual  methods  of 
"  obtaining  fire  may  have  originated."  The  nature  of  fire, 
would  have  been  known  in  the  many  volcanic  regions  where 
lava  occasionally  flows  through  forests.  The  anthropomor- 
phous apes,  guided  probably  by  instinct,  build  for  them- 
selves temporary  platforms;  but  as  many  instincts  are  largely 
controlled  by  reason,  the  simpler  ones,  such  as  this  of  build- 
ing a  platform,  might  readily  pass  into  a  voluntary  and 
conscious  act.  The  orang  is  known  to  cover  itself  at  night 
with  the  leaves  of  the  Pandanus;  and  Brehm  states  that 
one  of  his  baboons  used  to  protect  itself  from  the  heat  of  the 
sun  by  throwing  a  straw-mat  over  its  head.  In  these  sev- 
eral habits,  we  probably  see  the  first  steps  toward  some  of 
the  simpler  arts,  such  as  rude  architecture  and  dress,  as 
they  arose  among  the  early  progenitors  of  man. 

Abstraction,  General  Conceptions,  Self -consciousness, i 
Mental  Individuality. — It  would  be  very  difficult  for  anyj 
one  with  even  much  more  knowledge  than  I  possess  to  de- 
termine how  far  animals  exhibit  any  traces  of  these  high 
mental  powers.  This  difficulty  arises  from  the  impossibility 
of  judging  what  passes  through  the  mind  of  an  animal; 
and  again,  the  fact  that  writers  differ  to  a  great  extent  in 
the  meaning  which  they  attribute  to  the  above  terms, 
cauBes  a  further  difficulty.  If  one  may  judge  from 
various  articles  which  have  been  published  lately,  the  great- 
est stress  seems  to  be  laid  on  the  supposed  entire  absence 
in  animals  of  the  power  of  abstraction,  or  of  forming  general 
concepts.     But  when  a  dog  sees  another  dog  at  a  distance, 

*  "  Prehistoric  Times,"  1865,  p.  473,  etc. 


94  THIiJ  DESCENT  OF  MAN. 

it  is  often  clear  that  he  perceives  that  it  is  a  dog  in  the 
abstract;  for  when  he  gets  nearer  his  whole  manner  sud- 
denly changes,  if  the  other  dog  be  a  friend.  A  recent 
writer  remarks,  that  in  all  such  cases  it  is  a  pure  assump- 
tion to  assert  that  the  mental  act  is  not  essentially  of  the 
same  nature  in  the  animal  as  in  man.  If  either  refers  what 
he  perceives  with  his  senses  to  a  mental  concept,  then  so  do 
both.*  When  I  say  to  my  terrier,  in  an  eager  voice  (and  I 
have  made  the  trial  many  times),  "  Hi,  hi,  where  is  it?"  she 
at  once  takes  it  as  a  sign  that  something  is  to  be  hunted, 
and  generally  first  looks  quickly  all  around,  and  then 
rushes  into  the  nearest  thicket,  to  scent  for  any  game,  but 
finding  nothing,  she  looks  up  into  any  neighboring  tree  for 
a  squirrel.  Now  do  not  these  actions  clearly  show  that  she 
had  in  her  mind  a  general  idea  or  concept  that  some  ani- 
mal is  to  be  discovered  and  hunted? 

It  may  be  freely  admitted  that  no  animal  is  self-conscious, 
if  by  this  term  it  is  implied,  that  he  reflects  on  such  points, 
as  whence  he  comes  or  whither  he  will  go,  or  what  is  life 
and  death,  and  so  forth.  But  how  can  we  feel  sure  that 
an  old  dog  with  an  excellent  memory  and  some  power  of 
imagination,  as  shown  by  his  dreams,  never  reflects  on  his 
past  pleasures  or  pains  in  the  chase?  And  this  would  be  a 
form  of  self-consciousness.  On  the  other  hand,  as  Biichnert 
has  remarked,  how  little  can  the  hard-worked  wife  of  a  de- 
graded Australian  savage,  who  uses  very  few  abstract  words, 
and  cannot  count  above  four,  exert  her  self -consciousness, 
or  reflect  on  the  nature  of  her  own  existence.  It  is  gener- 
ally admitted  that  the  higher  animals  possess  memory,  at- 
tention, association,  and  even  some  imagination  and  reason. 
If  these  powers,  which  differ  much  in  different  animals,  are 
capable  of  improvement,  there  seems  no  great  improbability 
in  more  complex  faculties,  such  as  the  higher  forms  of  ab- 
straction, and  self -consciousness,  etc.,  having  been  evolved 
through  the  development  and  combination  of  the  simpler 
ones.  It  has  been  urged  against  the  views  here  maintained 
that  it  is  impossible  to  say  at  what  point  in  the  ascending 
scale  animals  become  capable  of  abstraction,  etc. ;  but  who 
can  say  at  what  age  this  occurs  in  our  young  children? 

*Mr.  Hookham,  in  a  letter  to  Prof.  Max  Miiller,  in  the  "Birm- 
ingbani  News,"  May  1873. 

f  "  Conferences  sur  la  Theorie  Darvvinienne,"  French  translat., 
1869,  p.  132. 


MENTAL  POWERS.  95 

We  see  at  least  that  such  powers  are  developed  in  children 
by  imperceptible  degrees. 

That  animals  retain  their  mental  individuality  is  unques- 
tionable. When  my  voice  awakened  a  train  of  old  associa- 
tions in  the  mind  of  the  before-mentioned  dog,  he  must 
have  retained  his  mental  individuality,  although  every  atom 
of  his  brain  had  probably  undergone  change  more  than 
once  during  the  interval  of  five  years.  This  dog  might 
have  brought  forward  the  argument  lately  advanced  to 
crush  all  evolutionists,  and  said:  **  I  abide  amid  all  mental 
moods  and  all  material  changes.  .  .  .  The  teaching 
that  atoms  leave  their  impressions  as  legacies  to  other  atoms 
falling  into  the  places  they  have  vacated  is  contradictory  of 
the  utterance  of  consciousness,  and  is  therefore  false;  but  it 
is  the  teaching  necessitated  by  evolutionism,  consequently 
the  hypothesis  is  a  false  one. "  * 

Language. — This  faculty  has  justly  been  considered  as 
one  of  the  chief  distinctions  between  man  and  the  lower 
animals.  But  man,  as  a  highly  competent  judge. 
Archbishop  Whately  remarks,  '^  is  not  the  only  animal  that 
can  make  use  of  language  to  express  what  is  passing  in  his 
mind,  and  can  understand,  more  or  less,  what  is  so  ex- 
pressed by  another,  ^^t  I^  Paraguay  the  Cebiis  azarcB  when 
excited  utters  at  least  six  distinct  sounds,  w^hich  excite  in 
other  monkeys  similar  emotions.  |  The  movements  of  the 
features  and  gestures  of  monkeys  are  understood  by  us,  and 
they  partly  understand  ours,  as  Rengger  and  others  declare. 
It  is  a  more  remarkable  fact  that  the  dog,  since  being 
domesticated,  has  learned  to  bark§  in  at  least  four  or  five 
distinct  tones.  Although  barking  is  a  new  art,  no  doubt 
the  wild  parent-species  of  the  dog  expressed  their  feelings 
by  cries  of  various  kinds.  With  the  domesticated  dog  we 
have  the  bark  of  eagerness,  as  in  the  chase;  that  of  anger, 
as  well  as  growling;  the  yelp  or  howl  of  despair,  as  when 
shut  up;  the  baying  at  night;  the  bark  of  joy,  as  when 
starting  on  a  walk  with  his  master;  and  the  very  distinct 

*The  Rev.  Dr.  J.  M'Cann,  "  Anti-Darwinism,"  1869,  p.  13. 
f  Quoted  in  "Anthropological  Review,"  1864,  p.  158. 
X  Rengger,  ibid,  s.  45. 

§  See  my  "  Variation  of  Animals  and  Plants  under  Domestication," 
vol  i,  p.  ^7. 


96  THE  DESCENT  OF  MAN. 

one  of  demand  or  supplication,  as  wlien  wishing  for  a  door 
or  window  to  be  opened.  According  to  Hoiizeau,  who  paid 
particular  attention  to  the  subject,  the  domestic  fowl  utters 
at  least  a  dozen  significant  sounds.* 

The  habitual  use  of  articulate  language  is,  however, 
peculiar  to  man;  but  he  uses,  in  common  with  the  lower 
animals,  inarticulate  cries  to  express  his  meaning,  aided  by 
gestures  and  the  movements  of  the  muscles  of  the  face,  f 
This  specially  holds  good  with  the  more  simple  and  vivid 
feelings,  which  are  but  little  connected  with  our  higher 
intelligence.  Our  cries  of  pain,  fear,  surprise,  anger,  to- 
gether with  their  appropriate  actions,  and  the  murmur  of  a 
mother  to  her  beloved  child,  are  more  expressive  than  any 
words.  That  which  distinguishes  man  from  the  lower  ani- 
mals is  not  the  understanding  of  articulate  sounds,  for,  as 
every  one  knows,  dogs  understand  many  words  and  sen- 
tences. In  this  respect  they  are  at  the  same  stage  of  devel- 
opment as  infants,  between  the  ages  of  ten  and  twelve 
months,  who  understand  many  words  and  short  sentences, 
but  cannot  yet  utter  a  single  word.  It  is  not  the  mere  ar- 
ticulation which  is  our  distinguishing  character,  for  parrots 
and  other  birds  possess  this  power.  Nor  is  it  the  mere 
capacity  of  connecting  definite  sounds  with  definite  ideas; 
for  it  is  certain  that  some  parrots,  which  have  been  taught 
to  speak,  connect  unerringly  words  with  things  and  per- 
sons with   events.  I     The  lower  animals  differ  from  man 

*  "  Facultes  Mentales  des  Animaux,"  torn,  ii,  1872,  pp.  346-349. 

f  See  a  discussion  on  this  subject  in  Mr.  E.  B.  Tylor's  very  inter- 
esting work,  '*  Researches  into  the  Early  History  of  Mankind,"  1865, 
chaps,  ii  to  iv. 

X  I  have  received  several  detailed  accounts  to  this  effect.  Admiral 
Sir  B,  J.  Sulivan,  whom  I  know  to  be  a  careful  observer,  assures  me 
that  an  African  parrot,  long  kept  in  his  father's  house,  invariably 
called  certain  persons  of  the  household,  as  well  as  visitors,  by  their 
names.  He  said  "good  morning"  to  every  one  at  breakfast,  and 
"good  night"  to  each  as  they  left  the  room  at  night,  and  never  re- 
versed these  salutations.  To  Sir  B.  J.  Sulivan's  father,  he  used  to 
add  to  the  "good  morning"  a  short  sentence,  which  was  never  once 
repeated  after  his  father's  death.  He  scolded  violently  a  strange 
dog  which  came  into  the  room  through  the  open  window;  and  he 
scolded  another  parrot  (saying  "you  naughty  polly  ")  which  had  got 
out  of  its  cage,  and  was  eating  apples  on  the  kitchen  table.  See 
also,  to  the  same  effect,  Houzeau  on  parrots,  "  Facultes  Mentales," 
tom.  ii,  p.  309.  Dr.  A.  Moschkau  informs  me  that  he  knew  a  star- 
ling which  never  made  a  mistake  in  saying  in  German  "  good  morn- 
ing "  to  persons  arriving,  and  "good-by,  old  fellow,"  to  those  de- 
parting.    I  could  add  several  other  such  cases. 


MENTAL  POWERS.  97 

solely  in  his  almost  infinitely  larger  power  of  associating 
together  the  most  diversified  sounds  and  ideas,  and  this 
obviously  depends  on  the  high  development  of  his  mental 
powers. 

As  Home  Tooke,  one  of  the  founders  of  the  noble  science 
of  philology,  observes,  language  is  an  art,  like  brewing  or 
baking;  but  writing  would  have  been  a  better  simile.  It 
certainly  is  not  a  true  instinct,  for  every  language  has  to  be 
learned.  It  differs,  however,  widely  from  all  ordinary  arts, 
for  man  has  an  instinctive  tendency  to  speak,  as  we  see  in 
the  babble  of  our  young  children;  while  no  child  has  an 
instinctive  tendency  to  brew,  bake,  or  write.  Moreover,  no 
philologist  now  supposes  that  any  language  has  been  delib- 
erately invented;  it  has  been  slowly  and  unconsciously  de- 
veloped by  many  steps.*  The  sounds  uttered  by  birds 
offer  in  several  respects  the  nearest  analogy  to  language, 
for  all  the  members  of  the  same  species  utter  the  same  in- 
stinctive cries  expressive  of  their  emotions;  and  all  the 
kinds  which  sing  exert  their  power  instinctively;  but  the 
actual  song,  and  even  the  call-notes,  are  learned  from  their 
parents  or  foster-parents.  These  sounds,  as  Daines  Bar- 
ringtonf  has  proved,  "  are  no  more  innate  than  language 
is  in  man.^'  The  first  attempts  to  sing  "  may  be  compared 
to  the  imperfect  endeavor  in  a  child  to  babble."  The 
young  males  continue  practicing,  or  as  the  bird-catchers 
say,  *' recording,"  for  ten  or  eleven  months.  Their  first 
essays  show  hardly  a  rudiment  of  the  future  song;  but  as 
they  grow  older  we  can  perceive  what  they  are  aiming  at; 
and  at  last  they  are  said  "  to  sing  their  song  round." 
Nestlings  which  have  learned  the  song  of  a  distinct  species, 
as  with  the  canary  birds  educated  in  the  Tyrol,  teach  and 
transmit  their  new  song  to  their  offspring.  The  slight 
natural  differences  of  song  in  the  same  species  inhabiting 
dift'erent  districts  may  be  appositely  compared,  as  Barring- 

*  See  some  good  remarks  on  this  head  by  Prof.  Whitney,  in  his 
'•  Oriental  and  Linguistic  Studies,"  1873,  p.  354.  He  observes  that 
the  desire  of  communication  between  man  is  the  living  force,  which, 
in  the  development  of  language,  "works  both  consciously  and  un- 
consciously; consciously  as  regards  the  immediate  end  to  be  attained; 
unconsciously  as  regards  the  further  consequences  of  the  act." 

f  Hon.  Daines  Barrington  in  "Philosoph.  Transactions,"  1773,  p. 
262.  See  also  Dureau  de  la  Malle,  in  "Ann.  des.  Sc.  Nat.,"  3d 
series,  Zoolog.  tom.  x,  p.  119. 


98  THE  DESCENT  OF  MAN. 

ton  remarks,  "to  provincial  dialects;"  and  the  songs  of 
allied  though  distinct  species  may  be  compared  with  the 
languages  of  distinct  races  of  man.  I  have  given  the  fore- 
going details  to  show  that  an  instinctive  tendency  to 
acquire  an  art  is  not  peculiar  to  man. 

With  respect  to  the  origin  of  articulate  language,  after 
having  read  on  the  one  side  the  highly  interesting  works  of 
Mr.  Hensleigh  Wedgwood,  the  Rev.  F.  Farrar,  and  Prof. 
Schleicher,*  and  the  celebrated  lectures  of  Prof.  Max  Mul- 
ler  on  the  other  side,  I  cannot  doubt  that  language  owes  its 
origin  to  the  imitation  and  modification  of  various  natural 
sounds,  the  voices  of  other  animals  and  man^s  own  instinctive 
cries,  aided  by  signs  and  gestures.  When  we  treat  of  sexual 
selection  we  shall  see  that  primeval  man,  or  rather  some 
early  progenitor  of  man,  probably  first  used  his  voice  in 
producing  true  musical  cadences,  that  is  in  singing,  as  do 
some  of  the  gibbon-apes  at  the  present  day;  and  we  may 
conclude  from  a  widely-spread  analogy,  that  this  power 
would  have  been  especially  exerted  during  the  courtship  of 
the  sexes — would  have  expressed  various  emotions,  such  as 
love,  jealousy,  triumph — and  would  have  served  as  a  chal- 
lenge to  rivals.  It  is,  therefore,  probable  that  the  imita- 
tion of  musical  cries  by  articulate  sounds  may  have  given 
rise  to  words  expressive  of  various  complex  emotions.  The 
strong  tendency  in  our  nearest  allies,  the  monkeys,  in 
microcephalous  idiots,  \  and  in  the  barbarous  races  of  man- 
kind, to  imitate  whatever  they  hear  deserves  notice,  as 
bearing  on  the  subject  of  imitation.  Since  monkeys  cer- 
tainly understand  much  that  is  said  to  them  by  man,  and 
when  wild,  utter  signal-cries  of  danger  to  their  fellows;  \ 
and  since  fowls  give  distinct  warnings  for  danger  on  the 
ground,  or  in  the  sky  from  hawks  (both,  as  well  as  a  third 

*  "  On  the  Origin  of  Language,"  by  H.  Wedgwoou,  1866.  "Clia]!- 
ters  on  Language,"  b\  the  Kev.  F.  W.  Farrar,  1865.  These  works 
are  most  interesting.  See  also  "  De  la  Phys.  et  de  Parole,"  par 
Albert  Lemoine,  1865,  p.  190.  The  work  on  this  subject,  by  the  late 
Prof.  Aug.  Schleicher  nas  been  translated  by  Dr.  Bikkers  into  En- 
glish, under  the  title  of  "Darwinism  tested  by  the  Science  of  Lan 
guage,"  1869. 

fVogt,  "  Meraoire  sur  les  Microc  phales,"  1867,  p.  169.  With 
respect  to  savages,  I  have  given  some  facts  in  my  "  Journal  of  Re- 
{-•earches,"  etc.,  1845,  p.  206. 

X  See  clear  evidence  on  this  head  in  the  two  works  so  often  quoted, 
by  Brehm  and  liengger. 


MENTAL  POWERS.  99 

cry,  intelligible  to  dogs*),  may  not  some  unusually  wise 
ape-like  animal  have  imitated  the  growl  of  a  beast  of  prey, 
and  thus  told  his  fellow-monkeys  the  nature  of  the  expected 
danger?  This  would  have  been  a  first  step  in  the  forma- 
tion of  a  language. 

As  the  voice  was  used  more  and  more,  the  vocal  organs 
would  have  been  strengthened  and  perfected  through  the 
principle  of  the  inherited  effects  of  use;  and  this  would 
have  reacted  on  the  power  of  speech.  But  the  relation  be- 
tween the  continued  use  of  language  and  the  development 
of  the  brain,  has  no  doubt  been  far  more  important.  The 
mental  powers  in  some  early  progenitor  of  man  must  have 
been  more  highly  developed  than  in  any  existing  ape, 
before  even  the  most  imperfect  form  of  speech  could  have 
come  into  use;  but  we  may  confidently  believe  that  the 
continued  use  and  advancement  of  this  power  would  have 
reacted  on  the  mind  itself,  by  enabling  and  encouraging  it 
to  carry  on  long  trains  of  thought.  A  complex  train  of 
thought  can  no  more  be  carried  on  without  the  aid  of 
words,  whether  spoken  or  silent,  than  a  long  calculation 
without  the  use  of  figures  or  algebra.  It  appears,  also, 
that  even  an  ordinary  train  of  thought  almost  requires,  or 
is  greatly  facilitated  by  some  form  of  language,  for  the 
dumb,  deaf,  and  blind  girl,  Laura  Bridgman,  was  observed 
to  use  her  fingers  while  dreaming,  f  Nevertheless,  a  long 
succession  of  vivid  and  connected  ideas  may  pass  through 
the  mind  without  the  aid  of  any  form  of  language,  as  we 
may  infer  from  the  movements  of  dogs  during  their 
dreams.  AVe  have,  also,  seen  that  animals  are  able  to 
reason  to  a  certain  extent,  manifestly  without  the  aid  of 
language.  The  intimate  connection  between  the  brain,  as 
it  is  now  developed  in  us,  and  the  faculty  of  speech,  is 
well  shown  by  those  curious  cases  of  brain-disease  in  which 
speech  is  specially  affected,  as  when  the  power  to  remem- 
ber substantives  is  lost,  while  other  words  can  be  correctly 
used,  or  where  substantives  of  a  certain  class,  or  all 
except    the    initial    letters   of    substantives    and    proper 

*  Houzeau  gives  a  very  curious  account  of  his  observations  on  this 
subject  in  his  "  Facultes  Mentales  des  Animaux,"  torn,  ii,  p.  348. 

f  See  remarks  on  this  head  by  Dr.  Maudsley,  "  The  Physiology 
and  Pathology  of  Mind,"  2d  edit..  1868,  p.  198. 


100  THE  DESCENT  OF  MAN. 

names  are  forgotten.*  There  is  no  more  improbability  in 
continued  use  of  the  mental  and  vocal  organs  leading  to 
inherited  changes  in  their  structure  and  functions,  than  in 
the  case  of  handwriting,  which  depends  partly  on  the  form 
of  the  hand  and  partly  on  the  disposition  of  the  mind;  and 
handwriting  is  certainly  inherited,  f 

Several  writers,  more  especially  Prof.  MaxMuller,J;  have 
lately  insisted  that  the  use  of  language  implies  the  power  of 
forming  general  concepts;  and  that  as  no  animals  are  sup- 
posed to  possess  this  power,  an  impassable  barrier  is  formed 
between  them  and  man.§  With  respect-to  animals,  I  have 
already  endeavored  to  show  that  they  have  this  power,  at 
least  in  a  rude  and  incipient  degree.  As  far  as  concerns 
infants  of  from  ten  to  eleven  months  old,  and  deaf-mutes, 
it  seems  to  me  incredible  that  they  should  be  able  to  con- 
nect certain  sounds  with  certain  general  ideas  as  quiciily  as 
they  do,  unless  such  ideas  were  already  formed  in  their 
minds.  The  same  remark  may  be  extended  to  the  more 
intelligent  animals;  as  Mr.  Leslie  Stephen  observes,]   ^^A 

*  Many  curious  cases  liave  been  recorded.  See,  for  instance.  Dr. 
Bateman,  "  On  Aphasia,"  1870,  pp.  27,  31,  53,  100,  etc.  Also,  "  In 
quiries  Concerning  the  Intellectual  Powers,"  by  Dr.  Abercrombie, 
1838,  p.  150. 

f  "  The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  p.  6, 

X  Lectures  on  "Mr.  Darwin's  Philosophy  of  Language,"  1873. 

§The  judgment  of  a  distinguished  philologist,  such  as  Prof,  Whit- 
ney, will  have  far  more  weight  on  this  point  than  anything  that  I 
can  say.  He  remarks  ("  Oriental  and  Linguistic  Studies,"  1873,  p. 
297),  in  speaking  of  Bleek's  views:  "Because  on  the  grand  scale 
language  is  the  necessary  auxiliary  of  thought,  indispensable  to  tlie 
development  of  the  power  of  thinking,  to  the  distinctness  and  variety 
and  complexity  of  cognitions  to  the  full  mastery  of  consciousness; 
therefore  he  would  fain  make  thought  absolutely  impossible  without 
speech,  identifying  the  faculty  with  its  instrument.  He  might  just 
as  reasonably  assert  that  the  human  hand  cannot  act  without  a  tool. 
With  such  a  doctrine  to  start  from,  he  cannot  stop  short  of  Mtiller's 
worst  paradoxes,  that  an  infant  {in  fans,  not  speaking)  is  not  a 
human  being,  and  that  deaf-mutes  do  not  become  possessed  of  reason 
until  they  learn  to  twist  their  fingers  into  imitation  of  spoken 
words."  Max  Mliller  gives  in  italics  ("  Lectures  on  Mp.  Darwin's 
Philosophy  of  Language,"  1873,  third  lecture)  the  following  aphor- 
ism: "There  is  no  thought  without  words,  as  little  as  there  are 
words  without  thought."  What  a  strange  definition  must  here  be 
given  to  the  word  thought. 

I  "  Essays  on  Fyee-thinking,"  etc.,  1873;  p.  8§. 


MENTAL  POWERS.  101 

dog  frames  a  general  concept  of  cats  or  sheep,  and  knows 
tlie  corresponding  words  as  well  as  a  philosopher.  And  the 
capacity  to  understand  is  as  good  a  proof  of  vocal  intelli- 
gence, though  in  an  inferior  degree,  as  the  capacity  to 
speak." 

Why  the  organs  now  used  for  speech  should  have  been 
originally  perfected  for  this  purpose,  rather  than  any  other 
organs,  it  is  not  difficult  to  see.  Ants  have  considerable 
powers  of  intercommunication,  by  means  of  their  antennae, 
as  shown  by  Huber,  who  devotes  a  whole  chapter  to  their 
language.  We  might  have  used  our  fingers  as  efficient  in- 
struments, for  a  person  with  practice  can  report  to  a  deaf  man 
every  word  of  a  speech  rapidly  delivered  at  a  public  meeting; 
but  the  loss  of  our  hands  while  thus  employed  would  have 
been  a  serious  inconvenience.  As  all  the  higher  mammals 
possess  vocal  organs,  constructed  on  the  same  general  plan  as 
ours,  and  used  as  a  means  of  communication,  it  was  ob- 
viously probable  that  these  same  organs  would  be  still  further 
developed  if  the  power  of  communication  hadtobe  improved; 
and  this  has  been  effected  by  the  aid  of  adjoining  and  well 
adapted  parts,  namely,  the  tongue  and  lips.*  The  fact  of 
the  higher  apes  not  using  their  vocal  organs  for  speech,  no 
doubt  depends  on  their  intelligence  not  having  been  suffi- 
ciently advanced.  The  possession  by  them  of  organs,  which 
with  long-continued  practice  might  have  been  used  for 
speech,  although  not  thus  used,  is  paralleled  by  the  case  of 
many  birds  which  possess  organs  fitted  for  singing,  though 
they  never  sing.  Thus,  the  nightingale  and  crow  have 
vocal  organs  similarly  constructed,  these  being  used  by  the 
former  for  divei*sified  song,  and  by  the  latter  only  for  croak- 
ing, f  If  it  be  asked  why  apes  have  not  had  their  intellects 
developed  to  the  same  degree  as  that  of  man,  general  causes 
only  can  be  assigned  in  answer,  and  it  is  unreasonable  to 
expect  anything  more  definite,  considering  our.  ignorance 

*See  some  good  remarks  to  this  effect  by  Dr.  Maudsley,  "The 
Physiology  and  Pathology  of  Mind,"  1868,  p.  199. 

t Macgillivray,  "Hist,  of  British  Birds,"  vol.  ii,  1839,  p.  29.  An 
excellent  observer,  Mr.  Blackwall,  remarks  that  the  magpie  learns  to 
pronounce  single  words,  and  even  short  sentences,  more  readily  than 
almost  any  other  British  bird;  yet,  as  he  adds,  after  long  and  closely 
investigating  its  habits,  he  has  never  known  it,  in  a  state  of  nature, 
displav  anv  unusual  capacity  for  imitation.  "  Researches  in  Zool- 
ogy," 1834,  p.  158. 


102  THE  DESCENT  OF  MAN. 

with  respect  to  the  successive  stages  of  development  through 
which  each  creature  has  passed. 

The  formation  of  different  languages  and  of  distinct 
species,  and  the  proofs  that  both  have  been  developed 
through  a  gradual  process,  are  curiously  parallel.*  But  we 
can  trace  the  formation  of  many  words  further  back  than 
that  of  species,  for  we  can  perceive  how  they  actually  arose 
from  the  imitation  of  various  sounds.  We  find  in  distinct 
languages  striking  homologies  due  to  community  of  de- 
scent, and  analogies  due  to  a  similar  process  of  formation. 
The  manner  in  which  certain  letters  or  sounds  change 
when  others  change  is  very  like  correlated  growth.  We 
have  in  both  cases  the  reduplication  of  parts,  the  effects  of 
long-continued  use,  and  so  forth.  '  The  frequent  presence 
of  rudiments,  both  in  languages  and  in  species,  is  still  more 
remarkable.  The  letter  m  in  the  word  am,  means  /;  so 
that  in  the  expression  1  am,  a  superfluous  and  useless  rudi- 
ment has  been  retained.  In  the  spelling  also  of  words,  let- 
ters often  remain  as  the  rudiments  of  ancient  forms  of  pro- 
nunciation. Languages,  like  organic  beings,  can  be  classed 
in  groups  under  groups;  and  they  can  be  classed  either  nat- 
urally according  to  descent,  or  artificially  by  other  charac- 
ters. Dominant  languages  and  dialects  spread  widely,  and 
lead  to  the  gradual  extinction  of  other  tongues.  A  lan- 
guage like  a  species,  when  once  extinct,  never,  as  Sir  0.  Lyell 
remarks,  reappears.  The  same  language  never  has  two 
birth-places.  Distinct  languages  may  be  crossed  or  blended 
together,  f  We  see  variability  in  every  tongue,  and  new 
words  are  continually  cropping  up;  but  as  there  is  a  limit 
to  the  powers  of  the  memory,  single  words,  like  whole  lan- 
guages, gradually  become  extinct.  As  Max  MiillerJ;  has 
well  remarked:  '^  A  struggle  for  life  is  constantly  going  on 
among  the  words  and  grammatical  forms  in  each  language. 
The  better,  the  shorter,  the  easier  forms  are  constantly 
gaining  the  upper  hand,  and  they  owe  their  success  to  their 
own  inherent  virtue. ^^     To  these  more  important  causes  of 

*  See  the  very  interesting  parallelism  between  the  development  of 
species  and  languages,  given  by  Sir  C.  Lyell  in  "The  Geolog.  Evi- 
dences of  the  Antiquity  of  Man,"  1863,  chap,  xxiii. 

f  See  remarks  to  this  effect  by  the  Hev.  F.  W.  Farrar,  in  an  inter- 
esting article,  entitled  "Philology  and  Darwinism,"  in  "Nature," 
March  24,  1870,  p.  528. 

X  "  Nature,"  Jan.  6,  1870,  p.  257. 


MENTAL  POWERS.  ^03 

the  survival  of  certain  words  mere  novelty  and  fashion  may 
be  added;  for  there  is  in  tlie  mind  of  man  a  strong  love  for 
slight  changes  in  all  things.  The  survival  or  preservation 
of  certain  favored  words  in  the  struggle  for  existence  is 
natural  selection. 

The  perfectly  regular  and  wonderfully  complex  con- 
struction of  the  languages  of  many  barbarous  nations  has 
often  been  advanced  as  a  proof,  either  of  the  divine  origin 
of  these  languages,  or  of  the  high  art  and  former  civiliza- 
tion of  their  founders.  Thus  F.  von  Schlegel  writes:  "In 
those  languages  which  appear  to  be  at  the  lowest  grade  of 
intellectual  culture,  we  fully  observe  a  very  high  and  elaborate 
degree  of  art  in  their  grammatical  structure.  This  is  espe- 
cially the  case  with  the  Basque  and  the  Lapponian,  and 
many  of  the  American  languages."*  But  it  is  assuredly 
an  error  to  speak  of  any  language  as  an  art,  in  the  sense  of 
its  having  been  elaborately  and  methodically  formed.  Philol- 
ogists now  admit  that  conjugations,  declensions,  etc., 
originally  existed  as  distinct  words,  since  Joined  together  ; 
and  as  such  words  express  the  most  obvious  relations  be- 
tween objects  and  persons,  it  is  not  surprising  that  they 
should  have  been  used  by  the  men  of  most  races  during  the 
earliest  ages.  With  respect  to  perfection,  the  following 
illustration  will  best  show  how  easily  we  may  err;  a  Crinoid 
sometimes  consists  of  no  less  than  150,000  pieces  of  shell, f 
all  arranged  with  perfect  symmetry  in  radiating  lines;  but 
a  naturalist  does  not  consider  an  animal  of  this  kind  as 
more  perfect  than  a  bilateral  one  with  comparatively  few 
parts,  and  with  none  of  these  parts  alike,  excepting  on  the 
opposite  sides  of  the  body.  He  justly  considers  the  differ- 
entiation and  specialization  of  organs  as  the  test  of  perfec- 
tion. So  with  languages;  the  most  symmetrical  and  com- 
plex ought  not  to  be  ranked  above  irregular,  abbreviated, 
and  bastardized  languages,  which  have  borrowed  expressive 
words  and  useful  forms  of  construction  from  various  con- 
quering, conquered  or  immigrant  races. 

From  those  few  and  imperfect  remarks  I  conclude  that 
the  extremely  complex  and  regular  construction  of  many 
barbarous  languages,  is  no  proof  that  they  owe  their  origin 

*  Quoted  by  C.  S.  Wake,  "  Cliapters  on  Man,"  1868,  p.  101. 
f  Buckland,  "  Bridgewater  Treatise,"  p.  411. 


104  THE  DESCENT  OF  MAN, 

to  a  special  act  of  creation.*  Nor,  as  we  have  seen,  does 
the  faculty  of  articulate  speech  in  itself  offer  any  insuper- 
able objection  to  the  belief  that  man  has  been  developed 
from  some  lower  form. 

Sense  of  Beauty. — This  sense  has  been  declared  to  be 
peculiar  to  man.  I  refer  here  only  to  the  pleasure  given  by 
certain  colors,  forms  and  sounds,  and  which  may  fairly  be 
called  a  sense  of  the  beautiful;  with  cultivated  men  such 
sensations  are,  however,  intimately  associated  with  complex 
ideas  and  trains  of  thought.  When  we  behold  a  male  bird 
elaborately  displaying  his  graceful  plumes  or  splendid  colors 
before  the  female,  while  other  birds,  not  thus  decorated, 
make  no  such  display,  it  is  impossible  to  doubt  that  she 
admires  the  beauty  of  her  male  partner.  As  women  every- 
where deck  themselves  with  these  plumes,  the  beauty  of 
such  ornaments  cannot  be  disputed.  As  we  shall  see  later, 
the  nests  of  humming-birds,  and  the  playing  passages  of 
bower-birds  are  tastefully  ornamented  with  gayly-colored  ob- 
jects ;  and  this  shows  that  they  must  receive  some  kind  of  pleas- 
ure from  the  sight  of  such  things.  With  the  great  majority 
of  animals,  however,  the  taste  for  the  beautiful  is  confined, 
as  far  as  we  can  judge,  to  the  attractions  of  the  opposite 
sex.  The  sweet  strains  poured  forth  by  many  male  birds 
during  the  season  of  love  are  certainly  admired  by  the 
females,  of  which  fact  evidence  will  hereafter  be  given.  If 
female  birds  had  been  incapable  of  appreciating  the  beauti- 
ful colors,  the  ornaments  and  voices  of  their  male  partners, 
all  the  labor  and  anxiety  exhibited  by  the  latter  in  display- 
ing their. charms  before  the  females  would  have  been  thrown 
away;  and  this  it  is  impossible  to  admit.  Why  certain 
bright  colors  should  excite  pleasure  cannot,  I  presume,  be 
explained  any  more  than  why  certain  flavors  and  scents  are 
agreeable;  but  habit  has  something  to  do  with  the  result, 
for  that  which  is  at  first  unpleasant  to  our  senses  ultimately 
becomes  pleasant,  and  habits  are  inherited.  With  respect 
to  sounds,  Helmholtz  has  explained  to  a  certain  extent  on 
physiological  principles  why  harmonies  and  certain  cadences 
are  agreeable.  But  besides  this,  sounds  frequently  recur- 
ring at  irregular  intervals  are  highly  disagreeable,  as  every 

See  some  good  remarks  on  tlie  simplification  of  languages,  by 
Sir  J.  Lubbock,  "  Origin  of  Civilization,"  1870,  p.  278. 


MENTAL  POWERS,  105 

one  will  admit  who  has  listened  at  night  to  the  irregular 
flapping  of  a  rope  on  board  ship.  The  same  principle  seems 
to  come  into  play  with  vision,  as  the  eye  prefers  symmetry 
or  figures  with  some  regular  recurrence.  Patterns  of  this 
kind  are  employed  by  even  the  lowest  savages  as  ornaments; 
and  they  have  been  developed  through  sexual  selection  for 
the  adornment  of  some  male  animals.  Whether  we  can  or 
not  give  any  reason  for  the  pleasure  thus  derived  from  vision 
and  hearing,  yet  man  and  many  of  the  lower  animals  are 
alike  pleased  by  the  same  colors,  graceful  shading  and 
forms,  and  the  same  sounds. 

The  taste  for  the  beautiful,  at  least  as  far  as  female 
beauty  is  concerned,  is  not  of  a  special  nature  in  the  human 
mind;  for  it  dilt'ers  widely  in  the  diilerent  races  of  man, 
and  is  not  quite  the  same  even  in  the  different  nations  of 
the  same  race.  Judging  from  the  hideous  ornaments  and 
the  equally  hideous  music  admired  by  most  savages,  it  might 
be  urged  that  their  aesthetic  faculty  was  not  so  highly  de- 
veloped as  in  certain  animals,  for  instance,  as  in  birds. 
Obviously  no  animal  would  be  capable  of  admiring  such 
scenes  as  the  heavens  at  night,  a  beautiful  landscape,  or 
refined  music;  but  such  high  tastes  are  acquired  through 
culture,  and  depend  on  complex  associations;  they  are  not 
enjoyed  by  barbarians  or  by  uneducated  persons. 

Many  of  the  faculties,  which  have  been  of  inestimable 
service  to  man  for  his  progressive  advancement,  such  as  the 
powers  of  the  imagination,  wonder,  curiosity,  an  undefined 
sense  of  beauty,  a  tendency  to  imitation,  and  the  love  of 
excitement  or  novelty,  could  hardly  fail  to  lead  to  capricious 
changes  of  customs  and  fashions.  I  have  alluded  to  this 
point  because  a  recent  writer*  has  oddly  fixed  on  Caprice 
^'  as  one  of  the  most  remarkable  and  typical  differences  be- 
tween savages  and  brutes.^''  But  not  only  can  we  partially 
understand  how  it  is  that  man  is  from  various  conflicting 
influences  rendered  capricious,  but  that  the  lower  animals 
are,  as  we  shall  hereafter  see,  likewise  capricious  in  their 
affections,  aversions,  and  sense  of  beauty.  There  is  also 
reason  to  suspect  that  they  love  novelty  for  its  own  sake. 

Belief  in  God — Religion. — There  is  no  evidence  that 
man  was  aboriginally  endowed  with  the  ennobling  belief  in 

*  "  The  Spectator,"  Dec.  4,  1869,  p.  1430. 


lOG  THE  DESCENT  OF  MAN. 

the  existence  of  an  Omnipotent  God.  On  the  contrary- 
there  is  ample  evidence,  derived  not  from  hasty  travelers, 
but  from  men  who  have  long  resided  with  savages,  that 
numerous  races  have  existed,  and  still  exist,  who  have  no 
idea  of  one  or  more  gods,  and  who  have  no  words  in  their 
languages  to  express  such  an  idea.*  The  question  is  of 
course  wholly  distinct  from  that  higher  one,  whether  there 
exists  a  Creator  and  Ruler  of  the  universe;  and  this  has 
been  answered  in  the  affirmative  by  some  of  the  highest 
intellects  that  have  ever  existed. 

If,  however,  we  include  under  the  term  ^^ religion"  the 
belief  in  unseen  or  spiritual  agencies,  the  case  is  wholly 
different;  for  this  belief  seems  to  be  universal  with  the  less 
civilized  races.  Nor  is  it  difficult  to  comprehend  how  it 
arose.  As  soon  as  the  important  faculties  of  the  imagina- 
tion, wonder,  and  curiosity,  together  with  some  power  of 
reasoning,  had  become  partially  developed,  man  would 
naturally  crave  to  understand  what  was  passing  around  him, 
and  would  have  vaguely  speculated  on  his  own  existence. 
As  Mr.  McLennan  f  has  remarked,  "  Some  explanation  of 
the  phenomena  of  life,  a  man  must  feign  for  himself,  and 
to  judge  from  the  universality  of  it,  the  simplest  hypothe- 
sis, and  the  first  to  occur  to  men,  seems  to  have  been  that 
natural  phenomena  are  ascribable  to  the  presence  in 
animals,  plants,  and  things,  and  in  the  forces  of  nature,  of 
such  spirits  prompting  to  action  as  men  are  conscious  they 
themselves  possess."  It  is  also  probable,  as  Mr.  Tylor  has 
shown,  that  dreams  may  have  first  given  rise  to  the  notion 
of  spirits;  for  savages  do  not  readily  distinguish  between 
subjective  and  objective  impressions.  When  a  savage 
dreams,  the  figures  which  appear  before  him  are  believed  to 
have  come  from  a  distance,  and  to  stand  over  him;  or  ^'  the 
soul  of  the  dreamer  goes  out  on  its  travels,  and  comes 
home  with  a  remembrance  of  what  it  has  seen."  J     But 

*  See  an  excellent  article  on  this  subject  by  the  Rev.  F.  W.  Farrar, 
in  the  "Anthropological  Review,"  Aug.,  1864,  p.  217.  For  fur- 
ther facts  see  Sir  J.  Lubbock,  "Prehistoric  Times,"  2d  edit.,  1869,  p. 
564;  and  especially  the  chapters  on  Religion  in  his  "  Origin  of  Civil- 
ization," 1870, 

f  "  The  Worship  of  Animals  and  Plants,"  in  the  "  Fortnightly  Re- 
view," Oct.  1,  1869,  p.  422. 

J  Tylor,  "Early  History  of  Mankind,"  1865,  p.  6.  See  also  the 
three  striking  chapters  on  tlie  Development  of  Religion,  in  Lub- 
bock's "  Origin  of  Civilization,"  1870.     In  a  like  manner  Mr.  Herbert 


MENTAL  POWERS.  107 

until  the  faculties  of  imagination,  curiosity,  reason,  etc., 
had  been  fairly  well  developed  in  the  mind  of  man,  his 
dreams  would  not  have  led  him  to  believe  in  spirits,  any 
more  than  in  the  case  of  a  dog. 

The  tendency  in  savages  to  imagine  that  natural  objects 
and  agencies  are  animated  by  spiritual  or  living  essences,  is 
perhaps  illustrated  by  a  little  fact  which  I  once  noticed; 
my  dog,  a  full-grown  and  very  sensible  animal,  was  lying 
on  the  lawn  during  a  hot  and  still  day;  but  at  a  little  dis- 
tance a  slight  breeze  occasionally  moved  an  open  parasol, 
which  would  have  been  wholly  disregarded  by  the  dog  had 
any  one  stood  near  it.  As  it  was,  every  time  that  the  par- 
asol slightly  moved  the  dog  growled  fiercely  and  barked. 
He  must,  I  think,  have  reasoned  to  himself  in  a  rapid  and 
unconscious  manner  that  movement  without  any  apparent 
cause  indicated  the  presence  of  some  strange  living  agent, 
and  that  no  stranger  had  a  right  to  be  on  his  territory. 

The  belief  in  spiritual  agencies  would  easily  pass  into  the 
belief  in  the  existence  of  one  or  more  gods.  For  savages 
would  naturally  attribute  to  spirits  the  same  passions,  the 
same  love  of  vengeance  or  simplest  form  of  justice,  and  the 
same  affections  which  they  themselves  feel.  The  Fuegians 
appear  to  be  in  this  respect  in  an  intermediate  condition, 
for  when  the  surgeon  on  board  the  "Beagle"  shot  some 
young  ducklings  as  specimens  York  Minster  declared  in 
the  most  solemn  manner:  "  Oh,  Mr.  BjTioe,  much  rain, 
much  snow,  blow  much;"  and  this  was  evidently  a  retribu- 
tive punishment  for  wasting  human  food.  So  again  he 
related  how,  when  his  brother  killed  a  •'  wild  man,"  storms 
long  raged,  much  rain  and  snow  fell.     Yet  we  could  never 

Spencer,  in  his  ingenious  essay  in  the  **  Fortnightly  Review  "  (May 
1,  1870,  p.  535),  accounts  for  the  earlier  forms  of  religious  belief 
throughout  the  world,  by  man  being  led  through  dreams,  shadows, 
and  other  causes,  to  look  at  himself  as  a  double  essence,  corporeal 
and  spiritual.  As  the  spiritual  being  is  supposed  to  exist  after  death 
and  to  be  powerful,  it  is  propitiated  by  various  gifts  and  ceremonies, 
and  its  aid  invoked.  He  then  further  shows  that  names  or  nick- 
names given  from  some  animal  or  other  object,  to  the  early  progeni- 
tors or  founders  of  a  tribe,  are  supposed  after  a  long  interval  to  rep- 
resent the  real  progenitor  of  the  tribe;  and  such  animal  or  object  is 
then  naturally  believed  still  to  exist  as  a  spirit,  is  held  sacred,  and 
worshiped  as  a  god.  Nevertheless  I  cannot  but  suspect  that  there  is 
a  still  earlier  and  ruder  stage,  when  anything  which  manifests 
power  or  movement  is  thought  to  l>e  endowed  with  some  form  of 
Hfe,  and  with  mental  faculties  analogous  to  our  own. 


108  THE  DESCENT  OF  MAN. 

discover  that  the  Euegians  believed  in  what  we  should  call  a 
God  or  practiced  any  religious  rites;  and  Jemmy  Button, 
with  justifiable  pride,  stoutly  maintained  that  there  was  no 
devil  in  his  land.  This  latter  assertion  is  the  more  remark- 
able, as  with  savages  the  belief  in  bad  spirits  is  far  more 
common  than  that  in  good  ones. 

The  feeling  of  religious  devotion  is  a  highly  complex 
one,  consisting  of  love,  complete  submission  to  an  exalted 
and  mysterious  superior,  a  strong  sense  of  dependence,* 
fear,  reverence,  gratitude,  hope  for  the  future,  and  per- 
haps other  elements.  No  being  could  experience  so  com- 
plex an  emotion  until  advanced  in  his  intellectual  and 
moral  faculties  to  at  least  a  moderately  high  level.  Never- 
theless, we  see  some  distant  approach  to  this  state  of  mind 
in  the  deep  love  of  a  dog  for  his  master,  associated  with 
complete  submission,  some  fear,  and  perhaps  other  feelings. 
The  behavior  of  a  dog  when  returning  to  his  master  after 
an  absence,  and,  as  I  may  add,  of  a  monkey  to  his  beloved 
keeper,  is  widely  different  from  that  toward  their  fellows. 
In  the  latter  case  the  transports  of  joy  appear  to  be  some- 
what less,  and  the  sense  of  equality  is  shown  in  every 
action.  Prof.  Braubach  goes  so  far  as  to  maintain  that  a 
dog  looks  on  his  master  as  on  a  god.f 

The  same  high  mental  faculties  which  first  led  man  to 
believe  in  unseen  spiritual  agencies,  then  in  fetichism, 
polytheism,  and  ultimately  in  monotheism,  would  infallibly 
lead  him,  as  long  as  his  reasoning  powers  remained  poorly 
developed,  to  various  strange  superstitions  and  customs. 
Many  of  these  are  terrible  to  think  of — such  as  the  sacrifice 
of  human  beings  to  a  blood-loving  god;  the  trial  of  inno- 
cent persons  by  the  ordeal  of  poison  or  fire,  witchcraft, 
etc. — yet  it  is  well  occasionally  to  reflect  on  these  supersti- 
tions, for  they  show  us  what  an  infinite  debt  of  gratitude 
we  owe  to  the  improvement  of  our  reason,  to  science,  and 
to  our  accumulated  knowledge.     As  Sir  J.  LubbockJ;  has 

*  See  an  able  article  on  the  * '  Physical  Elements  of  Religion, "  by 
Mr.  L.  Owen  Pike,  in  "  Anthropolog.  Review,"  April,   1870,  p.   63. 

f  "  Religion,  Moral,  etc.,  der  Darwin'schen  Art-Lehre,"  1869,  s. 
53.  It  is  said  (Dr.  W.  Lauder  Lindsay,  "Journal  of  Mental 
Science,"  1871,  p.  43),  that  Bacon  long  ago,  and  the  poet  Burns,  held 
the  same  notion. 

:t  "  Prehistoric  Times,"  2d  edit.,  p.  571.  In  this  work  (p.  571) 
there  will  be  found  an  excellent  account  of  the  many  strange  and 
capricious  customs  of  savages. 


MENTAL  POWERS.  109 

well  observed,  **  it  is  not  too  much  to  say  that  the  horrible 
dread  of  unknown  evil  hangs  like  a  thick  cloud  over  savage 
life  and  embitters  every  pleasure."  The  miserable  and 
indirect  consequences  of  our  highest  faculties  may  be  com- 
pared with  the  incidental  and  occasional  mistakes  of  the 
instincts  of  the  lower  animals. 


110  THE  DESCENT  OF  MAN. 


CHAPTER  IV. 

COMPARISON  OF  THE   MENTAL   POWERS   OF  MAN   AND  THE 

LOWER  ANIMALS. — Continued. 

The  moral  sense — Fundamental  proposition — The  qualities  of  social 
animals — Origin  of  sociability — Struggle  between  opposed  in- 
stincts— Man  a  social  animal — The  more  enduring  social  instincts 
conquer  other  less  persistent  instincts — The  social  virtues  alone  re- 
garded by  savages — The  self- regarding  virtues  acquired  at  a 
later  stage  of  development — The  importance  of  the  judgment  of 
the  members  of  the  same  community  on  conduct — Transmission 
of  moral  tendencies — Summary. 

I  FULLY  subscribe  to  the  judgment  of  those  writers*  who 
jmaintain  that  of  all  the  differences  between  man  and  the 
lower  animals,  the  moral  sense  or  conscience  is  by  far  the 
most  important.  This  sense,  as  Mackintosh  f  remarks, 
"  has  a  rightful  supremacy  over  every  other  principle  of 
human  action;^'  it  is  summed  up  in  that  short  but  imperi- 
ous word  ought,  so  full  of  high  significance.  It  is  the  most 
noble  of  all  the  attributes  of  man,  leading  him  without  a 
moment's  hesitation  to  risk  his  life  for  that  of  a  fellow- 
creature;  or  after  due  deliberation,  impelled  simply  by  the 
deep  feeling  of  right  or  duty,  to  sacrifice  it  in  some  great 
cause.  Immanuel  Kant  exclaims  :  ^'  Duty  !  Wondrous 
thought,  that  workest  neither  by  fond  insinuation,  flattery, 
nor  by  any  threat,  but  merely  by  holding  up  thy  naked  law 
in  the  soul,  and  so  extorting  for  thyself  always  reverence,  if 
not  always  obedience;  before  whom  all  appetites  are  dumb, 
however  secretly  they  rebel;  whence  thy  original ?''  J 

*See,  for  instance,  on  this  subject,  Quatrefages,  ''Unite  de  I'Es- 
pece  Humaine,"  1861,  p.  21,  etc. 

f  '•  Dissertation  on  Ethical  Philosophy,"  1837,  p.  231,  etc. 

:j: '•  Metaphysics  of  Ethics,"  translated  by  J.   W.   Semple,    Edin- 
burgh, 1836,  p.  136- 


MORAL  SENSE.       '  HI 

This  great  qnestion  has  been  discussed  by  many  writers  * 
of  consummate  ability;  and  my  sole  excuse  for  touching  on 
it,  is  the  impossibility  of  here  passing  it  over;  and  because, 
as  far  as  I  know,  no  "one  has  approached  it  exclusively  from 
the  side  of  natural  history.  The  investigation  possesses, 
also,  some  independent  interest,  as  an  attempt  to  see  how 
far  the  study  of  the  lower  animals  throws  light  on  one  of 
the  hignest  psychical  faculties  of  man. 

The  following  proposition  seems  to  me  in  a  high  degi*ee 
probaoie — namely;  that  any  animal  whatever,  endowed  with 
well-mariied  social  instincts,!  the  parental  and  filial  affec- 
tions being  here  included,  would  inevitably  acquire  a 
moral  sense  or  conscience,  as  soon  as  its  intellectual  powers 
had  become  as  well,  or  nearly  as  well  developed,  as  in  man. 
For,  firstly,  the  social  instincts  lead  an  animal  to  take 
pleasure  in  the  society  of  its  fellows,  to  feel  a  certain 
amount  of  sympathy  with  them,  and  to  perform  various 
services  for  them.  The  services  may  be  of  a  definite  and 
evidently  instinctive  nature  ;  or  there  may  be  only  a  wish 

*Mr.  Bain  gives  a  list("  Mental  and  Moral  Science,"  1868,  pp.  543- 
725)  of  twenty-six  British  authors  who  have  written  on  this  subject, 
and  whose  names  are  familiar  to  every  reader;  to  these,  Mr.  Bain's 
own  name,  and  those  of  Mr.  Lecky,  Mr.  Shadworth  Hodgson,  Sir  J. 
Lubbock  and  others,  might  be  added. 

f  Sir  B.  Brodie,  after  observing  that  man  is  a  social  animal  (•'  Psy- 
chological Enquiries,"  1854,  p.  192),  asks  the  pregnant  question, 
"ought  not  this  to  settle  the  disputed  question  as  to  the  existence  of 
a  moral  sense?"  Similar  ideas  have  probably  occurred  to  many  per- 
sons, as  they  did  long  ago  to  Marcus  Aurelius.  Mr.  J.  S.  Mill 
speaks,  in  his  celebrated  work,  '•Utilitarianism,"  (1864,  pp.  45,  46), 
of  the  social  feelings  as  a  "  powerful  natural  sentiment,"  and  as  "  the 
natural  basis  of  sentiment  for  utilitarian  morality."  Again  he  says, 
"  Like  the  other  acquired  capacities  above  referred  to,  the  moral 
faculty,  if  not  a  part  of  our  nature,  is  a  natural  outgrowth  from  it; 
capable,  like  them,  in  a  certain  small  degree  of  springing  up  sponta- 
neously." But  in  opposition  to  all  this,  he  also  remarks,  "if,  as  is 
my  own  Delief,  the  moral  feelings  are  not  innate,  but  acquired,  they 
are  not  for  that  reason  less  natural."  It  is  with  hesitation  that  I 
venture  to  differ  at  all  from  so  profound  a  thinker,  but  it  can  hardly 
be  disputed  that  the  social  feelings  are  instinctive  or  innate  in  the 
lower  animals;  and  why  should  they  not  be  so  in  man?  Mr.  Bain 
(see,  for  instance,  "  The  Emotions  and  the  Will,"  1865,  p.  481)  and 
others  believe  that  the  moral  sense  is  acquired  by  each  individual 
during  his  lifetime.  On  the  general  theory  of  evolution  this  is  at 
least  extremely  improbable.  The  ignoring  of  all  transmitted  mental 
qualities  will,  as  it  seems  to  me,  be  hereafter  judged  as  a  most  serious 
blemish  in  the  works  of  Mr.  Mill. 


112  TtiE  DESCENT  OF  MAN. 

and  readiness,  as  with  most  of  the  higher  social  animals,  to 
aid  their  fellows  in  certain  general  ways.  But  these  feel- 
ings and  services  are  by  no  means  extended  to  all  the  indi- 
viduals of  the  same  species,  only  to  those  of  the  same  asso- 
ciation. Secondly,  as  soon  as  the  mental  faculties  had 
become  highly  developed,  images  of  all  past  actions  and 
motives  would  be  incessantly  passing  through  the  brain  of 
each  individual;  and  that  feeling  of  dissatisfaction,  or  even 
misery,  which  invariably  results,  as  we  shall  hereafter  see, 
from  any  unsatisfied  instinct,  would  arise,  as  often  as  it 
was  perceived  that  the  enduring  and  always  present  social 
instinct  had  yielded  to  some  other  instinct,  at  the  time 
stronger,  but  neither  enduring  in  its  nature,  nor  leaving 
behind  it  a  very  vivid  impression.  It  is  clear  that  many 
instinctive  desires,  such  as  that  of  hunger,  are  in  their 
nature  of  short  duration;  and  after  being  satisfied,  are  not 
readily  or  vividly  recalled.  Thirdly,  after  the  power  of 
language  had  been  acquired,  and  the  wishes  of  the  commu- 
nity could  be  expressed,  the  common  opinion  how  each 
member  ought  to  act  for  the  public  good,  would  naturally 
become  in  a  paramount  degree  the  guide  to  action.  But  it 
should  be  borne  in  mind  that  however  great  weight  we  may 
attribute  to  public  opinion,  our  regard  for  the  approbation 
and  disapprobation  of  our  fellows  depends  on  sympathy, 
which,  as  we  shall  see,  forms  an  essential  part  of  the  social 
instinct,  and  is  indeed  its  foundation-stone.  Lastly,  habit 
in  the  individual  would  ultimately  play  a  very  important 
part  in  guiding  the  conduct  of  each  member;  for  the  social 
instinct,  together  with  sympathy,  is,  like  any  other  instinct, 
greatly  strengthened  by  habit,  and  so  consequently  would 
be  obedience  to  the  wishes  and  judgment  of  the  community. 
These  several  subordinate  propositions  must  now  be  discussed, 
and  some  of  them  at  considerable  length. 

It  may  be  well  first  to  premise  that  I  do  not  wish  to 
maintain  that  any  strictly  social  animal,  if  its  intellectual 
faculties  were  to  become  as  active  and  as  highly  developed 
as  in  man,  would  acquire  exactly  the  same  moral  sense  as 
ours.  In  the  same  manner  as  various  animals  have  some 
sense  of  beauty,  though  they  admire  widely  different 
objects,  so  they  might  have  a  sense  of  right  and  wrong, 
I  though  led  by  it  to  follow  widely  different  lines  of  conduct. 
If,  for  instance,  to  take  an  extreme  case,  men_vv^rercarcd 
underjrecisely  the  same  .conditions  asJiive;;bees7"tlTerc  can 


MORAL  SENSE.  113 

hardly  be  a  doubt  that  our  unmarried  females  would,  like 
the  worker- beee^  think  it  a  sacred  duty  to  kill  their 
brothers,  and  mothers  would  strive  to  Kill  their  fertile 
daughters;  and  no  one  would  think  of  interfering.*  Never- 
theless, the  bee,  or  any  other  social  animal,  would  gain  in 
our  supposed  case,  as  it  appears  to  me,  some  feeling  of 
right  or  wrong,  or  a  conscience.  For  each  individual 
would  have  an  inward  sense  of  possessing  certain  stronger 
or  more  enduring  instincts,  and  others  less  strong  or 
enduring;  so  that  there  would  often  be  a  struggle  as  to 
which  impulse  should  be  followed  ^  and  satisfaction,  dissat- 
isfaction, or  even  misery  would  be  felt,  as  past  impressions 
were  compared  during  their  incessant  passage  through  the 
mind.  In  this  case  an  inward  monitor  v/ould  tell  the 
animal  that  it  w^ould  have  been  better  to  have  followed  the 
one  impulse  rather  than  the  other.  The  one  course  ought 
to  have  been  followed,  and  the  other  ought  not;  the  one 
would  have  been  right  and  the  other  wrong;  but  to  these 
terms  I  shall  recur. 

Sociability. — Animals  of  many  kinds  are  social;  we  find 
even  distinct  species  living  together;  for  example,  some 
American  monkeys;  and  united  flocks  of  rooks,  jackdaws 
and  starlings.  Man  shows  the  same  feeling  in  his  strong 
love  for  the  dog,  which  the  dog  returns  with  interest.  Every 
one  must  have  noticed  how  miserable  horses,  dogs,  sheep, 
etc.,  are  when  separated  from  their  companions,  and  what 

*  Mr.  H.  Sidgwick  remarks,  in  an  able  discussion  on  this  subject 
(the  "  Academy,"  June  15,  1872,  p.  231),  "a  superior  bee,  we  may 
feel  sure,  would  aspire  to  a  milder  solution  of  the  population  ques- 
tion." Judging,  however,  from  the  habits  of  many  or  most  savages, 
man  solves  the  problem  by  female  infanticide,  polyandry  and  pro- 
miscuous intercourse,  therefore  it  may  well  be  doubted  whether  it 
would  be  by  a  milder  method.  MissCobbe,  in  commenting  ("  Darwin- 
ism in  Morals,"  ''Theological  Review,"  April,  1872,  pp.  188-191)  on 
the  same  illustration,  says,  the  principles  of  social  duty  would  be 
thus  reversed;  and  by  this,  I  presume,  she  means  that  the  fulfill 
ment  of  a  social  duty  would  tend  to  the  injury  of  individuals,  but 
she  overlooks  the  fact,  which  she  would  doubtless  admit,  that  the 
instincts  of  the  bee  have  been  acquired  for  the  good  3f  ths  commu- 
nity She  goes  so  far  as  to  say  that  if  the  theory  of  ethics  advocated 
in  this  chapter  were  ever  generally  accepted,  '■  I  cannot  but  believe 
that  in  the  hour  of  their  triumph  would  be  sounded  the  knell  of  the 
virtue  of  mankind."  It  is  to  be  hoped  that  the  belief  in  the  perma- 
nence of  virtue  on  this  earth  is  not  held  by  many  persons  on  so  weak 
a  tenure. 


114  THE  DESCENT  OF  MAN, 

strong  mutual  affection  the  two  former  kinds,  at  least, 
show  on  their  reunion.  It  is  curious  to  speculate  on  the 
feelings  of  a  dog,  who  will  rest  peacefully  for  hours  in  a 
room  with  his  master  or  any  of  the  family,  without  the  least 
notice  being  taken  of  him;  but  if  left  for  a  short  time  by 
himself,  barks  or  howls  dismally.  We  will  confine  our  at- 
tention to  the  higher  social  animals,  and  pass  over  insects, 
although  some  of  these  are  social,  and  aid  one  another  in 
many  important  ways.  The  most  common  mutual  service 
in  the  higher  animals  is  to  warn  one  another  of  danger  by 
means  of  the  united  senses  of  all.  Every  sportsman  knows, 
as  Dr.  Jaeger  remarks,*  how  difficult  it  is  to  approach 
animals  in  a  herd  or  troop.  Wild  horses  and  cattle  do  not, 
I  believe,  make  any  danger-signal ;  but  the  attitude  of  any 
one  of  them  who  first  discovers  an  enemy,  warns  the  others. 
Rabbits  stamp  loudly  on  the  ground  with  their  hind  feet  as 
a  signal ;  sheep  and  chamois  do  the  same  with  their  fore 
feet,  uttering  likewise  a  whistle.  Many  birds  and  some 
mammals,  post  sentinels,  which  in  the  case  of  seals  are  saidf 

fenerally  to  be  the  females.  The  leader  of  a  troop  of  mon- 
eys acts  as  the  sentinel,  and  utters  cries  expressive  both  of 
danger  and  of  safety.  J;  Social  animals  perform  many  little 
services  for  each  other;  horses  nibble,  and  cows  lick  each 
other,  on  any  spot  which  itches;  monkeys  search  each  other 
for  external  parasites;  and  Brehm  states  that  after  a  troop 
of  the  Cercopithecus  griseo-viridis  has  rushed  through  a 
thorny  brake,  each  monkey  stretches  itself  on  a  branch, 
and  another  monkey  sitting  by,  ^'  conscientiously  "  examines 
its  fur,  and  extracts  every  thorn  or  burr. 

Animals  also  render  more  important  services  to  one 
another;  thus  wolves  and  some  other  beasts  of  prey  hunt  in 
packs,  and  aid  one  another  in  attacking  their  victims.  Peli- 
cans fish  in  concert.  The  Hamadryas  baboons  turn  over 
stones  to  find  insects,  etc. ,  and  when  they  come  to  a  large 
one,  as  many  as  can  stand  round,  turn  it  over  together  and 

*  "  Die  Darwin'sche  Tlieorie,"  s.  101. 

f  Mr.  R.  Brown  in  "Proc.  Zoolog.  Soc,"  1868,  p.  409. 

X  Brehm,  "  Thierleben,"  B.  i,  1864,  s.  52,  79.  For  the  case  of  the 
monkeys  extracting  thorns  from  each  other,  see  s.  54.  With  respect 
to  the  Hamadryas  turning  over  stones,  the  fact  is  given  (s.  76)  on  the 
evidence  of  Alvarez,  whose  observations  Brehm  thinks  quite  trust- 
worthy. For  the  cases  of  the  old  male  baboons  attacking  the  dogs, 
g^Q  s.  79;  and  with  respect  to  the  eagle,  s.  56. 


MORAL  SENSE.  115 

share  the  booty.  Social  animals  mutually  defend  each  other. 
Bull  bisons  in  North  America,  when  there  is  danger,  drive 
the  cows  and  calves  into  the  middle  of  the  herd,  while  they 
defend  the  outside.  I  shall  also  in  a  future  chapter  give  an 
account  of  two  young  wild  bulls  at  Chillingham  attacking 
an  old  one  in  concert,  and  of  two  stallions  together  trying 
to  drive  away  a  third  stallion  from  a  troop  of  mares.  In 
Abyssinia,  Brehm  encountered  a  great  troop  of  baboons 
who  were  crossing  a  valley  ;  some  had  already  ascended 
che  opposite  mountain,  and  some  were  still  in  the  valley; 
the  latter  were  attacked  by  the  dogs,  but  the  old  males  im- 
mediately hurried  down  from  the  rocks,  and  with  mouths 
widely  opened,  roared  so  fearfully  that  the  dogs  quickly 
drew  back.  They  were  again  encouraged  to  the  attack;  but 
by  this  time  all  the  baboons  had  reascended  the  heights, 
excepting  a  young  one  about  six  months  old,  who,  loudly 
calling  for  aid,  climbed  on  a  block  of  rock  and  was  sur- 
rounded. Now  one  of  the  largest  males,  a  true  hero,  came 
down  again  from  the  mountain,  slowly  went  to  the  young 
one,  coaxed  him,  and  triumphantly  led  him  away — the  dogs 
being  too  much  astonished  to  make  an  attack.  I  cannot 
resist  giving  another  scene  which  was  witnessed  by  this 
same  naturalist ;  an  eagle  seized  a  young  Cercopithecus, 
which,  by  clinging  to  a  branch,  was  not  at  once  carried  off; 
it  cried  loudly  for  assistance,  upon  which  the  other  mem- 
bers of  the  troop,  with  much  uproar,  rushed  to  the  rescue, 
surrounded  the  eagle,  and  puUed  out  so  many  feathers  that 
he  no  longer  thought  of  his  prey,  but  only  how  to  escape. 
This  eagle,  as  Brehm  remarks,  assuredly  would  never  again 
attack  a  single  monkey  of  a  troop.* 

It  is  certain  that  associated  animals  have  a  feeling  of  love 
for  each  other  which  is  not  felt  by  non-social  adult  animals. 
How  far  in  most  cases  they  actually  sympathize  in  the  pains 
and  pleasures  of  others  is  more  doubtful,  especially  with 
respect  to  pleasures.  Mr.  Buxton,  however,  who  had  excel- 
lent means  of  observation^  states  that  his  macaws,  which 

*  Mr.  Belt  gives  the  case  of  a  spider-monkey  (Ateles)  in  Nicaragua, 
which  was  heard  screaming  for  nearly  two  hours  in  the  forest,  and 
was  found  with  an  eagle  perched  close  by  it.  The  bird  apparently 
feared  to  attack  as  long  as  it  remained  face  to  face;  and  Mr.  Belt  be- 
lieves, from  what  he  has  seen  of  the  habits  of  these  monkeys,  that 
they  protect  themselves  from  eagles  by  keeping  two  or  three 
together.     "The  Naturalist  in  Nicaragua,"  1874,  p.  118. 

\  '•  Annals  of  Mag.  of  Nat.  Hist.,"  Nov.,  1868,  p.  382. 


116  THE  DESCENT  OF  MAN. 

lived  free  in  Norfolk,  took  "  an  extravagant  interest "  in  a 
pair  with  a  nest;  and  whenever  the  female  left  it  she  was 
surrounded  by  a  troop  ^'  screaming  horrible  acclamations  in 
her  honor/^  It  is  often  difficult  to  judge  whether  animals 
have  any  feeling  for  the  sufferings  of  others  of  their  kind. 
Who  can  say  what  cows  feel  when  they  surround  and  stare 
intently  on  a  dying  or  dead  companion;  apparently,  how- 
ever, as  Houzeau  remarks,  they  feel  no  pity.  That  animals 
sometimes  are  far  from  feeling  any  sympathy  is  too  certain; 
for  they  will  expel  a  wounded  animal  from  the  herd,  or 
gore  or  worry  it  to  death.  This  is  almost  the  blackest  fact 
in  natural  history,  unless,  indeed,  the  explanation  which 
has  been  suggested  is  true,  that  their  instinct  or  reason 
leads  them  to  expel  an  injured  companion,  lest  beasts  of 
prey,  including  man,  should  be  tempted  to  follow  the  troop. 
In  this  case  their  conduct  is  not  much  worse  than  that  of 
the  North  American  Indians,  who  leave  their  feeble  com- 
rades to  perish  on  the  plains;  or  the  Fijians,  who,  when 
their  parents  get  old,  or  fall  ill,  bury  them  alive.  * 

Many  animals,  however,  certainly  sympathize  with  each 
other's  distress  or  danger.  This  is  the  case  even  with  birds. 
Capt.  Stansburyf  found  on  a  salt  lake  in  Utah  an  old 
and  completely  blind  pelican,  which  was  very  fat,  and 
must  have  been  well  fed  for  a  long  time  by  his  companions. 
Mr.  Blyth,  as  he  informs  me,  saw  Indian  crows  feeding  two 
or  three  of  their  companions  which  were  blind;  and  I  have 
heard  of  an  analogous  case  with  the  domestic  cock.  We 
may,  if  we  choose,  call  these  actions  instinctive;  but  such 
cases  are  much  too  rare  for  the  development  of  any  special 
instinct.  J  I  have  myself  seen  a  dog,  who  never  passed 
a  cat  who  lay  sick  in  a  basket,  and  was  a  great  friend  of  his, 
without  giving  her  a  few  licks  with  his  tongue,  the  surest 
sign  of  kind  feeling  in  a  dog. 

It  must  be  called  sympathy  that  leads  a  courageous  dog 
to  fly  at  any  one  who  strikes  his  master,  as  he  certainly  will. 

*  Sir  J.  Lubbock,  *' Prehistoric  Times,"  2d  edit.,  p.  446, 
f  As  quoted  by  Mr.  L.  H.  Morgan,  The  American  Beaver,"  1868, 
p.  272.  Capt.  Stansbury  also  gives  an  interesting  account  of  the 
manner  in  which  a  very  young  pelican,  carried  away  by  a  strong 
stream,  was  guided  and  encouraged  in  its  attemps  to  reach  the  shore 
by  half  a  dozen  old  birds. 

}  As  Mr.  Bain  states,  "effective  aid  to  a  sufferer  springs  from 
sympathy  proper."  "  Mental  and  Moral  Science,"  1868,  p.  245. 


MOHAL  S^NSB!.  117 

I  saw  a  person  pretending  to  beat  a  lady,  who  had  a  very 
timid  little  dog  on  her  lap,  and  the  trial  had  never  been 
made  before;  the  little  creature  instantly  jumped  away,  but 
after  the  pretended  beating  was  over,  it  was  really  pathetic 
to  see  how  perseveringly  he  tried  to  lick  his  mistress'  faoe, 
and  comfort  her.  Brehm  *  states  that  when  a  baboon  in 
confinement  was  pursued  to  be  punished,  the  others  tried 
to  protect  him.  It  must  have  been  sympathy  in  the  cases 
above  given  which  led  the  baboons  and  Cercopitheci  to 
defend  their  young  comrades  from  the  dogs  and  the  eagle. 
I  will  give  only  one  other  instance  of  sympathetic  and 
heroic  conduct,  in  the  case  of  a  little  American  monkey. 
Several  years  ago  a  keeper  at  the  Zoological  Gardens  showed 
me  some  deep  and  scarcely  healed  wounds  on  the  nape 
of  his  own  neck,  inflicted  on  him,  while  kneeling  on  the 
floor,  by  a  fierce  baboon.  The  little  American  monkey, 
who  was  a  warm  friend  of  this  keeper,  lived  in  the  same 
large  compartment,  and  was  dreadfull}'  afraid  of  the  great 
baboon.  Nevertheless,  as  soon  as  he  saw  his  friend  in 
peril,  he  rushed  to  the  rescue,  and  by  screams  and  bites  so 
distracted  the  baboon  that  the  man  was  able  to  escape, 
after,  as  the  surgeon  thought,  running  great  risk  of  his 
life. 

Besides  love  and  sympathy,  animals  exhibit  other  quali- 
ties connected  with  the  social  instincts,  which  in  us  would 
be  called  moral;  and  I  agree  with  Agassiz  \  that  dogs 
possess  something  very  like  a  conscience. 

Dogs  possess  some  power  of  self-command,  and  this  does 
not  appear  to  be  wholly  the  result  of  fear.  As  Braubach  J 
remarks,  they  will  refrain  from  stealing  food  in  the  absence 
of  their  master.  They  have  long  been  accepted  as  the  very 
type  of  fidelity  and  obedience.  But  the  elephant  is  like- 
wise very  faithiul  to  his  driver  or  keeper,  and  probably  con- 
siders him  as  the  leader  of  the  herd.  Dr.  Hooker  informs  me 
that  an  elephant,  which  he  was  riding  in  India,  became  so 
deeply  bogged  that  he  remained  stuck  fast  until  the  next 
day,  when  he  was  extricated  by  men  with  ropes.  Under 
such  circumstances  elephants  will  seize  with  their  trunks 
any  object,  dead  or  alive,  to  place  under  their  knees,  to 

*'♦  Tbierleben,"  B.  i,  s.  85. 

f  "  De  I'Espece  et  de  la  Classe,"  1869,  p.  97. 

X  "  Die  Darwin'sche  Art-Lehre,"  1869,  s.  54. 


118  THE  DESOBNT  OF  MaK. 

prevent  their  sinking  deeper  in  tlie  mud;  and  the  driver 
was  dreadfully  afraid  lest  the  animal  should  have  seized 
Dr.  Hooker  and  crushed  him  to  death.  But  the  driver 
himself^  as  Dr.  Hooker  was  assured,  ran  no  risk.  This  for- 
bearance, under  an  emergency  so  dreadful  for  a  heavy 
animal,  is  a  wonderful  proof  of  noble  fidelity.* 

All  animals  living  in  a  body,  which  defend  themselves  or 
attack  their  enemies  in  concert,  must  indeed  be  in  some 
degree  faithful  to  one  another  ;  and  those  that  follow 
a  leader  must  be  in  some  degree  obedient.  When  the 
baboons  in  Abyssiniaf  plunder  a  garden,  they  silently  follow 
their  leader;  and  if  an  imprudent  young  animal  makes  a 
a  noise,  he  receives  a  slap  from  the  others  to  teach  him 
silence  and  obedience.  Mr.  Galton,  who  has  had  excellent 
opportunities  for  observing  the  half-wild  cattle  in  S.  Africa, 
says,  J  that  they  cannot  endure  even  a  momentary  separa- 
tion from  the  herd.  They  are  essentially  slavish,  and 
accept  the  common  determination,  seeking  no  better  lot 
than  to  be  led  by  any  one  ox  who  has  enough  self-reliance 
to  accept  the  position.  The  men  who  break  in  these  ani- 
mals for  harness,  watch  assiduously  for  those  who,  by  graz- 
ing apart,  show  a  self-reliant  disposition,  and  these  they 
train  as  fore  oxen.  Mr.  Galton  adds  that  such  animals  are 
rare  and  valuable;  and  if  many  were  born  they  would  soon 
be  eliminated,  as  lions  are  always  on  the  lookout  for  the 
individuals  which  wander  from  the  herd. 

With  respect  to  the  impulse  which  leads  certain  animals 
to  associate  together,  and  to  aid  one  another  in  many  ways, 
we  may  infer  that  in  most  cases  they  are  impelled  by  the 
same  sense  of  satisfaction  or  pleasure  which  they  experi- 
ence in  performing  other  instinctive  actions ;  or  by  the 
same  sense  of  dissatisfaction  as  when  other  instinctive 
actions  are  checked.  We  see  this  in  innumerable  instances 
and  it  is  illustrated  in  a  striking  manner  by  the  acquired 
instincts  of  our  domesticated  animals;  thus  a  young  shep- 
herd-dog delights  in  driving  and  running  round  a  flock  of 
sheep,  but  not  in  worrying  them  ;  a  young  fox-hound 
delights  in  hunting  a  fox,  while  some  other  kinds  of  dogs, 

*  See  also  Hooker's  "  Himalayan  Journals,"  vol.  ii,  1854,  p.  333. 
f  Brehm,  "  Thierleben,"  B.  i,  s.  76. 

:|:See  his  extremely  interesting  paper  on  "  Gregarioiisness  in  Cat- 
tle and  in  Man,"  "  Macmillan's  Mag.,"  Feb.,  1871,  p.  353. 


MORAL  SENSE,  119 

as  I  have  witnessed,  utterly  disregard  foxes.  What  a 
strong  feeling  of  inward  satisfaction  must  impel  a  bird  so 
full  of  activity,  to  brood  day  after  day  over  her  eggs. 
Migratory  birds  are  quite  miserable  if  stopped  from  migra- 
ting; perhaps  they  enjoy  starting  on  their  long  flight;  but 
it  is  hard  to  believe  that  the  poor  pinioned  goose,  described 
by  Audubon,  which  started  on  foot  at  the  proper  time  for 
its  journey  of  probably  more  than  a  thousand  miles,  could 
have  felt  any  joy  in  doing  so.  Some  instints  are  determined 
solely  by  painful  feelings,  as  by  fear,  which  leads  to  self- 
preservation,  and  is  in  some  cases  directed  toward  special 
enemies.  No  one,  I  presume,  can  analyze  the  sensations 
of  pleasure  or  pain.  In  many  instances,  however, 
it  is  probable  that  instincts  are  persistently  followed 
from  the  mere  force  of  inheritance,  without  the  stimulus 
of  either  pleasure  or  pain.  A  young  pointer,  when  it  first 
scents  game,  apparently  cannot  help  pointing.  A  squirrel 
in  a  cage  who  pats  the  nuts  which  it  cannot  eat,  as  if  to 
bury  them  in  the  ground,  can  hardly  be  thought  to  act 
thus,  either  from  pleasure  or  pain.  Hence  the  common 
assumption  that  men  must  be  impelled  to  every  action  by 
experiencing  some  pleasure  or  pain  may  be  erroneous. 
Although  a  habit  may  be  blindly  and  implicitly  followed, 
independently  of  any  pleasure  or  pain  felt  at  the  moment, 
yet  if  it  be  forcibly  and  abruptly  checked,  a  vague  sense  of 
dissatisfaction  is  generally  experienced. 

It  has  often  been  assumed  that  animals  were  in  the  first 
place  rendered  social,  and  that  they  feel  as  a  consequence 
uncomfortable  when  separated  from  each  other,  and  com- 
fortable while  together;  but  it  is  a  more  probable  view  that 
these  sensations  were  first  develoj^ed  in  order  that  those 
animals  which  would  profit  by  living  in  society  should  be 
induced  to  live  together,  in  the  same  manner  as  the  sense 
of  hunger  and  the  pleasure  of  eating  were,  no  doubt,  first 
acquired  in  order  to  induce  animals  to  eat.  The  feeling  of 
pleasure  from  society  is  probably  an  extension  of  the 
parental  or  filial  affections,  since  the  social  instinct  seems 
to  be  developed  by  the  young  remaining  for  a  long  time 
with  their  parents;  and  this  extension  may  be  attributed  in 
part  to  habit,  but  chiefly  to  natural  selection.  AVith  those 
animals  which  were  benefited  by  living  in  close  association, 
tlie  individuals  which  took  the  great^^-st  pleasure  in  society 
would  best  escape  various  dangers,  while  those  that  cared 


120  THE  DESCENT  OF  MAN. 

least  for  their  comrades,  and  lived  solitary,  would  perish  in 
greater  numbers.  With  respect  to  the  origin  of  the  parental 
and  filial  affections,  which  apparently  lie  at  the  base  of  the 
social  instincts,  we  know  not  the  steps  by  which  they  have 
been  gained;  but  we  may  infer  that  it  has  been  to  a  large 
extent  through  natural  selection.  So  it  has  almost  cer- 
tainly been  with  the  unusual  and  opposite  feeling  of  hatred 
between  the  nearest  relations,  as  with  the  worker-bees 
which  kill  their  brother  drones,  and  with  the  queen  bees 
which  kill  their  daughter  queens;  the  desire  to  destroy 
their  nearest  relations  having  been  in  this  case  of  service  to 
the  community.  Parental  affection,  or  some  feeling  which 
replaces  it,  has  been  developed  in  certain  animals  extremely 
low  in  the  scale,  for  example,  in  star-fishes  and  spiders. 
It  is  also  occasionally  present  in  a  few  members  alone  in  a 
whole  group  of  animals,  as  in  the  genus  Forficula,  or 
earwigs. 

The  all-important  emotion  of  sympathy  is  distinct  from 
that  of  love.  A  mother  may  passionately  love  her  sleep- 
ing and  passive  infant,  but  she  can  hardly  at  such  times 
be  said  to  feel  sympathy  for  it.  The  love  of  a  man  for 
his  dog  is  distinct  from  sympathy,  and  so  is  that  of  a  dog 
for  his  master.  Adam  Smith  formerly  argued,  as  has 
Mr.  Bain  recently,  that  the  basis  of  sympathy  lies  in  our 
strong  retentiveness  of  former  states  of  pain  or  pleasure. 
Hence,  ^'^the  sight  of  another  person  enduring  hunger, 
cold,  fatigue,  revives  in  us  some  recollection  of  the 
states,  which  are  painful  even  in  idea.''^  We  are  thus 
impelled  to  relieve  the  sufferings  of  another  in  order  that 
our  own  painful  feelings  may  be  at  the  same  time  relieved. 
In  like  manner  we  are  led  to  participate  in  the  pleasures  of 
others.*  But  I  cannot  see  how  this  view  explains  the  fact 
that  sympathy  is  excited,  in  an  immeasurably  stronger 
degree,    by  a    beloved,   than    by   an    indifferent    person. 

*  See  the  first  and  striking  chapter  in  Adam  Smith's  "  Theory  of 
Moral  Sentiments."  Also  Mr.  Bain's  "Mental  and  Moral  Science," 
1868,  pp.  244  and  275-282.  Mr.  Bain  states,  that  "  sympathy  is,  in- 
directly, a  source  of  pleasure  to  the  sympathizer;"  and  he  accounts 
for  this  through  reciprocity.  He  remarks  that  "the  person  bene- 
fited, or  others  in  his  stead,  may  make  up,  by  sympathy  and  good 
offices  returned,  for  all  the  sacrifice."  But  if,  as  appears  to  be  the 
case,  sympathy  is  strictly  an  instinct,  its  exercise  would  give  direct 
pleasure,  in  the  same  manner  as  the  exercise,  as  before  remarked,  of 
almost  every  other  instinct. 


MORAL  SENSE.  121 

The  mere  sight  of  suffering,  independently  of  love,  would 
suffice  to  call  up  in  us  vivid  recollections  and  associations. 
The  explanation  may  lie  in  the  fact  that,  with  all  animals, 
sympathy  is  directed  solely  toward  the  members  of  the  same 
community,  and  therefore  toward  known  and  more  or  less 
beloved  members,  but  not  to  all  the  individuals  of  the  same 
species.  This  fact  is  not  more  surprising  than  that  the 
fears  of  many  animals  should  be  directed  against  special 
enemies.  Species  which  are  not  social,  such  as  lions  and 
tigers,  no  doubt  feel  sympathy  for  the  suffering  of  their  own 
young,  but  not  for  that  of  any  other  animal.  With  man- 
kind selfishness,  experience,  and  imitation,  probably  add, 
as  Mr.  Bain  has  shown,  to  the  power  of  sympathy;  for  we 
are  led  by  the  hope  of  receiving  good  in  return  to  perform 
acts  of  sympathetic  kindness  to  others;  and  sympathy  is 
much  strengthened  by  habit.  In  however  complex  a 
manner  this  feeling  may  have  originated,  as  it  is  one  of  high 
importance  to  all  those  animals  which  aid  and  defend  one 
another,  it  will  have  been  increased  through  natural  selec- 
tion; for  those  communities,  which  included  the  greatest 
number  of  the  most  sympathetic  members,  would  flourish 
best  and  rear  the  greatest  number  of  offspring. 

It  is,  however,  impossible  to  decide  in  many  cases  whether 
certain  social  instincts  have  been  acquired  through  natural 
selection,  or  are  the  indirect  result  of  other  instincts  and 
faculties,  such  as  sympathy,  reason,  experience,  and  a  ten- 
dency to  imitation;  or  again,  whether  they  are  simply  the 
result  of  long-continued  habit.  So  remarkable  an  instinct 
as  the  placing  sentinels  to  warn  the  community  of  danger 
can  hardly  have  been  the  indirect  result  of  any  of  these 
faculties;  it  must,  therefore,  have  been  directly  acquired. 
On  the  other  hand,  the  habit  followed  by  the  males  of  some  \ 
social  animals  of  defending  the  community,  and  of  attack-  » 
ing  their  enemies  or  their  prey  in  concert,  may  perhaps 
have  originated  from  mutual  sympathy;  but  courage,  and 
in  most  cases  strength,  must  have  been  previously  acquired, 
probably  through  natural  selection. 

Of  the  various  instincts  and  habits,  some  are  much 
stronger  than  others;  that  is,  some  either  give  more  pleas- 
ure in  their  performance,  and  more  distress  in  their  pre- 
vention, than  others;  or,  which  is  probably  quite  as  impor- 
tant, they  are,  through  inheritance,  more  persistently 
followed,  without  exciting  any  special  feeling  of  pleasure 


122  THE  DESCENT  OF  MAK. 

or  pain.  We  are  ourselves  conscious  that  some  habits  ar<3 
much  more  difficult  to  cure  or  change  than  others.  Hence 
a  struggle  may  often  be  observed  in  animals  between  dif- 
ferent instincts,  or  between  an  instinct  and  some  habitual 
disposition;  as  when  a  dog  rushes  after  a  hare,  is  rebuked, 
pauses,  hesitates,  pursues  again,  or  returns  ashamed  to  his 
master;  or  as  between  the  love  of  a  female  dog  for  her 
young  puppies  and  for  her  master — for  she  may  be  seen  to 
slink  away  to  them  as  if  half -ashamed  of  not  accompanying 
her  master.  But  the  most  curious  instance  known  to  me  of 
one  instinct  getting  the  better  of  another,  is  the  migratory 
instinct  conquering  the  maternal  instinct.  The  former  is 
wonderfully  strong ;  a  confined  bird  will  at  the  proper 
season  beat  her  breast  against  the  wires  of  her  t  .ge  until 
it  is  bare  and  bloody.  It  causes  young  salmon  to  leap  out 
of  the  fresh  water,  in  which  they  could  continue  to  exist, 
and  thus  unintentionally  to  commit  suicide.  Every  one 
knows  how  strong  the  maternal  instinct  is,  leading  even 
timid  birds  to  face  great  danger,  though  with  hesitation, 
and  in  opposition  to  the  instinct  of  self-preservation. 
Nevertheless,  the  migratory  instinct  is  so  powerful  that 
late  in  the  autumn  swallows,  house-martins,  and  swifts  fre- 
quently desert  their  tender  young,  leaving  them  to  perish 
(miserably  in  their  nests.* 
We  can  perceive  that  an  instinctive  impulse,  if  it  be  in 
ally  way  more  beneficial  to  a  species  than  some  other  or 
opposed  instinct,  would  be  rendered  the  more  potent  of  the 
two  through  natural  selection;  for  the  individuals  which 
had  it  most  strongly  developed  would  survive  in  larger  num- 
bers. Whether  this  is  the  case  with  the  migratory  in  com- 
parison with  the  maternal  instinct,  may  be  doubted.     The 


*  This  fact,  the  Rev.  L.  Jenyns  states  (see  his  edition  of  "  White's 
Nat.  Hist,  of  Selborne,"  1853,  p.  204)  was  first  recorded  by  the  illus- 
trious Jenner,  in  "  Phil .  Transact. , "  1824,  and  has  since  been  confirmed 
by  several  observers,  especially  by  Mr.  Black  wall.  This  latter  care- 
ful observer  examined,  late  in  the  autumn,  during  two  years,  thirty- 
six  nests;  he  found  that  twelve  contained  young  dead  birds,  five  con- 
tained eggs  on  the  point  of  being  hatched,  and  three,  eggs  not  nearly 
hatched.  Many  birds,  not  yet  old  enough  for  a  prolonged  flight,  are 
likewise  deserted  and  left  behind.  See  Blackwall,  "  Researches  in 
Zoology,"  1834,  pp.  108,  118.  For  some  additional  evidence,  although 
this  is  not  wanted,  see  Leroy,  "  Lett  res  Phil.,"  1802,  p.  217.  For 
swifts,  Gould's  "Introduction  to  the  Birds  of  Great  Britain,"  1823, 
p.  5.  Similar  cases  have  been  observed  in  Canada  by  Mr.  A-<apis; 
"Pop.  Science  Review,"  July.  1873,  p.  283. 


MonAL  8ENSK  l^g 

great  persistence  or  steady  action  of  the  former  at  certain 
seasons  of  the  year  during  the  whole  day,  may  give  it  for  a 
time  paramount  force. 

Ma7l  a  Social  Animah — ViVPry  hn4  will  arlTn^j^  f||^|  njt^ji  is 

a  social  being.  We  see  this  in  his  dislike  of  solitude,  and 
in  his^Wtsli  for  society  beyond  that  of  his  own  family. 
Solitary  confinement  is  one  of  the  severest  punishments 
which  can  be  inflicted.  Some  authors  suppose  that  man 
prime vally  lived  in  single  families;  but  at  the  present  day, 
though  single  families,  or  only  two  or  three  together,  roam 
the  solitudes  of  some  savage  lands,  they  always,  as  far  as  I 
can  discover,  hold  friendly  relations  with  other  families 
inhabiting  the  same  district.  Such  families  occasionally 
meet  in  council,  and  unite  for  their  common  defense.  It 
is  no  argument  against  savage  man  being  a  social  animal, 
that  the  tribes  inhabiting  adjacent  districts  are  almost 
always  at  war  with  each  other;  for  the  social  instincts  never 
extend  to  all  the  individuals  of  th6  same  species.  Judging 
from  the  analogy  of  the  majority  of  the  Quadrumana,  it  m 
probable  that  the  early  ape-like  progenitors  of  man  were 
likewise  social ;  but  this  is  not  of  much  importance  for  usJ 
Although  man,  as  he  now  exists,  has  few  special  instincts, 
having  lost  any  which  his  early  progenitors  may  have 
^possessed,  this  is  no  reason  why  he  should  not  have  retained 
I  from  an  extremely  remote  period  some  degree  of  instinctive 
I  love  and  sympathy  for  his  fellows.  We  are  indeed  all  con- 
^  scions  that  we  do  possess  such  sympathetic  feelings;*  but 
our  consciousness  does  not  tell  us  whether  they  are  instinct- 
ive, having  originated  long  ago  in  the  same  manner 
as  with  the  lower  animals,  or  whether  they  have  been 
acquired  by  each  of  us  during  our  early  years.  As  man  is 
a  social  animal,  it  is  almost  certain  that  he  would  inherit  a 
tendency  to  be  faithful  to  his  comrades  and  obedient  to 
the  leader  of  his  tribe;  for  these  qualities  are  common  to 
most  social  animals.  He  would  consequently  possess  some 
capacity  for  self-command.     He  would  from  an  inherited 

♦Hume  remarks  ("An  Enquiry  Concerning  the  Principles  of 
Morals,"  edit,  of  1751,  p.  132),  "There  seems  a  necessity  for  con- 
fessing that  the  happiness  and  misery  of  others  are  not  spectacles 
altogether  indifferent  to  us,  but  that  the  view  of  the  former  .  .  . 
communicates  a  secret  joy;  the  appearance  of  the  latter  ,  .  , 
throws  a  melancholy  damp  over  the  imagination." 


124  THE  DESCENT  OF  MAN. 

tendency  be  willing  to  defend,  in  concert  with  others^  his 
fellow-men;  and  would  be  ready  to  aid  them  in  any  way, 
which  did  not  too  greatly  interfere  with  his  own  welfare  or 
his  own  strong  desires. 

The  social  animals  which  stand  at  the  bottom  of  the  scale 
are  guided  almost  exclusively,  and  those  which  stand  higher 
in  the  scale  are  largely  guided,  by  special  instincts  in  the 
aid  which  they  give  to  the  members  of  the  same  commu- 
nity; but  they  are  likewise  in  part  impelled  by  mutual  love 
and  sympathy,  assisted  apparently  by  some  amount  of 
reason.  Although  man,  as  just  remarked,  has  no  special 
instincts  to  tell  him  how  to  aid  his  fellow-men,  he  still  has 
the  impulse,  and  with  his  improved  intellectual  faculties 
would  naturally  be  much  guided  in  this  respect  by  reason 
and  experience.  Instinctive  sympathy  would  also  cause 
him  to  value  highly  the  approbation  of  his  fellows;  for,  as 
Mr.  Bain  has  clearly  shown,*  the  love  of  praise  and  the 
strong  feeling  of  glory,  and  the  still  stronger  horror  of 
scorn  and  infamy,  "are  due  to  the  workings  of  sympathy.^' 
Consequently  man  would  be  influenced  in  the  highest 
degree  by  the  wishes,  approbation,  and  blame  of  his  fellpw- 
men,  as  expressed  by  their  gestures  and  language.  Thus 
the  social  instincts,  which  must  have  been  acquired  by  man 
in  a  very  rude  state,  and  probably  even  by  his  early  ape-like 
progenitors,  still  give  the  impulse  to  some  of  his  best 
actions;  but  his  actions  are  in  a  higher  degree  determined 
by  the  expressed  wishes  and  judgment  of  his  fellow-men, 
and  unfortunately  very  often  by  his  own  strong  selfish 
desires.  But  as  love,  sympathy  and  self-command  become 
strengthened  by  habit,  and  as  the  power  of  reasoning 
becomes  clearer,  so  that  man  can  value  justly  the  judgments 
of  his  fellows,  he  will  feel  himself  impelled,  apart  from 
any  transitory  pleasure  or  pain,  to  certain  lines  of  conduct. 
He  might  then  declare — not  that  any  barbarian  or  unculti- 
vated man  could  thus  think — I  am  the  supreme  judge  of 
my  own  conduct,  and  in  the  words  of  Kant,  I  will  not  in 
my  own  person  violate  the  dignity  of  humanity. 

The  More  Enduring  Social  Instincts  Conquer  the  Less  Per- 
sistent Instincts. — We  have  not,  however,  as  yet  considered 
the  main  point,  on  which,  from  our  present  point  of  view, 

*  "  Mental  and  Moral  Science,"  1868,  p.  354. 


MORAL  SENSE.  125 

the  whole  question  of  the  moral  sense  turns.  Why  should 
a  man  feel  that  he  ought  to  obey  one  instinctive  desire 
rather  than  another?  Why  is  he  bitterly  regretful,  if  he 
has  yielded  to  a  strong  sense  of  self-preservation,  and  has 
not  risked  his  life  to  save  that  of  a  fellow-creature?  or  why 
does  he  regret  having  stolen  food  from  hunger? 

It  is  evident,  in  the  first  place,  that  with  mankind  the 
instinctive  impulses  have  different  degrees  of  strength;  a 
savage  will  risk  his  own  life  to  save  that  of  a  member  of 
the  same  community,  but  will  be  wholly  indifferent  about 
a  stranger  ;  a  young  and  timid  mother  urged  by  the 
maternal  instinct  will,  without  a  moment's  hesitation, 
run  the  greatest  danger  for  her  own  infant,  but  not  for 
a  mere  fellow-creature.  Nevertheless  many  a  civilized  man, 
or  even  boy,  who  never  before  risked  his  life  for  another, 
but  full  of  courage  and  sympathy,  has  disregarded  the 
instinct  of  self-preservation,  and  plunged  at  once  into  a 
torrent  to  save  a  drowning  man,  though  a  stranger.  In 
this  case  man  is  impelled  by  the  same  instinctive  motive 
which  made  the  heroic  little  American  monkey,  fomerly 
described,  save  his  keeper,  by  attacking  the  great  and 
dreaded  baboon.  Such  actions  as  the  above  appear  to  be 
the  simple  result  of  the  greater  strength  of  the  social  or 
maternal  instincts  than  that  of  any  other  instinct  or  motive; 
for  they  are  performed  too  instantaneously  for  reflection, 
or  for  pleasure  or  pain  to  be  felt  at  the  time;  though,  if 
prevented  by  any  cause,  distress  or  even  misery  might  be 
felt.  In  a  timid  man,  on  the  other  hand,  the  instinct  of 
self-preservation  might  be  so  strong,  that  he  would  be 
unable  to  force  himself  to  run  any  such  risk,  perhaps  not 
even  for  his  own  child. 

I  am  aware  that  some  persons  maintain  that  actions  per^ 
formed  impulsively,  as  in  the  above  cases,  do  not  come 
under  the  dominion  of  the  moral  sense,  and  cannot  be 
called  moral.  They  confine  this  term  to  actions  done 
deliberately,  after  a  victory  over  opposing  desires,  or  when 
prompted  by  some  exalted  motive.  But  it  appears  scarcely 
possible  to  draw  any  cleaf  line  of  distinction  of  this  kind.* 

*  I  refer  here  to  tbe  distinction  between  what  has  been  called 
material  Siwdi  formal  raoTaWij .  I  am  glad  to  find  that  Prof.  Huxley 
("Critiques  and  Addresses,"  1873,  p.  287)  takes  the  same  view  on 
this  subject  as  I  do.  Mr.  Leslie  Stephen  remarks  ("  Essays  on  Free- 
thinking  and  Plain  Speaking,"  1873,  p.  83),  "the  metaphysical  dis- 
tinction, l>etween  material  and  formal  morality  is  as  irrevelant  as 
other  such  distinctions." 


126  THE  DESCENT  OF  MAN. 

As  far  as  exalted  motives  are  concerned,  many  instances 
have  been  recorded  of  savages,  destitute  of  any  feeling  of 
general  benevolence  toward  mankind,  and  not  guided  by 
any  religious  motive,  who  have  deliberately  sacrificed  their 
lives  as  prisoners,*  rather  than  betray  their  comrades;  and 
surely  their  conduct  ought  to  be  considered  as  moral.  As 
far  as  deliberation,  and  the  victory  over  opposing  motives 
are  concerned,  animals  may  be  seen  doubting  between 
opposed  instincts,  in  rescuing  their  offspring  or  comrades 
from  danger;  yet  their  actions,  though  done  for  the  good 
of  others,  are  not  called  moral.  Moreover,  anything  per- 
formed very  often  by  us,  will  at  last  be  done  without 
deliberation  or  hesitation,  and  can  then  hardly  be  distin- 
guished from  an  instinct;  yet  surely,  no  one  will  pretend 
that  such  an  action  ceases  to  be  moral.  On  the  contrary, 
we  all  feel  that  an  act  cannot  be  considered  as  perfect,  or 
as  performed  in  the  most  noble  manner,  unless  it  be  done 
impulsively,  without  deliberation  or  effort,  in  the  same 
manner  as  by  a  man  in  whom  the  requisite  qualities  are 
innate.  He  who  is  forced  to  overcome  his  fear  or  want  of 
sympathy  before  he  acts,  deserves,  however,  in  one  way 
higher  credit  than  the  man  whose  innate  disposition  leads 
him  to  a  good  act  without  effort.  As  we  cannot  distinguish 
between  motives,  we  rank  all  actions  of  a  certain  class  as 
moral,  if  performed  by  a  moral  being.  A  nioral  being  is 
one  who  is  capable  of  comparing  his  past  and.Iuture  actions 
or  motives,  and  of  approving  or  dis^proving  of  them.  We 
have  no  reason  to  suppose  that  ai!y  uX  "the  lower  animals 
have  this  capacity;  therefore,  when  a  Newfoundland  dog 
drags  a  child  out  of  the  water,  or  a  monkey  faces  danger  to 
rescue  its  comrade,  or  takes  charge  of  an  orphan  monkey, 
we  do  not  call  its  conduct  moral.  But  in  the  case  of  man, 
who  alone  can  with  certainty  be  ranked  as  a  moral  being, 
actions  of  a  certain  class  are  called  moral,  whether  per- 
formed deliberately,  after  a  struggle  with  ojiposing  motives, 
or  impulsively  through  instinct,  or  from  the  effects  of 
slowly  gained  habit. 

»  But  to  return  to  our  more  immediate  subject.  Although 
some  instincts  are  more  powerful  than  others,  and  thus  lead 
to  corresponding  actions,  yet  it  is  untenable,  that  in  man 


*  I  have  given  one  sucli  case,  namelv,  of  three  Patagonian  Indians 
who  preferred  being  shot,  one  after  the  other,  to  betraying  the  plans 
of  tb^ir  companions  in  war  ("  Journal  of  Researches,"  1845,  p-  1Q3), 


MORAL  SENSE.  127 

I  the  social  instincts  (including  the  love  of  praise  and  fear  oi 
I  blame)  possess  greater  strength,  or  have,  through  long^ 
/habit,  acquired  greater  strength  than  the  instincts  of  self 
/  preservation,  hunger,  lust,  vengeance,  etc.  Why  then  does 
'  man  regret,  even  though  trying  to  banish  such  regrets,  that 
he  has  followed  the  one  natural  impulse  rather  than  the 
other;  and  why  does  he  further  feel  that  he  ought  to  regret 
his  conduct?  Man  in  this  respect  differs  profoundly  from 
the  lower  animals.  Nevertheless  we  can,  I  think,  see  with 
some  degree  of  clearness  the  reason  of  this  difference. 
*  Man,  from  the  activity  of  his  mental  faculties,  cannot 
avoid  reflection;  past  impressions  and  images  are  incessantly 
and  clearly  passing  through  his  mind.  Now  with  those 
animals  which  live  permanently  in  a  body,  the  social 
instincts  are  ever  present  and  persistent.  Such  animals  are 
always  ready  to  utter  the  danger-signal,  to  defend  the  com- 
munity, and  to  give  aid  to  their  fellows  in  accordance  with 
their  habits;  they  feel  at  all  times,  without  the  stimulus  of 
any  special  passion  or  desire,  some  degree  of  love  and  sym- 
pathy for  them;  they  are  unhappy  if  long  separated  from 
them,  and  always  happy  to  be  again  in  their  company.  So 
it  is  with  ourselves.  Even  when  we  are  quite  alone,  how 
often  do  we  think  with  pleasure  or  pain  of  what  othere 
think  of  us — of  their  imagined  approbation  or  disapproba- 
tion; and  this  all  follows  from  sympathy,  a  fundamental 
element  of  the  social  instincts.  A  man  who  possessed  no 
trace  of  such  instincts  would  be  an  unnatural  monster.  On 
the  other  hand,  the  desire  to  satisfy  hunger,  or  any  passioi 
such  as  vengeance,  is  in  its  nature  temporary,  and  can  for 
time  be  fully  satisfied.  Nor  is  it  easy,  perhaps  hardly  pos-j 
sible,  to  call  up  wdth  complete  \dvidness  the  feeling,  foi 
instance,  of  hunger;  nor  indeed,  as  has  often  been  remarkec" 
of  any  suffering.  The  instinct  of  self-preservation  is  nc 
felt  except  in  the  presence  of  danger;  and  many  a  cowar( 
has  thought  himself  brave  until  he  has  met  his  enemy  fac^ 
to  face.  The  wisli  for  another  m^n's  property  is  perha2)d 
as  persistent  a  desire  as  any  that  can  be  named;  but  pven 
in  this  case  the  satisfaction  of  actual  possession  is  generally 
a  weaker  feeling  than  the  desire;  many  a  thief,  if  not  an 
habitual  one,  after  success  has  wondered  why  he  stole  some 
article. * 

*  Enmit;y  or  hatred  spems  also  to  be  a  higlily  persistent  feeling, 
perhaps  wore  so  fhw  Wi^  otUer  that  can  be  named,     Envy  is  define^ 


128  THE  DESCENT  OF  MA  N 

A  man  cannot  prevent  past  impressions  often  repassing 
tlirougli  his  mind;  he  will  thus  he  driven  to  make  a  com- 
parison between  the  impressions  of  past  hunger^  vengeance 
satisfied,  or  danger  shunned  at  other  men^s  cost,  with  the 
almost  ever-present  instinct  of  sympathy,  and  with  his 
early  knowledge  of  what  others  consider  as  praiseworthy  or 
hlameable.  This  knowledge  cannot  be  banished  from  his 
mind,  and  from  instinctive  sympathy  is  esteemed  of  great 
moment.  He  will  then  feel  as  if  he  had  been  balked  in 
following  a  present  instinct  or  habit,  and  this  with  all 
animals  causes  dissatisfaction,  or  even  misery. 

The  above  case  of  the  swallow  affords  an  illustration, 
though  of  a  reversed  nature,  of  a  temporary  though  for  the 
time  strongly  persistent  instinct  conquering  another  in- 
stinct, which  is  usually  dominant  over  all  others.  At  the 
proper  season  these  birds  seem  all  day  long  to  be  impressed 
with  the  desire  to  migrate  ;  their  habits  change  ;  they 
become  restless,  are  noisy  and  congregate  in  flocks.  While 
the  mother-bird  is  feeding,  or  brooding  over  her  nestlings, 
the  maternal  instinct  is  probably  stronger  than  the  migra- 
tory; but  the  instinct  which  is  the  more  persistent  gains 
the  victory,  and  at  last,  at  a  moment  when  her  young  ones 
are  not  in  sight,  she  takes  flight  and  deserts  them.  When 
arrived  at  the  end  of  her  long  journey,  and  the  migratory 
instinct  has  ceased  to  act,  what  an  agony  of  remorse  the 
bird  would  feel  if,  from  being  endowed  with  great  mental 

as  hatred  of  another  for  some  excellence  or  success;  and  Bacon  in- 
sists (Essay  ix),  **  Of  all  other  affections  envy  is  the  most  importune 
and  conthiual."  Dogs  are  very  apt  to  hate  both  strange  men  and 
strange  dogs,  especially  if  they  live  near  at  hand,  but  do  not  belong 
to  the  same  family,  tribe,  or  clan;  this  feeling  would  thus  seem  to  be 
innate,  and  is  certainly  a  most  persistent  one.  It  seems  to  be  the 
complement  and  converse  of  the  true  social  instinct.  From  what  we 
hear  of  savages,  it  would  appear  that  something  of  the  same  kind 
holds  good  with  them.  If  this  be  so,  it  would  be  a  small  step  in  any 
one  to  transfer  such  feelings  to  any  member  of  the  same  tribe  if  he 
had  done  him  an  injury  and  had  become  his  enemy.  Nor  is  it 
probable  that  the  primitive  conscience  would  reproach  a  man  for  in- 
juring his  enemy;  rather  it  would  reproach  him,  if  he  had  not 
revenged  himself.  To  do  good  in  return  for  evil,  to  love  your 
enemy,  is  a  height  of  morality  to  which  it  may  be  doubted  whether 
the  social  instincts  would,  by  themselves,  have  ever  led  us.  It  is 
necessary  that  these  instincts,  together  with  sympathy,  should  have 
been  highly  cultivated  and  extended  by  the  aid  ot  reason,  instruc- 
ti(m,  and  the  love  or  fear  of  God,  before  any  such  golden  rule  would 
ever  be  thought  of  and  obeyed. 


MORAL  SENSE.  129 

activity,  she  could  not  prevent  the  image  constantly  passing 
through  her  mind  of  her  young  ones  perishing  in  the  bleak 
north  from  cold  and  hunger. 

At  the  moment  of  action  man  will  no  doubt  be  apt  tq 
follow  the  stronger  impulse;  and  though  this  may  occa4 
sionally  prompt  him  to  the  noblest  deeds,  it  will  more  com4 
monly  lead  him  to  gratify  his  own  desires  at  the  expense  of 
other  men.  But  after  their  gratification,  when  past  and 
weaker  impressions  are  judged  by  the  ever-enduring  social 
instinct,  and  by  his  deep  regard  for  the  good  opinion  o^ 
his  fellows,  retribution  will  surely  come.  He  will  then 
feel  remoi*se,  repentance,  regret  or  shame;  this  latter  feel- 
ing, however,  relates  almost  exclusively  to  the  judgmer.t  of 
others.  He  will  consequently  resolve  more  or  less  firmly 
to  act  differently  for  the  future;  and  this  is  conscip.pcp!  for 
conscience  looks  backward  and  serves  as  a  guide  for  the 
future. 

The  nature  and  strength  of  the  feelings  which  we  call 
regret,  shame,  repentance  or  remorse,  depend  apparently 
not  only  on  the  strength  of  the  violated  instinct,  hy\t  paj-tly 
on  the  strength  of  the  temptation .  and  often  still  more  on 
the  j-^T^gmmt  nf  onr  fftHowR-  HoAV  far  each  man  values 
the  appreciation  of  others  depends  on  the  strength  of  his 
innate  or  acquired  feeling  of  sympathy;  and  on  his  own 
capacity  for  reasoning  out  the  remote  consequences  of  his 
acts.  Another  element  is  most  important,  although  not 
necessary,  the  reverence  or  fear  of  the  gods,  or  spirits 
believed  in  by  each  man;  and  this  applies  especially  in 
cases  of  remorse.  Several  critics  have  objected  that 
though  some  slight  regret  or  repentance  may  be  explained 
by  the  view  advocated  in  this  chapter,  it  is  impossible  thus 
to  account  for  the  soul-shaking  feeling  of  remorse.  But  I 
can  see  little  force  in  this  objection.  My  critics  do  not 
define  what  they  mean  by  remorse,  and  I  can  find  no  defi- 
nition implying  more  than  an  overwhelming  sense  of 
repentance.  Remorse  seems  to  bear  the  same  relation  to 
repentance,  as  rage  does  to  anger,  or  agony  to  pain.  It  is 
far  from  strange  that  an  instinct  so  strong  and  so  gener- 
ally admired,  as  maternal  love,  should,  if  disobeyed;  lead  to 
the  deepest  misery,  as  soon  as  the  impression  of  the  past 
cause  of  disobedience  is  weakened.  Even  when  an  action 
is  opposed  to  no  special  instinct,  merely  to  know  that  our 
f  j-iends  and  equals  despise  us  for  it,  is  enough  to  cause  great 


130  THE  DESCENT  OF  MAN. 

misery.  Who  can  doubt  that  the  refusal  to  figlit  a  duel 
through  fear  has  caused  many  men  an  agony  of  shame? 
Many  a  Hindoo,  it  is  said,  has  been  stirred  to  the  bottom 
of  his  soul  by  having  partaken  of  unclean  food.  Here  is 
another  case  of  what  must,  I  think,  be  called  remorse. 
Dr.  Landor  acted  as  a  magistrate  in  West  Australia,  and 
relates,*  that  a  native  on  his  farm,  after  losing  one  of  his 
wives  from  disease,  came  and  said  that  '^^  he  was  going  to 
a  distant  tribe  to  spear  a  woman,  to  satisfy  his  sense  of 
duty  to  his  wife.  I  told  him  that  if  he  did  so  I  would 
send  him  to  prison  for  life.  He  remained  about  the  farm 
for  some  months,  but  got  exceedingly  thin,  and  complained 
that  he  could  not  rest  or  eat,  that  his  wife's  spirit  was 
haunting  him,  because  he  had  not  taken  a  life  for  hers.  I 
was  inexorable,  and  assured  him  that  nothing  should  save 
him  if  he  did."  Nevertheless  the  man  disappeared  for 
more  than  a  year,  and  then  returned  in  high  condition  ; 
and  his  other  wife  told  Dr.  Landor  that  her  husband  had 
taken  the  life  of  a  woman  belonging  to  a  distant  tribe;  but 
it  was  impossible  to  obtain  legal  evidence  of  the  act.  The 
breach  of  a  rule  held  sacred  by  the  tribe  will  thus,  as  it 
seems,  give  rise  to  the  deepest  feelings — and  this  quite 
apart  from  the  social  instincts,  excepting  in  so  far  as  the 
rule  is  grounded  on  the  judgment  of  the  community. 
How  so  many  strange  superstitions  have  arisen  throughout 
the  world  we  know  not;  nor  can  we  tell  how  some  real  and 
great  crimes,  such  as  incest,  have  come  to  be  held  in  an 
abhorrence  (which  is  not  however  quite  universal)  by  the 
lowest  savages.  It  is  even  doubtful  whether  in  some  tribes 
incest  would  be  looked  on  with  greater  horror  than  would 
the  marriage  of  a  man  with  a  woman  bearing  the  same 
name,  though  not  a  relation.  *^'^  To  violate  this  law  is  a 
crime  which  the  Australians  hold  in  the  greatest  abhor- 
rence, ill  this  agreeing  exactly  with  certain  tribes  of  North 
America.  When  the  question  is  put  in  either  district,  is 
it  woi'se  to  kill  a  girl  of  a  foreign  tribe,  or  to  marry  a  girl 
of  one's  own,  an  answer  just  opposite  to  ours  would  be  given 
without  hesitation."!  ^^  J^^J?  therefore,  reject  the 
belief,  lately  insisted  on  by  some   writers,  that  the  abhor- 

*  "  Insanity  in  Relation  to    Law,"  Ontario,   United  States,    1871, 
pi. 
f  E.  B.  Tylor    in  "Contemporary  Review,"  April,  1873,  p. 707. 


MORAL  SENSE.  131 

rence  of  incest  is  due  to  our  possessing  a  special  God- 
implanted  conscience.  On  the  whole  it  is  intelligible,  that 
a  man  urged  by  so  powerful  a  sentiment  as  remorse  though 
arising  as  above  explained,  should  beledtoactin  a  manner, 
which  he  has  been  taught  to  believe  serves  as  an  expiation, 
such  as  delivering  himself  up  to  justice. 

Man  prompted  by  his  conscience,  will  through  long  habit 
acquire  such  perfect  self-command,  that  his  desires  and 
passions  will  at  last  yield  instantly  and  without  a  struggle 
to  his  social  sympathies  and  instincts,  including  his  feeling 
for  the  judgment  of  his  fellows.  The  still  hungry,  or  the 
still  revengeful,  man  will  not  think  of  stealing  food,  or  of 
wreaking  his  vengeance.  It  is  possible,  or  as  we  shall  here- 
after see,  even  probable,  that  the  habit  of  self-command 
may,  like  other  habits,  be  inherited.  Thus  at  last  man 
comes  to  feel,  through  acquired  and  perhaps  inherited 
habit,  tliat  it  is  best  for  him  to  obey  his  more  persistent 
impulses.  The  imperious  word  ought  seems  merely  to^ 
imply  the  consciousness  of  the  existence  of  a  rule  of  con- 
duct, however  it  may  have  originated.  Formerly  it  must 
have  been  often  vehemently  urged  that  an  insulted 
gentleman  ought  to  fight  a  duel.  We  even  say  that  a 
pointer  ought  to  point,  and  a  retriever  to  retrieve  game. 
If  they  fail  to  do  so,  they  fail  in  their  duty  and  act 
wrongly. 

If  any  desire  or  instinct  leading  to  an  action  opposed  t( 
the  good  of  others  still  appears,  when  recalled  to  mind, 
strong  as,  or  stronger  than,  the  social  instinct,  a  man  will 
feel  no  keen  regret  at  having  followed  it;  but  he  will  b( 
conscious  that  if  his  conduct  were  known  to  his  fellows,  it) 
would  meet  with  their  disapprobation;  and  few  are  so  desti- 
tute of  sympathy  as  not  to  feel  discomfort  when  this  is 
realized.  If  he  has  no  such  sympathy,  and  if  his  desires 
leading  to  bad  actions  are  at  the  time  strong,  and  when 
recalled  are  not  overmastered  by  the  persistent  social 
instincts,  and  the  judgment  of  others,  then  he  is  essen- 
tially a  bad  man;  *  and  the  sole  restraining  motive  left 
is  the  fear  of  punishment,  and  the  conviction  that  in  the 
long  run  it  would  be  best  for  his  own  selfish  interests  to 
regard  the  good  of  others  rather  than  his  own. 

*Dr.  Prosper  Despine  in  his  "  Psychologic  Naturelle,"  1868  (torn, 
i,  p.  243;  torn,  ii,  p.  169),  gives  many  curious  cases  of  the  worst 
criminals,  who  apparently  have  beec  entirely  destitute  of  conscience. 


132  THE  DESCENT  OF  MAN. 

It  is  obvious  that  every  one  may  with  an  easy  conscience 
gratify  his  own  desires,  if  they  do  not  interfere  with  his 
social  instincts,  that  is  with  the  <yood  of  others:  but  in 
order  to  l)e*quite  free  from  self-reproacli,  or  at  least  of 
anxiety,  it  is  almost  necessary  for  him  to  avoid  the  disap- 
probation, whether  reasonable  or  not,  of  his  fellow-men. 
Nor  must  he  break  through  the  fixed  habits  of  his  life, 
especially  if  these  are  supported  by  reason;  for  if  he  does, 
he  will  assuredly  feel  dissatisfaction.  He  must  likewise 
avoid  the  reprobation  of  the  one  God  or  gods  in  whom, 
according  to  his  knowledge  or  superstition,  he  may  believe; 
but  in  this  case  the  additional  fear  of  divine  punishment 
often  supervenes. 

The  Strictly  Social  Virtues  at  First  Alone  Regarded. — 
The  above  view  of  the  origin  and  nature  of  the  moral  sense, 
which  tells  us  what  we  ought  to  do,  and  of  the  conscience 
which  reproves  us  if  we  disobey  it,  accords  well  with  what 
we  see  of  the  early  and  undeveloped  condition  of  this  faculty 
in  mankind.  The  virtues  which  must  be  practiced,  at  least 
generally,  by  rude  men,  so  that  they  may  associate  in  a  body, 
are  those  which  aie  still  recognized  as  the  most  important. 
But  they  are  practiced  almost  exclusively  in  relation  to  the 
men  of  the  same  tribe;  and  their  opposites  are  not  regarded 
as  crimes  in  relation  to  the  men  of  other  tribes.  No  tribe 
could  hold  together  if  murder,  robbery,  treachery,  etc., 
were  common,  consequently  such  crimes  within  the  limits 
of  the  same  tribe  *^  are  branded  with  everlasting  infamy;''* 
but  excite  no  such  sentiment  beyond  these  limits.  A  North 
American  Indian  is  well  pleased  with  himself,  and  is  hon- 
ored by  others,  when  he  scalps  a  man  of  another  tribe;  and 
a  Dyak  cuts  oif  the  head  of  an  unoffending  person,  and 
dries  it  as  a  trophy.  The  murder  of  infants  has  prevailed 
on  the  largest  scale  throughout  the  world,!  and  has  met 
with  no  reproach;  but  infanticide,  especially  of  females, 
has  been  thought  to  be"  good  for  Ihe  tribe,  or  at  least  not 
injurious.     Suicide  during  former  times  was  not  generally 

*See  an  able  article  in  the  "  Nortli  British  Review,"  1867,  p.  395. 
See  also  Mr.  W.  Bagehot's  articles  on  the  "  Importance  of  Obedience" 
and  "  Coherence  to  Primitive  Man,"  in  the  "  Fortnightly  Review," 
1867,  p.  529,  and  1868,  p.  457,  etc. 

f  The  fullest  account  which  I  have  met  with  is  by  Dr.  Gerland,  in 
his  "  Ueber  dan  Aussterben  der  Naturvolker,"  1868;  but  I  shall  have 
to  recur  to  the  subject  of  infanticide  in  a  future  chapter. 


MORAL  SENSE.  133 

considered  as  a  crime,*  but  rather,  from  the  courage  dis- 
played, as  an  honorable  act;  and  it  is  still  practiced  by  some 
semi-civilized  and  savage  nations  without  reproach,  for  it 
does  not  obviously  concern  others  of  the  tribe.  It  has 
been  recorded  that  an  Indian  Thug  conscientiously  regret- 
ted that  he  had  not  robbed  and  strangled  as  many  trav- 
elers as  did  his  father  before  him.  In  a  rude  state  of 
civilization  the  robbery  of  strangers  is,  indeed,  generally 
considered  as  honorable. 

Slavery,  although  in  some  ways  beneficial  during  ancient 
times, t  is  a  great  crime;  yet  it  was  not  so  regarded  until 
quite  recently,  even  by  the  most  civilized  nations.  And 
this  was  especially  the  case,  because  the  slaves  belonged  in 
general  to  a  race  different  from  that  of  their  masters.  As 
barbarians  do  not  regard  the  opinions  of  their  women, 
wives  are  commonly  treated  like  slaves.  Most  savages  are 
utterly  indifferent  to  the  sufferings  of  strangers,  or  even 
delight  in  witnessing  them.  It  well  known  that  the  women 
and  children  of  the  Xorth  American  Indians  aided  in  tor- 
turing their  enemies.  Some  savages  take  a  horrid  pleas- 
ure in  cruelty  to  animals,  J  and  humanity  is  an  unknown 
virtue.  Nevertheless,  besides  the  family  affections,  kind- 
ness is  common,  especially  during  sickness,  between  the 
members  of  the  same  tribe,  and  is  sometimes  extended 
beyond  these  limits.  Mungo  Park's  touching  account  of 
the  kindness  of  the  negro  women  of  the  interior  to  him 
is  well  known.  Many  instances  could  be  given  of  the  noble 
fidelily  of  savages  toward  each  other,  but  not  to  strangers; 
common  experience  justifies  the  maxim  of  the  Spainard. 
"Never,  never  trust  an  Indian.''  There  cannot  be  fidelity 
without  truth  ;  and  this  fundamental  virtue  is  not  rare 
between  the  members  of  the  same  tribe;  thus  Mungo  Park 

*See  the  very  interesting  discussion  on  Suicide  in  Lecky's  "Hist- 
ory of  European  Morals,"  vol.  i,  1869,  p.  223.  With  respect  to  sav- 
ages, Mr.  Winwood  Reade  informs  me  that  the  negroes  of  West 
Africa  often  commit  suicide.  It  is  well  known  how  common  it  was 
among  the  miserable  Aborigines  of  South  America  after  the  Spanish 
conquest.  For  New  Zealand,  see  the  voyage  of  the  "Novara,"  and 
for  the  Aleutian  Islands,  Miiller,  as  quoted  by  Houzeau,  "  Les 
Facultes  Mentales,"  etc.,  tom.  ii,  p.  136. 

t  See  Mr.  Bagehot,  "Physics  and  Politics,"  1872,  p.  72. 

if  See,  for  instance,  Mr.  Hamilton's  account  of  the  Kaffirs,  "An- 
thropological Review,"  1870,  p.  15. 


134  THE  DESCENT  OF  MAN. 

heard  the  negro  women  teaching  their  young  children  to 
love  the  truth.  This,  again,  is  one  of  the  virtues  which 
becomes  so  deeply  rooted  in  the  mind  that  it  is  sometimes 
practiced  by  savages,  even  at  a  high  cost,  toward  strangers; 
but  to  lie  to  your  enemy  has  rarely  been  thought  a  sin,  as 
the  history  of  modern  diplomacy  too  plainly  shows.  As 
soon  as  a  tribe  has  a  recognized  leader  disobedience  becomes 
a  crime,  and  even  abject  submission  is  looked  at  as  a  sacred 
virtue. 

As  during  rude  times  no  man  can  be  useful  or  faithful  to 
his  tribe  without  courage,  tliis  quality  has  universally  been 
placed  in  the  highest  rank;  and  although  in  civilized  coun- 
tries a  good  yet  timid  man  may  be  far  more  useful  to  the 
community  than  a  brave  one,  we  cannot  help  instinctively 
honoring  the  latter  above  a  coward,  however  benevolent. 
Prudence,  on  the  other  hand,  which  does  not  concern  the 
welfare  of  others,  though  a  very  useful  virtue,  has  never 
been  highly  esteemed.  As  no  man  can  practice  the  virtues 
necessary  for  the  welfare  of  his  tribe  without  self-sacrifice, 
self-command,  and  the  power  of  endurance,  these  qualities 
have  been  at  all  times  highly  and  most  justly  valued.  The 
American  savage  voluntarily  submits  to  the  most  horrid 
tortures  without  a  groan,  to  prove  and  strengthen  his  forti- 
tude and  courage;  and  we  cannot  help  admiring  him,  or 
even  an  Indian  Fakir,  who,  from  a  foolish  religious  motive, 
swings  suspended  by  a  hook  buried  in  his  flesh. 

The  other  so-called  self-regarding  virtues,  which  do  not 
obviously,  though  they  may  really,  affect  the  welfare  of  the 
tribe,  have  never  been  esteemed  by  savages,  though  now 
highly  appreciated  by  civilized  nations.  The  greatest 
intemperance  is  no  reproach  with  savages.  Utter  licen- 
tiousness and  unnatural  crimes  prevail  to  an  astounding 
extent.*  As  soon,  however,  as  marriage,  whether  polyga- 
mous or  monogamous,  becomes  common,  jealousy  will  lead 
to  the  inculcation  of  female  virtue;  and  this  being  honored, 
will  tend  to  spread  to  the  unmarried  females.  How  slowly 
it  spreads  to  the  male  sex,  we  see  at  the  present  day. 
Chastity  eminently  requires  self-command;  therefore  it  has 
been  honored  from  a  very  early  period  in  the  moral  history 
of  civilized  man.  As  a  consequence  of  this,  the  senseless 
practice  of  celibacy  has  been  ranked  from  a  remote  period 

*Mr.  MLennan  lias  ofiven  ("  Primitive  Marriage,"  1865,  p.  176)  a 
good  collection  of  facts  on  tliis  bead. 


MOkAL  SENSE.  135 

as  a  virtue.  *  The  hatred  of  indecency,  which  appears  to 
lis  so  natural  as  to  be  thought  innate,  and  which  is  so  val- 
uable an  aid  to  chastity,  is  a  modern  virtue,  appertaining 
exclusively,  as  Sir  G.  Staunton  remarks,  f  to  civilized  life. 
This  is  shown  by  the  ancient  religious  rites  of  various 
nations,  by  the  drawings  on  the  walls  of  Pompeii,  and  by 
the  practices  of  many  savages. 

We  have  now  seen  that  actions  are  regarded  by  savagesj^ 
and  were  probably  so  regarded  by  primeval  man,  as  good  or 
bad,  solelv  as  thev  obviously  affect  the  welfare  of  the  tribe 
— not  that  of  the  species,  nor  that  of  an  individual  membej 
of  the  tribe.  This  conclusion  agrees  well  with  the  belie] 
that  the  so-called  moral  sense  is  aboriginally  derived  froi 
the  social  instincts,  for  both  relate  at  first  exclusively  t( 
the  community. 

The  chief  causes  of  the  low  morality  of  savages,  as 
judged  by  our  standard,  are,  firstly,  the  confinement  of 
sympathy  to  the  same  tribe.  Secondly,  powers  of  reason- 
ing insufficient  to  recognize  the  bearing  of  many  virtues, 
especially  of  the  self-regarding  virtues,  on  the  general  wel- 
fare of  the  tribe.  Savages,  for  instance,  fail  to  trace  the 
multiplied  evils  consequent  on  a  Avant  of  temperance, 
chastity,  etc.  And,  thirdly,  weak  power  of  self-command; 
for  this  power  has  not  been  strengthened  through  long-con- 
tinued, perhaps  inherited,  habit,  instruction  and  religion. 

I  have  entered  into  the  above  details  on  the  immorality 
of  savages,  J  because  some  authors  have  recently  taken  a 
high  view  of  their  moi-al  nature,  or  have  attributed  most  of 
their  crimes  to  mistaken  benevolence.  §  These  authors 
appear  to  rest  their  conclusion  on  savages  possessing  those 
virtues  which  are  serviceable,  or  even  necessary,  for  the 
existence  of  tlie  family  and  of  the  tribe — qualities  which 
they  undoubtedly  do  possess,  and  often  in  a  high  degree. 

Concluding  Remarks, — It  was  assumed  formerly  by  phi- 
losophers  of  the   derivative  ||    school  of  morals  that  the 

*  Lecky,  "  History  of  European  Morals,"  vol.  i,  1869,  p.  109. 

f  "  Embassy  to  China,"  vol.  ii,  p.  348. 

X  See  on  this  subject  copious  evidence  in  chap,  vii,  of  Sir  J.  Lub- 
bock, "Origin  of  Civilization,"  1870. 

§For  instance,  I-.ecky  "  Hist.  European  Morals,"  vol.  i,  p.  124. 

I  This  temi  is  used  in  an  able  article  in  the  "  Westminster  Re- 
view," Oct.,  1869,  p.  498.  For  the  "greatest  happiness  principle," 
see  J.  S.  Mill,  "  tJtilitarianism,"  p.  17. 


136  THE  DESCENT  OF  MAN, 

foundation  of  morality  lay  in  a  form  of  Selfishness;  but 
more  recently  the  ^'greatest  happiness  principle'^  has  been 
brought  prominently  forward.  It  is,  however,  more  cor- 
rect to  speak  of  the  latter  principle  as  the  standard,  and 
not  as  the  motive  of  conduct.  Nevertheless,  all  the  authors 
whose  works  I  have  consulted,  with  a  few  exceptions,* 
write  as  if  there  must  be  a  distinct  motive  for  every  action, 
and  that  this  must  be  associated  with  some  pleasure  or  dis- 
2)leasure.  But  man  seems  often  to  act  impulsively,  that  is 
from  instinct  or  long  habit,  without  any  consciousness  of 
pleasure,  in  the  same  manner  as  does  probably  a  bee  or  ant, 
when  it  blindly  follows  its  instincts.  Under  circumstances 
of  extreme  peril,  as  during  a  fire,  when  a  man  endeavors  to 
save  a  fellow-creature  without  a  moment's  hesitation,  he 
can  hardly  feel  pleasure;  and  still  less  has  he  time  to  reflect 
on  the  dissatisfaction  which  he  might  subsequently  experi- 
ence if  he  did  not  make  the  attempt.  Should  he  afterward 
reflect  over  his  own  conduct,  he  would  feel  that  there  lies 
within  him  an  impulsive  power  widely  different  from  a 
search  after  pleasure  or  happiness;  and  this  seems  to  be  the 
deeply  planted  social  instinct. 

In  the  case  of  the  lower  animals  it  seems  much  more 
appropriate  to  speak  of  their  social  instincts,  as  having 
been  developed  for  the  general  good  rather  than  for  the 
general  happiness  of  the  species.  The  term,  geT;ieral  good, 
may  be  defined  as  the  rearing  of  th^  grpatf^st  rmmhor  of 
indivirlnnis  i|^  fii11  vijyor  and  health,  with  all  their  facuTRes 
perfect,  under  the  conditions  to  which  they  are  subjected. 

*Mill  recognizes  ("  System  of  Logic,"  vol.  ii,  p.  422)  in  the  clear- 
est manner,  tliat  actions  may  be  performed  through  habit  without 
the  anticipation  of  pleasure.  Mr.  H.  Sidgwick  also,  in  his  essay  on 
Pleasure  and  Desire  ("  The  Contemporary  Review,"  April  1872,  p. 
671),  remarks:  "To  sum  up,  in  contravention  of  the  doctrine  that 
our  conscious  active  impulses  are  always  directed  toward  the  pro- 
duction of  agreeable  sensations  in  ourselves,  I  would  maintain  that 
we  find  everywhere  in  consciousness  extra-regarding  impulse,  di- 
rected toward  something  that  is  not  pleasure;  that  in  many  cases  the 
impulse  is  so  far  incompatible  with  the  self-regarding  that  the  two 
do  not  easily  co-exist  in  the  same  moment  of  consciousness."  A  dim 
feeling  that  our  impulses  do  not  by  any  means  always  arise  from  any 
contemporaneous  or  anticipated  pleasure,  has,  I  cannot  but  think, 
been  one  chief  cause  of  the  acceptance  of  the  intuitive  theory  of 
morality,  and  of  the  rejection  of  the  utilitarian  or  "greatest  happi- 
ness "  theory  With  respect  to  the  latter  theory  the  standard  and 
tl\e  motive  nf  conduct  have  no  doubt  often  been  confused,  but  they 
are  really  in  some  degree  blended. 


MORAL  SENSE.  137 

As  the  social  instincts  both  of  man  and  the  lower  animals 
have  no  doubt  been  developed  by  nearly  the  same  steps,  it 
would  be  advisable,  if  found  practicable,  to  use  the  same 
definition  in  both  cases,  and  to  take  as  the  standard  of 
moralitv  the  g^pn^rnl  p^nod.or  welfare  of  thecommunitv, 
rather  than  the  general  happiness ;  but  this  detiniiion 
would  perhaps  require  some  limitation  on  account  of 
political  ethics.  ^ 

When  a  man  risks  his  life  to  save  that  of  a  f ellow-creal 
ure  it  seems  also  more  correct  to  say  that  he  acts  for  tl 
general  good  rather  than  for  the  general  happiness  of  maj 
kind.  No  doubt  the  welfare  and  the  happiness  of  tl 
individual  usually  coincide;  and  a  contented,  happy  tripe 
will  flourish  better  than  one  that  is  discontented  and 
unhappy.  We  have  seen  that  even  at  an  early  period  i| 
the  history  of  man  the  expressed  wishes  of  the  communii 
will  have  naturally  influenced  to  a  large  extent  the  conduc 
of  each  member;  and  as  all  wish  for  happiness,  the  "  great 
est  happiness  principle  "  will  have  become  a  most  impoi 
tant  secondary  guide  and  object;  the  social  instinct,  hoi 
ever,  together  with  sympathy  (which  leads  to  our  regardini^ 
the  approbation  and  disapprobation  of  others),  having 
served  as  the  primary  impulse  and  guide.  Thus  the  re- 
proach is  removed  of  laying  the  foundation  of  the  noblesi 
part  of  our  nature  in  the  base  principle  of  selfishness  J 
unless,  indeed,  the  satisfaction  which  every  animal  feels,! 
when  it  follows  its  proper  instincts,  and  the  dissatisfaction' 
felt  when  prevented  be  called  selfish. 

The  wishes  and  opinions  of  the  members  of  the  same 
community,  expressed  at  first  orally  but  later  by  writing 
also,  either  form  the  sole  guides  of  our  conduct  or  greatly 
re-enforce  the  social  instincts;  such  opinions,  however,  have 
sometimes  a  tendency  directly  opposed  to  these  instincts^ 
This  latter  fact  is  well  exemplified  by  the  Lmoof  Hpnor\ 
that  is,  the  law  of  the  opinion  of  our  equals'aTnTnot  of  alll 
our  countrymen.     The  brea<3h  of  this  law,  even  when  thei 
breach  is  known  to  be  strictly  accordant  with  true  moral- 
ity, has  caused  many  a  man  more  agony  than  a  real  crime. 
AVe  recognize  the  same  influence  in  the  burning  sense  ot 
shame  which  most  of  us  have  felt,  even  after  the  intersal 
of  years,  wlien  calling  to  mind  some  accidental  breach  of  a 
trifling,  tliough  fixed  rule  of  etiquette.     The  judgment  of  j 
the  community   will   generally  be   guided   by  some  rude  i 


138  THE  DESCENT  OF  MAN. 

experience  of  what  is  best  in  the  long  run  for  all  the  mem- 
bers; but  this  judgment  will  not  rarely  err  from  ignorance 
and  weak  powers  of  reasoning.  Hence  the  strangest  cus- 
toms and  superstitions,  in  complete  opposition  to  tne  true 
welfare  and  happiness  of  mankind,  have  become  all-power- 
ful throughout  the  world.  We  see  this  in  the  horror  felt 
by  a  Hindoo  who  breaks  his  caste,  and  in  many  O'^her  such 
cases.  It  would  be  difficult  to  distinguish  between  the 
remorse  felt  by  a  Hindoo  who  has  yielded  to  the  tempta- 
tion of  eating  unclean  food  from  that  felt  after  committing 
a  theft;  but  the  former  would  probably  be  the  more  severe. 

How  so  many  absurd  rules  of  conduct,  as  well  as  so 
many  absurd  religious  beliefs,  have  originated,  we  do  not 
know;  nor  how  it  is  that  they  have  become,  in  all  quarters 
of  the  world,  so  deeply  impressed  on  the  minds  of  men; 
but  it  is  worthy  of  remark  that  a  belief  constantly  incul- 
cated during  the  early  years  of  life,  while  the  brain  is  im^ 
pressible,  appears  to  acquire  almost  the  nature  of  an 
instinct;  and  the  very  essence  of  an  instinct  is  that  it  is 
followed  independently  of  reason.  Neither  can  we  say  wny 
certain  admirable  virtues,  such  as  the  love  of  truth,  art 
much  more  highly  appreciated  by  some  savage  tribes  than 
by  others;*  nor,  again,  why  similar  differences  prevail  even 
among  highly  civilized  nations.  Knowing  how  firmly 
fixed  many  strange  customs  and  superstitions  have  become, 
we  need  feel  no  surprise  that  the  self-regarding  virtues, 
supported  as  they  are  by  reason,  should  now  appear  to  us 
so  natural  as  to  be  thought  innate,  although  they  were  not 
valued  by  man  in  his  early  condition. 

Notwithstanding  many  sources  of  doubt,  man  can  gener- 
ally and  readily  distinguish  between  the  higher  and  lower 
moral  rules.  The  higher  are  founded  on  the  social 
instincts,  and  relate  to  the  welfare  of  others.  They  are 
supported  by  the  approbation  of  our  fellow-men  and  by 
reason.  The  lower  rules,  though  some  of  them  when  im- 
plying self-sacrifice  hardly  deserve  to  be  called  lower,  relate 
chiefly  to  self,  and  arise  from  public  opinion,  matured  by 
[experience  and  cultivation;  for  they  are  not  practiced  by 
jrude  tribes. 

As   man  advances  in  civilization,  and  small  tribes  are 

*Good  instances  are  given  by  Mr,  Wallace  in  "  Scientific  Opinion," 
Sept.  15,  1869;  and  more  fully  in  his  "Contributions  to  the  Theory 
of  Natural  Selection,"  1870,  p.  353. 


MORAL  SENSE.  *  139 

united  into  larger  communities,  the  simplest  reason  would  * 
tell  each  individual  that  he  ought  to  extend  his  social  / 
instincts  and  sympathies  to  all  the  members  of  the  same/ 
nation,  though  personally  unknown  to  him.  This  pointJ 
being  once  reached,  there  is  only  an  artificial  barrier  to  preJ 
yent  his  sympathies  extending  to  the  men  of  all  nations 
and  races.  If,  indeed,  such  men  are  separated  from  him 
by  great  differences  in  appearance  or  habits,  experience 
unfortunately  shows  us  how  long  it  is,  before  we  look  at 
them  as  our  fellow-creatures.  Sympathy  beyond  the  con- 
fines of  man,  that  is,  humanity  to  the  lower  animals,  seems 
to  be  one  of  the  latest  moral  acquisitions.  It  is  apparently 
unfelt  by  savages,  except  toward  their  pets.  How  little 
the  old  Romans  knew  of  it  is  showTi  by  their  abhorrent 
gladiatorial  exhibitions.  The  very  idea  of  humanity,  as 
far  as  I  could  observe,  was  new  to  most  of  the  Gauchos  of 
the  Pampas.  This  virtue,  one  of  the  noblest  with  which 
man  is  endowed,  seems  to  arise  incidentally  from  our  sym- 
pathies becoming  more  tender  and  more  widely  diffused, 
until  they  are  extended  to  all  sentient  beings.  As  soon  ap 
this  virtue  is  honored  and  practiced  by  some  few  men,  i ; 
spreads  through  instruction  and  example  to  the  young,  an(  [ 
eventually  becomes  incorporated  in  public  opinion.  • 

The  highest  possible  stage  in  moral  culture  is  when  we 
recognize  that  we  ought  to  control  our  thoughts,  and 
''  not  even  in  inmost  thought  to  think  again  the  sins  that 
made  the  past  so  pleasant  to  us. ""*  Whatever  makes  any 
bad  action  familiar  to  the  mind  renders  its  performance 
by  so  much  the  easier.  As  Marcus  Aurelius  long  ago  said: 
''  Such  as  are  thy  habitual  thoughts,  such  also  will  be  the 
character  of  thy  mind ;  for  the  soul  is  dved  bv  the 
thoughts."! 

Our  great  philosopher,  Herbert  Spencer,  has  recently 
explained  his  views  on  the  moral  sense.  He  says: J  '^I 
believe  that  the  experiences  of  utility  organized  and  con- 
solidated through  all  past  generations  of  the  human  race, 
have  been  producing  corresponding  modifications,  which, 

*  Tennyson's  "  Idylls  of  the  King,"  p.  244. 

f  "The  Thoughts  of  the  Emperor  M.  Aurelius  Antoninus,"  Eng. 
translat.,  2d  edit.,  1869,  p.  112.  Marcus  Aurelius  was  born  a.  d. 
121. 

^ Letter  to  Mr,  Mill  in  Bains  "Mental  and  Moral  Science,"  1868, 
p.  722. 


140  •   THE  DESCENT  OF  MAN. 

by  continued  transmission  and  accumulation,  have  become 
in  us  certain  faculties  of  moral  intuition — certain  emotions 
responding  to  right  and  wrong  conduct,  which  have  no 
apparent  basis  in  the  individual  experiences  of  utility/'' 
There  is  not  the  least  inherent  improbability,  as  it  seems  to 
me,  in  virtuous  tendencies  being  more  or  less  strongly 
inherited;  for.  not  to  mention  the  various  dispositions  and 
habits  transmitted  by  many  of  our  domestic  animals  to 
their  offspring,  I  have  heard  of  authentic  cases  in  which  a 
desire  to  steal  and  a  tendency  to  lie  appeared  to  run  in 
families  of  the  upper  ranks;  and  as  stealing  is  a  rare  crime 
in  the  wealthy  classes^  we  can  hardly  account  by  accidental 
coincidence  for  the  tendency  of  occurring  in  two  or  three 
members  of  the  same  family.  If  bad  tendencies  are  trans- 
mitted, it  is  probable  that  good  ones  are  likewise  trans- 
mitted. That  the  state  of  the  body  by  affecting  the  brain 
has  great  influence  on  the  moral  tendencies  is  known 
to  most  of  those  who  have  suffered  from  chronic  derange- 
ments of  the  digestion  or  liver.  The  same  fact  is  likewise 
shown  by  the  *^  perversion  or  destruction  of  the  moral 
sense  being  often  one  of  the  earliest  symptoms  of  mental 
derangement;^^  *  and  insanity  is  notoriously  often  inherited. 
Except  through  the  principle  of  the  transmission  of  moral 
tendencies,  we  cannot  understand  the  differences  believed 
to  exist  in  this  respect  between  the  various  races  of 
mankind. 

Even  the  partial  transmission  of  virtuous  tendencies 
would  be  an  immense  assistance  to  the  primary  impulse 
derived  directly  and  indirectly  from  the  social  instincts. 
Admitting  for  a  moment  that  virtuous  tendencies  are 
inherited,  it  appears  probable,  at  least  in  such  cases  as 
chastity,  temperance,  humanity  to  animals,  etc.,  that  they 
become  first  impressed  on  the  mental  organization  through 
habit,  instruction  and  example,  continued  during  several 
generations  in  the  same  family,  and  in  a  quite  subordinate 
degree,  or  not  at  all,  by  the  individuals  possessing  such 
virtues  having  succeeded  best  in  the  struggle  for  life.  My 
chief  source  of  doubt  with  respect  to  any  such  inheritance, 
is  that  senseless  customs,  superstitions  and  tastes,  such  as 
the  horror  of  a  Hindoo  for  unclean  food,  ought  on  the  same 
principle   to  be  transmitted.     I  have  not  met  with  any 

*Maudsley,  "Body  and  Mind,"  1870,  p.  60. 


MORAL  SENSE,  141 

evidence  in  support  of  the  transmission  of  superstitious 
customs  or  senseless  habits,  although  in  itself  it  is  per- 
haps not  less  probable  than  that  animals  should  acquire 
inherited  tastes  for  certain  kinds  of  food  or  fear  of  certain 
foes. 

Finally  the  social  instincts,  which  no  doubt  were  acquired 
by  man  as  by  the  lower  animals  for  the  good  of  the  com- 
munity, will  from  the  first  have  given  to  him  some  wish  to 
aid  his  fellows,  some  feeling  of  sympathy,  and  have  com- 
pelled, him  to  regard  their  approbation  and  disapprobation. 
Such  impulses  will  have  served  him  at  a  very  early  period 
as  a  rude  rule  of  right  and  wrong.  But  as  man  gradually 
advanced  in  intellectual  power  and  was  enabled  to  trace  the 
more  remote  consequences  of  his  actions;  as  he  acquired 
sufficient  knowledge  to  reject  baneful  customs  and  super- 
stitions; as  he  regarded  more  and  more  not  only  the  wel- 
fare, but  the  happiness  of  his  fellow-men;  as  from  habit, 
following  on  beneficial  experience,  instruction  and  example, 
his  sympathies  became  more  tender  and  widely  diifused, 
extending  to  men  of  all  races,  to  the  imbecile,  maimed,  and 
other  useless  members  of  society,  and  finally  to  the  lower 
animals — so  would  the  standard  of  his  morality  rise  higher 
and  higher.  And  it  is  admitted  by  moralists  of  the  deriva- 
tive school  and  by  some  intuitionists,  that  the  standard  of 
morality  has  risen  since  an  early  period  in  the  history  of 
man.  * 

As  a  struggle  may  sometimes  be  seen  going  on  between  j 
the  various  instincts  of  the  lower  animals,  it  is  not  surpris-  I 
ing  that  there  should  be  a  struggle  in  man  between  his  I 
social  instincts,  with  their  derived  virtues,  and  his  lower,  I 
though  momentarily  stronger  impulses  or  desires.     This,  as  \ 
Mr.  Graltonf  has  remarked,  is  all  the  less  surprising,  as  man 
has  emerged  from  a  state  of  barbarism  within  a  compara- 
tively recent  period.     After  having  yielded  to  some  temp- 
tation we  feel  a  sense  of  dissatisfaction,  shame,  repentance, 

*  A  writer  in  the  "  North  British  Review  "  (July  1869,  p.  531), 
well  capable  of  forming  a  sound  judgment,  expresses  himself  strongly 
in  favor  of  this  conclusion.  Mr.  Lecky  (•'  Hist,  of  Morals,"  vol.  i,  p. 
143)  seems  to  a  certain  extent  to  coincide  therein. 

f  See  his  remarkable  work  on  "Hereditary  Genius,"  1869,  p.  349. 
The  Duke  of  Argyll  ("  Primeval  Man,"  1869,  p.  188)  has  some  good 
remarks  on  the  contest  in  nan's  nature  between  right  and  wrong. 


142  THK  DESCENT  OF  MAN. 

or  remorse,  analogous  to  the  feelings  caused  by  other  power- 
ful instincts  or  desires,  when  left  nnsatisfied  or  balked. 
We  compare  the  weakened  imjiression  of  a  past  temptation 
with  the  ever  present  social  instincts,  or  with  habits,  gained 
in  early  youth  and  strengthened  during  our  whole  lives 
until  they  have  become  almost  as  strong  as  instincts.  If 
with  the  temptation  still  before  us  we  do  not  yield,  it  is 
because  either  the  social  instinct  or  some  custom  is  at  the 
moment  predominant,  or  because  we  have  learned  that  it 
will  appear  to  us  hereafter  the  stronger,  when  compared 
with  the  weakened  impression  of  the  temptation,  and  we 
realize  that  its'  violation  would  cause  us  suffering.  Looking 
to  future  generations,  there  is  no  cause  to  fear  that  the 
social  instincts  will  grow  weaker,  and  we  may  expect  that! 
virtuous  habits  will  grow  stronger,  becoming  perhaps  fixed 
by  inheritance.  In  this  case  the  struggle  between  our| 
higher  and  lower  impulses  will  be  less  severe,  and  virtue 
will  be  triumphant. 

Summary  of  the  Last  Tiop  Chapters. — There  can  be  no 
doubt  that  the  difference  between  the  mind  of  the  lowest 
man  and  that  of  the  highest  animal  is  immense.  An 
anthropomorphous  ape,  if  he  could  take  a  dispassionate  view 
of  his  own  case,  would  admit  that  though  he  could  form 
an  artful  plan  to  plunder  a  garden — though  he  could  use 
stones  for  fighting  or  for  breaking  open  nuts,  yet  that  the 
thought  of  fashioning  a  stone  into  a  tool  was  quite  beyond 
his  scope.  Still  less,  as  he  would  admit,  could  he  follow 
out  a  train  of  metaphysical  reasoning,  or  solve  a  mathemat- 
ical problem,  or  reflect  on  God,  or  admire  a  grand  natural 
scene.  Some  apes,  however,  would  probably  declare  that 
they  could  and  did  admire  the  beauty  of  the  colored  skin 
and  fur  of  their  partners  in  marriage.  They  would  admit, 
that  though  they  could  make  other  apes  understand  by 
cries  some  of  their  perceptions  and  similar  wants,  the  notion 
of  expressing  different  ideas  by  definite  sounds  had  never 
crossed  their  minds.  They  might  insist  that  they  were 
ready  to  aid  their  fellow-apes  of  the  same  troop  in  many 
ways,  to  risk  their  lives  for  them,  and  to  take  charge  of 
their  orphans;  but  they  would  be  forced  to  acknowledge 
that  disinterested  love  for  all  living  creatures,  the  most 
noble  attribute  of  man,  was  quite  beyond  their  compre- 
hension. 


SUMMARY.  143 

Nevertheless  the  difference  in  mind  between  man  and 
the  higher  animals,  great  as  it  is,  certainly  is  one  of  degree 
and  not  of  kind.  We  have  seen  that  the  senses  and  intui- 
tions, the  various  emotions  and  faculties,  such  as  love, 
memory,  attention,  curiosity,  imitation,  reason,  etc.,  of 
which  man  boasts,  may  be  found  in  an  incipient,  or  even 
sometimes  in  a  well-developed  condition,  in  the  lower 
animals.  They  are  also  capable  of  some  inherited  improve- 
ment, as  we  see  in  the  domestic  dog  compared  with  the 
wolf  or  jackal.  If  it  could  be  proved  that  certain  high 
mental  powers,  such  as  the  formation  of  general  con- 
cepts, self-consciousness,  etc.,  were  absolutely  peculiar  to 
man,  which  seems  extremely  doubtful,  it  is  not  improbable 
that  these  qualities  are  merely  the  incidental  results  of 
other  highly-advanced  intellectual  faculties ;  and  these 
again  mainly  the  result  of  the  continued  use  of  a  perfect 
language.  At  what  age  does  the  new-born  infant  possess 
the  power  of  abstraction,  or  become  self-conscious  and 
reflect  on  its  own  existence  ?  We  cannot  answer;  nor  can 
we  answer  in  regard  to  the  ascending  organic  scale.  The 
half-art,  haK-instinct  of  language  still  bears  the  stamp 
of  its  gradual  evolution.  The  ennobling  belief  in  God  is 
not  universal  with  man;  and  the  belief  in  spiritual  agencies 
naturally  follows  from  other  mental  powers.  The  moral 
sense  perhaps  affords  the  best  and  highest  distinction 
between  man  and  the  lower  animals;  but  I  need  not  say 
nothing  on  this  head,  as  I  have  so  lately  endeavored  to 
show  that  the  SQiiiaLiusticts — the  prime  prn^^^jplp  nf  Tpa.n'« 
moral  constitution* — with  the  aid  of  active  intellectual 
powers  and  the1)ffects  of  habit,  naturally  lead  to  the  golden 
rule,  ''  As  ye  wom]<^  ^^«a^.  rn^n  should  do  to  vou,  do  ve  to 
tjiem  likewise;^^  and  this  lies  at  the  foundation  of  morality. 

In  the  next  chapter  i  shall  make  some  few  remarks  on  tne 
probable  steps  and  means  by  which  the  several  mental 
and  moral  faculties  of  man  have  been  gradually  evolved. 
That  such  evolution  is  at  least  possible,  ought  not  to  be 
denied,  for  we  daily  see  these  faculties  developing  in  every 
infant;  and  we  may  trace  a  pefect  gradation  from  the  mind 
of  an  utter  idiot,  lower  than  that  of  an  animal  low  in  the 
scale,  to  the  mind  of  a  Newton. 

*"The  Thoughts  of  Marcus  Aurelius,"  etc.,  p.  139. 


144  THE  DESCENT  OF  MAN, 


CHAPTER  V. 

ON"     THE      DEVELOPMENT      OF     THE     INTELLECTUAL     AND 

MORAL   FACULTIES   DURING    PRIMEVAL  AND 

CIVILIZED     TIMES. 

Advancement  of  the  intellectual  powers  through  natural  selection — 
Importance  of  imitation  —  Social  and  moral  faculties  —  Their 
development  within  the  limits  of  the  same  tribe — Natural 
selection  as  affecting  civilized  nations — Evidence  that  civilized 
nations  were  once  bafbarous. 

The  subjects  to  be  discussed  in  this  chapter  are  of  the 
highest  interest,  but  are  treated  by  me  in  an  imperfect  and 
fragmentary  manner.  Mr.  Wallace,  in  an  admirable  paper 
before  referred  to,*  argues  that  man,  after  he  had  partially 
acquired  those  intellectual  and  moral  faculties  which  dis- 
tinguish him  from  the  lower  animals,  would  have  been  but 
little  liable  to  bodily  modifications  through  natural  selec- 
tion or  any  other  means.  For  man  is  enabled  through  his 
mental  faculties  ''  to  keep  with  an  unchanged  body  in  har- 
mony with  the  changing  universe."^  He  has  great  power 
of  adapting  his  habits  to  new  conditions  of  life.  He 
invents  weapons,  tools,  and  various  stratagems  to  procure 
food  and  to  defend  himself.  When  he  migrates  into  a 
colder  climate  he  uses  clothes,  builds  sheds,  and  makes 
fires;  and  by  the  aid  of  fire  cooks  food  otherwise  indigesti- 
ble. He  aids  his  fellow-men  in  many  ways,  and  anticipates 
future  events.  Even  at  a  remote  period  he  practiced  some 
division  of  labor. 

The  lower  animals,  on  the  other  hand,  must  have  their 
bodily  structure  modified  in  order  to  survive  under  greatly 
changed  conditions.  They  must  be  rendered  stronger,  or 
acquire  more  eifective  teeth  or  claws,  for  defense  against 
new  enemies;  or  they  must  be  reduced  in  size,  so  as  to 

*  "Anthropological  Review,"  May,  1864,  p.  158. 


INTELLECTUAL  FACULTIES.  145 

escape  detection  and  danger.  When  tliey  migrate  into  a 
colder  climate,  they  must  become  clothed  with  thicker  fur, 
or  have  their  constitutions  altered.  If  they  fail  to  be  thus 
modified,  they  will  cease  to  exist. 

The  case,  however,  is  widely  different,  as  Mr.  Wallace 
has  with  justice  insisted,  in  relation  to  the  intellectual  and 
moral  faculties  of  man.  These  faculties  are  variable;  and 
we  have  every  reason  to  believe  that  the  variations  tend  to 
be  inherited.  Therefore,  if  they  were  formerly  of  high 
importance  to  primeval  man  and  to  his  ape-like  progenitors, 
they  would  have  been  perfected  or  advanced  through 
natural  selection.  Of  the  high  importance  of  the  intel- 
lectual faculties  there  can  be  no  doubt,  for  man  mainly 
owes  to  them  his  predominant  position  in  the  world.  AVe 
can  see,  that  in  the  rudest  state  of  society,  the  individuals 
who  were  the  most  sagacious,  who  invented  and  used  the 
best  weapons  or  traps,  and  who  were  best  able  to  defend 
themselves,  would  rear  the  greatest  number  of  offspring. 
The  tribes,  which  included  the  largest  number  of  men  thus 
endowed,  would  increase  in  number  and  supplant  other 
tribes.  Numbers  depend  primarily  on  the  means  of  sub- 
sistence, and  this  depends  partly  on  the  physical  nature  of 
the  country,  but  in  a  much  higher  degree  on  the  arts 
which  are  there  practiced.  As  a  tribe  increases  and  is  vic- 
torious, it  is  often  still  further  increased  by  the  absorption 
of  other  tribes.  *  The  stature  and  strength  of  the  men  of  a 
tribe  are  likewise  of  some  importance  for  its  success,  and 
these  depend  in  part  on  the  nature  and  amount  of  the 
food  which  can  be  obtained.  In  Europe  the  men  of  the 
Bronze  period  were  supplanted  by  a  race  more  powerful, 
■  and,  judging  from  their  sword-handles,  with  larger  hands;f 
but  their  success  was  probably  still  more  due  to  their 
•  superiority  in  the  arts. 

All  that  we  know  about  savages,  or  may  infer  from  their 
traditions  and  from  old  monuments,  the  history  of  which 
is  quite  forgotten  by  the  present  inhabitants,  show  that 
from  the  remotest  times  successful  tribes  have  supplanted 
other  tribes.  Relics  of  extinct  or  forgotten  tribes  have  been 
discovered  throughout  the  civilized  regions  of  the  earth,  on 

*  After  a  time  the  members  or  tribes  which  are  absorbed  into 
another  tribe  assume,  as  Sir  Henry  Maine  remarks  ("Ancient  Law," 
1861,  p.  131),  that  they  are  the  co-descendants  of  the  same  ancestors. 

tMorlot,  "Soc.  Vaud.  Sc.  Nat,"  1860,  p.  294. 


146  THE  DESCENT  OF  MAN, 

the  wild  plains  of  America,  and  on  the  isolated  islands  in 
the  PaciMc  Ocean.  At  the  present  day  civilized  nations 
are  everywhere  supplanting  barbarous  nations,  excepting 
where  the  climate  opposes  a  deadly  barrier;  and  they  suc- 
ceed mainly,  though  not  exclusively,  through  their  arts, 
which  are  the  products  of  the  intellect.  It  is,  therefore, 
highly  probable  that  with  mankind  the  intellectual  facul- 
ties have  been  mainly  and  gradually  perfected  through 
natural  selection;  and  this  conclusion  is  sufficient  for  our 
purpose.  Undoubtedly  it  would  be  interesting  to  trace  the 
development  of  each  separate  faculty  from  the  state  in 
which  it  exists  in  the  lower  animals  to  that  in  which  it 
exists  in  man;  but  neither  my  ability  nor  knowledge  per- 
mits the  attempt. 

It  deserves  notice  that  as  soon  as  the  progenitors  of  man 
became  social  (and  this  probably  occurred  at  a  very  early 
period),  the  principal  of  imitation  and  reason  and  experi- 
ence would  have  increased  and  much  modified  the  intel- 
lectual powers  in  a  way,  of  which  we  see  only  traces  in  the 
lower  animals.  Apes  are  much  given  to  imitation,  as  are 
the  lowest  savages;  and  the  simple  fact  previously  referred 
to,  that  after  a  time  no  animal  can  be  caught  in  the  same 
place  by  the  same  sort  of  trap,  shows  that  animals  learn  by 
experience  and  imitate  the  caution  of  others.  Now,  if  some 
one  man  in  a  tribe,  more  sagacious  than  the  others,  invented 
a  new  snare  or  weapon,  or  other  means  of  attack  or  defense, 
the  plainest  self-interest,  without  the  assistance  of  much 
reasoning  power,  would  prompt  the  other  members  to  imi- 
tate him;  and  all  would  thus  profit.  The  habitual  practice 
of  each  new  art  must  likewise  in  some  slight  degree 
strengthen  the  intellect.  If  the  new  invention  were  an 
important  one,  the  tribe  would  increase  in  number,  spread, 
and  supplant  other  tribes.  In  a  tribe  thus  rendered  more 
numerous  there  would  always  be  a  rather  greater  chance  of 
the  birth  of  other  superior  and  inventive  members.  If 
such  men  left  children  to  inherit  their  mental  superiority, 
the  chance  of  the  birth  of  still  ntore  ingenious  members 
would  be  somewhat  better,  and  in  a  very  small  tribe  decid- 
edly better.  Even  if  they  left  no  children,  the  tribe  would 
still  include  their  blood-relations;  and  it  has  been  ascer- 
tained by  agriculturists*  that  by  preserving  and  breeding 

*  I  have  given  instances  in  my  "  Variation  of  Animals  under  Dq- 
Wjestication,"  vol.  ii,  p.  196. 


MORAL  FACULTIES,  147 

from  the  family  of  an  animal  which  when  slaughtered  was 
found  to  be  valuable,  the  desired  character  has  been 
obtained. 

Turning  now  to  the  social  and  moral  faculties.  In  order 
that  primeval  men,  or  the  ape-like  progenitors  of  man, 
should  become  social,  they  must  have  acquired  the  same 
instinctive  feelings,  which  impel  other  animals  to  live  in  a 
body;  and  they  no  doubt  exhibited  the  same  general  dispo- 
sition. They  would  have  felt  uneasy  when  separated  from 
their  comrades,  for  whom  they  would  have  felt  some  degree 
of  love;  they  would  have  warned  each  other  of  danger,  and 
have  given  mutual  aid  in  attack  or  defense.  All  this  im- 
plies some  degree  of  sympathy,  fidelity  and  courage.  Such 
social  qualities,  the  paramount  importance  of  which  to  the 
lower  animals  is  disputed  by  no  one,  were  no  doubt  acquired 
by  the  progenitors  of  man  in  a  similar  manner,  namely, 
through  nfli-i]p^]  splppfimi.  aided  bv  inhpTitpH  ha  hit.    When 

"  two  trlDes  of  primeval  man,  living  in  the  same  country, 
came  into  competition^  if  (other  circumstances  being  equal) 
the  one  tribe  included  a  great  number  of  courageous,  sym- 
pathetic and  faithful  members,  who  were  always  ready  to 
warn  each  other  of  danger,  to  aid  and  defend  each  other, 
this  tribe  would  succeed  better  and  conquer  the  other.    Let 
it  be  borne  in  mind  how  all-important  in  the  never-ceasing 
wars  of  savages,  fidelity  and  courage  must  be.    The  advan- 
tage  which   disciplined   soldiers  have   over  undisciplined 
hordes  follows  chiefly  from  the  confidence  which  each  man 
feels  in  his  comrades.     Ohedipnce,  ^r  ^fr.  Bnjorphot  haswell|| 
shown.*  is  of  the  hi,<^hest  vate^fpr  ^^'Y  f^^^  ^f  grnvpTTlpipptl 
"i8"^tter  than  none.     Selfish  and  contentious  people  willl 
not  cohere,  and  without  coherence  nothing  can  be  effected.  \ 

*  A  tribe  rich  in  the  above  qualities  would  spread  and  be 
victorious  over  other  tribes;  but  in  the  course  of  time  it 
would,  judging  from  all  past  history,  be  in  its  turn  over- 
come by  some  other  tribe  still  more  highly  endowed.  Thus 
the  social  and  moral  qualities  would  tend  slowly  to  advance 
and  be  diffused  throughout  the  world. 

But  it  may  be  asked,  how  within  the  limits  of  the  same 
tribe  did  a  large  number  of  members  first  become  endowed 

*See  a  remarkable  series  of  articles  on  "  Phvsics  and  Politics,"  in 
the  "  Fortnightly  Review,"  Nov.,  1867;  April*  1,  1868;  July  1, 
since  separately  published. 


148  THE  DESCENT  OF  MAN. 

with  these  social  and  moral  qualities,  and  how  was  the 
standard  of  excellence  raised?  It  is  extremely  doubtful 
whether  the  offspring  of  the  more  sympathetic  and  benevo- 
lent parents,  or  of  those  who  were  the  most  faithful  to 
their  comrades,  would  be  reared  in  greater  numbers  than 
the  children  of  selfish  and  treacherous  parents  belonging  to 
the  same  tribe.  He  who  was  ready  to  sacrifice  his  life,  as 
many  a  savage  has  been,  rather  than  betray  his  comrades, 
would  often  leave  no  offspring  to  inherit  his  noble  nature. 
The  bravest  men,  who  were  always  willing  to  come  to  the 
front  in  war,  and  who  freely  risked  their  lives  for  others, 
would  on  an  average  perish  in  larger  numbers  than  other 
men.  Therefore  it  hardly  seems  probable,  that  the  number 
of  men  gifted  with  such  virtues,  or  that  the  standard  of 
their  excellence  could  be  increased  through  natural  selec- 
tion, that  is,  by  the  survival  of  the  fittest ;  for  we  are  not 
here  speaking  of  one  tribe  being  victorious  over  another. 

Although  the  circumstances,  leading  to  an  increase  in 
the  number  of  those  thus  endowed  within  the  same  tribe 
are  too  complex  to  be  clearly  followed  out  we  can  trace 
some  of  the  probable  steps.  Jn^ilie  first  place,  as  the  rea- 
soning powers  and  foresight  of  the  members  became  im- 
proved, each  man  would  soon  learn  that  if  he  aided  hi^ 
fellow-men  he  would  commonly  receive  aid  in  return. 
I  From  this  Ioav  motive  he  might  acquire  the  habit  of  aiding 
I  his  fellows;  and  the  habit  of  performing  benevolent  actions 
certainly  strengthens  the  feeling  of  sympathy  which  gives 
the  first  impulse  to  benevolent  actions.  Habits,  more- 
over, followed  during  many  generations  probably  tend  to 
be  inherited. 

But  another  and  much  more  powerful  stimulus  to  the 
development  of  the  social  virtues  is  afforded  by  the  praise 
and  the  blame  of  our  fellow-men.  To  the  instinct  of 
sympathy,  as  we  have  already  seen,  it  is  primarily  due  that 
we  habitually  bestow  both  praise  and  blame  on  others, 
while  we  love  the  former  and  dread  the  latter  when  applied 
to  ourselves;  and  this  instinct  no  doubt  was  originally 
acquired,  like  all  the  other  social  instincts,  through  nat- 
ural selection.  At  how  early  a  period  the  progenitors  of 
man  in  the  course  of  their  development  became  capable  of 
feeling  and  being  impelled  by  the  praise  or  blame  of  their 
fellow-creatures  we  cannot  of  course  say.  But  it  appears 
that  even    dogs    appreciate  encouragement,   praise,   and 


MonAL  FACXTLT1E8.  149 

blame.  The  rudest  savages  feel  the  sentiment  of  glory,  as 
they  clearly  show  by  preserving  the  trophies  of  their 
prowess,  by  their  habit  of  excessive  boasting,  and  even  by 
the  extreme  care  which  they  take  of  their  personal  appear- 
ance and  decorations;  for  unless  they  regarded  the  opinion 
of  their  comrades  such  habits  would  be  senseless. 

They  certainly  feel  shame  at  the  breach  of  some  of  their 
lesser  rules,  and  apparently  remorse,  as  shown  by  the  case 
of  the  Australian  who  grew  thin  and  could  not  rest  from 
having  delayed  to  murder  some  other  woman  so  as  to  pro- 
pitiate his  dea<i  wife's  spirit.  Though  I  have  not  met  with 
any  other  recorded  case,  it  is  scarcely  credible  that  a  savage 
who  will  sacrifice  his  life  rather  than  betray  his  tribe,  or  one 
who  will  deliver  himself  up  as  a  prisoner  rather  than  break 
his  parole,*  would  not  feel  remorse  in  his  inmost  sole  if  he 
had  failed  in  a  duty  which  he  held  sacred. 

AVe  may  therefore  conclude  that  prim  ft  val  m^tn,  at  a  ^^'y* 
remote  pe^i^fl,  ^^-g  iTiflnpnpprI    hy  \\\e.   praiso  and  blame  of  .' 
biR  fftllows._  It  is  obvious  that  the  members  of  the  same , 
tribe  would  approve  of  condnrt  whiph  apppared  to  them,  to  j 
be  for  the  g^eneral  good,  aiidwould  reprobate  that  which  \ 
agpeai'ed  eviL    To  do  good  unto  others — to  do  unto  others  as  I 
yft  wm^TfTTHfty  should  do  unto  you — is  the  foundation  stone 
oT  morality.     It  is,  therefore,  hardly 'possible  to  exaggerate 
the  importance  during  rude  times  of  the  love  of  praise  and 
the  dzead  of  blame.     A  man  who  was  nof  impelled  %  any 
deep,  instinctive  feeling,  to  sacrifice  his  life  for  the  good 
of  others,  yet   was  roused  to  such  actions  by  a  sense  of 
glory,  would  by  his  example  excite  the  same  wish  for  glory 
in  other  men,  and  would  strengthen  by  exercise  the  noble 
feeling  of  admiration.     He  might  thus  do  far  more  good  to 
his  tribe  than  hy  begetting  offspring  with  a  tendency  to 
inherit  his  own  high  character. 

With  increased  experience  and  reason,  man  perceives  the 
more  remote  consequences  of  his  actions,  and  the  self -regard- 
ing virtues,  such  as  temperance,  chastity,  etc.,  which  during 
early  times  are,  as  we  have  before  seen,  utterly  disregarded, 
come  to  be  highly  esteemed  or  even  held  sacred.  I  need 
not,  however,  repeat  what  I  have  said  on  this  head  in  the  ti 
fourth  chapter.  Ultimately  our  moral  sense  or  conscience  If 
becomes  a  highly  complex  sentiment — originating  in  theW 

*  Mr.  Wallace  gives  cases  in  bis  "Contributions  to  tbe  Tbeory  of 
Natural  Selection,"  1870,  p.  354. 


150  ^SE  MSGENf  OF  MAN. 

social  instincts,  largely  guided  by  the  approbation  of  ouf 
fellow-men,  ruled  by  reason,  self-interest,  and  in  later 
times  by  deep  religious  feelings,  and  confirmed  by  instruc- 
tion and  habit. 

It  must  not  be  forgotten  that  although  a  high  standard 
of  morality  gives  but  a  slight  or  no  advantage  to  each 
individual  man  and  his  children  over  the  other  men  of  the 
same  tribe,  yet  that  an  increase  in  the  number  of  well- 
endowed  men  and  an  advancement  in  the  standard  of 
morality  will  certainly  give  an  immense  advantage  to  one 
tribe  over  another.  A  tribe  including  many  members  who, 
from  possessing  in  a  high  degree  the  spirit  of  patriotism,  fidel- 
ity, obedience,  courage  and  sympathy,  were  always  ready  to 
aid  one  another,  and  to  sacrifice  themselves  for  the  common 
good,  would  be  victorious  over  most  other  tribes;  and  this 
would  be  natural  selection.  At  all  times  throughout  the 
world  tribes  have  supplanted  other  tribes;  and  as  morality 
is  one  important  element  in  their  success,  the  standard  of 
morality  and  the  number  of  well-endowed  men  will  thus 
everywhere  tend  to  rise  and  increase. 

It  is,  however,  very  difficult  to  form  any  judgment  why 
one  particular  tribe  and  not  another  has  been  successful 
and  has  risen  in  the  scale  of  civilization.  Many  savages 
are  in  the  same  condition  as  when  first  discovered  several 
centuries  ago.  As  Mr.  Bagehot  has  remarked,  we  are  apt 
toJ^)ak-gt#-^i;:agress  a,s  normal  in  human  sodjatv;  but  "History 
rftfntfts  f.his.  Tte  ancients  did  not  even  entertanTthelSea, 
nor  do  the  Oriental  nations  at  the  present  day.  According 
to  another  high  authority.  Sir  Henry  Maine,*  '^^  the  greatest 
part  of  mankind  has  never  shown  a  particle  of  desire  that  its 
civil  institutions  should  be  improved."  ,,Erogress  seems  to 
depend  on  many  concurrent  favorable  conditions,  far  too 
complex  to  be  followed  out.  But  it  has  often  been  remarked, 
that  a  cool  climate,  from  leading  to  industry  and  to  the 
various  arts,  has  been  highly  favorable  thereto.  The  Esqui- 
maux, pressed  by  hard  necessity,  have  succeeded  in  many 
ingenious  inventions,  but  their  climate  has  been  too  severe 
for  continued  progress.  Nomadic  habits,  whether  over  wide 
plains,  or  through  the  dense  forests  of  the  tropics,  or  along 
the  shores  of  the  sea,  have  in  every  case  been  highly  detri- 
mental.     While   observing   the   barbarous  inhabitants   of 

* "  Ancient  Law,"  1861,  p.  22.  For  Mr.  Bagehot's  remarks, 
"  Fortnightly  Review,"  April  1,  1868,  p.  452. 


CIVILIZED  NATtOirS.  151 

Terra  del  Fuego,  it  struck  me  that  the  possession  of  some 
property,  a  fixed  abode,  and  the  union  of  many  families  under 
a  chief,  were  the  indispensable  requisites  for  civilization. 
Such  habits  almost  necessitate  the  cultivation  of  the  ground; 
and  the  first  steps  in  cultivation  would  probably  result,  as 
I  have  elsewhere  shown,*  from  some  such  accident  as  the 
seeds  of  a  fruit-tree  falling  on  a  heap  of  refuse,  and  pro- 
ducing an  unusually  fine  variety.  The  problem,  however, 
of  the  first  advance  of  savages  toward  civilization  is  at  pres- 
ent much  too  difficult  to  be  solved. 

Natural  Selection  as  Affecting  Civilized  Nations. — I  have 
hitherto  only  considered  the  advancement  of  man  from  a 
semi-human  condition  to  that  of  the  modern  savage.  But 
some  remarks  on  the  action  of  natural  selection  on  cjyjlized 
I  nations  may  be  worth  aaamg^  This  subject  has  been  ably 
*  discussed  by  Mr.  W.  K.  Greg,  \  and  previously  by  Mr.  WaU 
lace  and  Mr.  Gal  ton.  |  Most  of  my  remarks  are  taken  from\ 
these  three  authors.  With  savages,  the  weak  in  body  or' 
mind  are  soon  eliminated;  and  those  that  survive  commonly 
exhibit  a  vigorous  state  of  health.  We  civilized  men,  on 
the  other  hand,  do  our  utmost  to  check  the  process  of  elim- 
ination; we  build  asylums  for  the  imbecile,  the  maimed, 
and  the  sick;  we  institute  poor-laws;  and  our  medical  men 
exert  their  utmost  skill  to  save  the  life  of  every  one  to  the 
last  moment.  There  is  reason  to  believe  that  vaccination 
has  preserved  thousands,  who  from  a  weak  constitution 
would  formerly  have  succumbed  to  small-pox.  Thus  the 
we^k  members  of  civilized  societies  propng^ff^  JJ2fvr_kjr^fl- 
iXo  one  who  has  attended  to  the  breeding  of  domestic  ani- 

*"The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  i,  p.  309. 

f  "Eraser's  Magazine,"  Sept.,  1868,  p.  353.  This  article  seems  to 
have  struck  many  persons,  and  has  given  rise  to  two  remarkable 
essays  and  a  rejoinder  in  the  "Spectator,"  Oct.  3  and  17,  1868.  It 
has  also  been  discussed  in  the  "  Q.  Journal  of  Science,"  1869,  p.  152, 
and  by  Mr.  Lawson  Tait  in  the  "Dublin  Q.  Journal  of  Medical 
Science,"  Feb.,  1869,  and  by  Mr.  E.  Ray  Lankestester  in  his  "Com- 
parative Longevity,"  1870,  p.  128.  Similar  views  appeared  pre- 
viously in  the  "  Australasian,"  July  13, 1867.  I  have  borrowed  idea.s 
from  several  of  these  writers. 

:|:ForMr.  Wallace,  see  "  Anthropolog.  Review,"  as  before  cited. 
Mr.  Oalton  in  "  Macmillan's  Magazine,"  Aug.,  1865,  p.  318;  also  his 
great  work,  "Hereditary  Genius,"  1870. 


r 


152  THE  DESCENT  OF  MAN. 

inals  will  doubt  that  this  must  be  highly  injurious  to  the 
irace  of  man.  It  is  surprising  how  soon  a  want  of  care,  or 
/care  wrongly  directed,  leads  to  the  degeneration  of  a  domes- 
tic race;  but  excepting  in  the  case  of  man  himself,  hardly 
any  one  is  so  ignorant  as  to  allow  his  worst  animals  to 
breed. 

The  aid  which  we  feel  impelled  to  give  to  the  helpless  is 
mainly  an  incidental  result  of  th^instinct  of  sympathy, 
which  was  originally  acquired  as  partS'  the  social  instincts, 
but  subsequently  rendered,  in  the  manner  previously  indi- 
cated,  more  tender  and  more  widely  diffused.  Nor  could 
we  che^k  ^"^'  "yrnpjltbY  even  at  the  urging  of  hamreason, 
t  ^f^tfrinn^ti^n  in  th^  noblest  part  of  our  nature, 
'The  surgeon  may  Uaraen  liimseli  while  periorming  an  oper- 
ation,  for  he  knows  that  he  is  acting  for  the  good  of  his 
patient;  but  if  we  were  intentionally  to  neglect  the  weak 
and  helpless,  it  could  only  be  for  a  contingent  benefit,  with 
an  overwhelming  present  evil,  ^f  We  must  therefore  bear  the 
undoubtedly  bad  effects  of  the  weak  surviving  and  propa- 
gating their  kind;  but  there  appears  to  be  at  least  one  check 
in  steady  action,  namely,  that  the  weaker  and  inferior 
members  of  society  do  not  marry  so  freely  as  the  sound;  and 
this  check  might  be  indefinitely  increased  by  the  weak  in 
body  or  mind  refraining  from  marriage,  though  this  is  more 
to  be  hoped  for  than  expected. 

In  every  country  in  which  a  large  standing  army  is  kept 
up,  the  finest  young  men  are  taken  by  the  conscription  or 
are  enlisted.  They  are  thus  exposed  to  early  death  during 
war,  are  often  tempted  into  vice,  and  are  prevented  from 
marrying  during  the  prime  of  life.  On  the  other  hand,  the 
shorter  and  feebler  men,  with  poor  constitutions,  are  left  at 
home,  and  consequently  have  a  much  better  chance  of 
marrying  and  propagating  their  kind.* 

Man  accumulates  property  and  bequeaths  it  to  his  chil- 
dren, so  that  the  children  of  the  rich  have  an  advantage 
over  the  poor  in  the  race  for  success,  independently  of 
bodily  or  mental  superiority.  On  the  other  hand,  the 
children  of  parents  who  are  short-lived,  and  are  therefore 
on  an  average  deficient  in  health  and  vigor,  come  into  their 
property  sooner  than   other  children,   and   will  be  likely 

*Prof.  H.  Fick  ("  Einfluss  der  Naturwissenscliaft  aiif  das  Recht," 
Jane,  1872)  lias  some  good  remai'ks  on  this  head,  and  on  other  snch 
points. 


CIVILIZED  NATIONS,  153 

to  marry  earlier,  and  leave  a  larger  number  of  offspring  U 
inherit  their  inferior  constitutions.  But  the  inheritance  o ' 
proper t}"  by  itself  is  very  far  from  an  evil;  for  without  th(5 
accumulation  of  capital  the  arts  could  not  progress;  and  i ; 
is  chiefly  through  their  power  that  the  civilized  races  hav( 
extended,  and  are  now  everywhere  extending  their  range, 
so  as  to  take  the  place  of  the  lower  races.  Nor  does  th( 
moderate  accumulation  of  wealth  interfere  with  the  procee 
of  selection.  When  a  poor  man  becomes  moderately  rich, 
his  children  enter  trades  or  professions  in  which  there  is| 
struggle  enough,  so  that  the  able  in  body  and  mind  succeed 
best.  The  presence  of  a  boc^y  of  wfll-^^"^^^^^^^^^  ^^^j  who 
have  not  to  labor  for  their  daily  bread,  is  important  to  a 
degree  which  cannot  be  overestimated;  as  all  high  intel- 
lectual work  IS  carriect  on  hy  them,  and  on  such  worJF. 
"material  progress  of  all  kinds  mainly  depends^_not_tii- men- 
tion  other  and  hit^t'^l'  Hj'^a^^'^g^°  i\o  doubt  wealth  when 
very  great  tends  to  convert  men  into  useless  drones,  but 
their  number  is  never  large;  and  some  degree  of  elimina- 
tion here  occurs,  for  we  daily  see  rich  men,  who  happen  to 
be  fools  or  profligates,  squandering  away  their  wealth. 

Primogeniture  with  entailed  estates  is  a  more  direct  evil, 
though  it  may  formerly  have  been  a  great  advantage  by  the  /  -p 
creation  of  a  dominant  class,  and  any  government  is  better !  * 
than  none.  Most  eldest  sons,  though  they  mayHje  weak  ml 
body  or  mind,  marry,  while  the  younger  sons,  however 
superior  in  these  respects,  do  not  so  generally  marry.  Nor 
can  worthless  eldest  sons  with  entailed  estates  squander 
their  wealth.  But  here,  as  elsewhere,  the  relations  of 
civilized  life  are  so  complex  that  some  compensatory  checks 
intervene.  The  men  who  are  rich  through  primogeniture 
are  able  to  select  generation  after  generation  the  more 
beautiful  and  charming  women;  and  these  must  generally 
be  healthy  in  body  and  active  in  mind.  The  evil  conse- 
quences, such  as  they  may  be,  of  the  continued  preserva- 
tion of  the  same  line  of  descent,  without  any  selection,  are 
checked  by  men  of  rank  always  wishing  to  increase  their 
wealth  and  power ;  and  this  they  effect  by  marrying 
heiresses.  But  the  daughters  of  parents  who  have  produced 
single  children,  are  themselves,  as  Mr.  Galton  *  has  shown, 
apt  to  be  sterile;  and  thus  noble  families  are  continually 

*  ••  Hereditary  Genius,"  1870,  pp.  132-140. 


It 


154  THSi  DH8CBNT  OP'  MAN. 

cut  off  in  the  direct  line,  and  their  wealth  flows  Into  sOril^ 
side  channel ;  but  unfortunately  this  channel  is  not 
determined  by  superiority  of  any  kind. 
/  Although  civilization  thus  checks  in  many  ways  the  action 
I  of  natural  selection,  it  apparently  favors  the  better  develop- 
■,ment  of  the  body,  by  means  of  good  food  and  the  freedom 
from  occasional  hardships.  This  may  be  inferred  from 
civilized  men  having  been  found,  wherever  compared,  to  be 
physically  stronger  than  savages.*  They  appear  also  to  have 
equal  powers  of  endurance,  as  has  been  proved  in  many 
adventurous  expeditions.  Even  the  great  luxury  of  the 
rich  can  be  but  little  detrimental;  for  the  expectation  of 
life  of  our  aristocracy,  at  all  ages  and  of  both  sexes,  is  very 
little  inferior  to  that  of  healthy  English  lives  in  the  lower 
classes,  f 

We  will  now  look  to  the  intellectual  faculties.  If  in 
each  grade  of  society  the  members  were  divided  into  two 
equal  bodies,  the  one  including  the  intellectually  superior 
and  the  other  the  inferior,  there  can  be  little  doubt  that  the 
former  would  succeed  best  in  all  occupations,  and  rear  a 
greater  number  of  children.  Even  in  the  lowest  walks  of 
life,  skill  and  ability  must  be  of  some  advantage;  though 
in  many  occupations,  owing  to  the  great  division  of  labor, 
a  very  small  one.  Hence  in  civilized  nations  there  will  be 
some  tendency  to  an  increase  both  in  the  number  and  in 
the  standard  of  the  intellectually  able.  But  I  do  not  wish 
to  assert  that  this  tendency  may  not  be  more  than  counter- 
balanced in  other  ways,  as  by  the  multiplication  of  the  reck- 
less and  improvident;  but  even  to  such  as  these,  ability 
must  be  some  advantage. 

It  has  often  been  objected  to  views  like  the  foregoing, 
that  the  most  eminent  men  who  have  ever  lived  l[^ive  left 
no  offspring  to  inherit  their  great  intellect.  Mr.  Galton 
says: J  ^'  I  regret  I  am  unable  to  solve  the  simple  question 
whether,  and  how  far,  men  and  women  who  are  prodigies 
of  genius  are  infertile.  I  have,  however,  shown  that  men 
of  eminence  are  by  no  means  so."     Great  lawgivers,  the 

* Quatref ages,  "Revue  des  Cours  Scientifiques,"  1867-68,  p.  659. 

\  See  the  fifth  and  sixth  columns,  compiled  from  good  authorities, 
in  the  table  given  in  Mr.  E.  \i.  Lankester's  "  Comparative  Longev- 
it:."1870,  p.  115. 

f  Hereditary  Genius,"  1870,  p.  330. 


Ol  VILIZeD  NA  TlOlfS.  155 

founders  of  beneficent  religions,  great  philosophers  and  dis- 
coverers in  science,  aid  the  progress  of  mankind  in  a  far 
higher  degree  by  their  works  than  by  leaving  a  numerous 
progeny.  In  the  case  of  corporeal  structures,  it  is  the 
selection  of  the  slightly  better-endowed  and  the  elimination 
of  the  slightly  less  well-endowed  individuals,  and  not 
the  preservation  of  strongly-marked  and  rare  anomalies, 
that  leads  to  the  advancement  of  a  species.*  So  it  will  be 
with  the  intellectual  faculties,  since  the  somewhat  abler 
men  in  each  grade  of  society  succeed  rather  better  than  the 
less  able,  and  consequently  increase  in  number,  if  not  other-; 
wise  prevented.  When  in  any  nation  the  standard  of  intelf 
lect  and  the  number  of  intellectual  men  have  increased,  we 
may  expect  from  the  law  of  the  deviation  from  an  average , 
that  prodigies  of  genius  will,  as  shoTVTi  by  Mr.  Galton, 
appear  somewhat  more  frequently  than  before. 

In  regard  to  the  moral  qualities,  some  elimination  of  th  \ 
worst  dispositions  is  always  in  progress  even  in  the  most 
civilized  nations.  Malefactors  are  executed,  or  imprisoned 
for  long  periods,  so  that  they  cannot  freely  transmit  their 
bad  qualities.  Melancholic  and  insane  persons  are  confined 
or  commit  suicide.  Violent  and  quarrelsome  men  often 
come  to  a  bloody  end.  The  restless  who  will  not  follow 
any  steady  occupation — and  this  relic  of  barbarism  is  a 
great  check  to  civilization f — emigrate  to  newly-settled 
countries,  where  they  prove  useful  pioneers.  Intemperance 
is  so  highly  destructive  that  the  expectation  of  life  of  the 
intemperate  at  the  age  of  thirty  for  instance,  is  only  13.8 
years;  while  for  the  rural  laborers  of  England  at  the  same 
age  it  is  40.59  years.  |  Profligate  women  bear  few  children, 
and  profligate  men  rarely  marry;  both  suffer  from  disease. 
In  the  breeding  of  domestic  animals,  the  elimination  of 
those  individuals,  though  few  in  number,  which  are  in  any 
marked  manner  inferior,  is  by  no  means  an  unimportant 
element  toward  success.  This  especially  holds  good  with 
injurious  characters  which  tend  to  reappear  through  rever- 
sion, such  as  blackness  in  sheep;  and  with  mankind  some 

*  "  Origin  of  Species"  (fifth  edition,  1869),  p.  104. 

t  "  Hereditary  Genius,"  1870,  p.  347. 

JE.  Ray  Lankester,  "  Comparative  Longevity,"  1870,  p.  115.  The 
table  of  the  intemperate  is  from  Neison's  "  Vital  Statistics."  In 
regard  to  profligacy,  see  Dr.  Farr,  "  Influence  of  Marriage  on  Mor- 
tality," "Nat.  Assoc,  for  the  Promotion  of  Social  Science,"  1858. 


156  THE  DESCENT  OF  MAN. 

of  the  worst  dispositions,  which  occasionally  withont  any 
assignable  cause  make  their  appearance  in  families,  may 
perhaps  be  reversions  to  a  savage  state,  from  which  we  are 
liot  removed  by  very  many  generations.  This  view  seems 
indeed  recognized  in  the  common  expression  that  such  men 
ire  the  black  sheep  of  the  family. 

With  civilized  nations,  as  far  as  an  advanced  standard  of 
morality,  and  an  increased  number  of  fairly  good  men  are 
concerned,  natural  selection  apparently  effects  but  little; 
though  the  fundamental  social  instincts  were  originally 
thus  gained.  But  I  have  already  said  enough,  while  treat- 
ing of  the  lower  races,  on  the  causes  which  lead  to  the 
advance  of  morality,  namely,  the  approbation  of  our  fellow- 
men — the  strengthening  of  our  sympathies  by  habit — exam- 
ple and  imitation — reason — experience,  and  even  self-inter- 
est— instruction  during  youth,  and  religious  feelings. 

A  most  important  obstacle  in  civilized  countries  to  an 
'increase  in  the  number  of  men  of  a  superior  class  has  been 
strongly  insisted  on  by  Mr.  Greg  and  Mr.  Gal  ton,*  namely, 
the  fact  that  the  very  poor  and  reckless,  who  are  often 
degraded  by  vice,  almost  invariably  marry  early,  while  the 
careful  and  frugal,  who  are  generally  otherwise  virtuous, 
marry  late  in  life,  so  that  they  may  be  able  to  support 
themselves  and  their  children  in  comfort.  Those  who 
/  marry  early  produce  within  a  given  period  not  only  a 
greater  number  of  generations,  but,  as  shown  by  Dr.  Dun- 
can,! tl^^y  pi'oduce  many  more  children.  The  children, 
moreover,  that  are  born  by  mothers  during  the  prime  of 
life  are  heavier  and  larger,  and  therefore  probably  more 
vigorous,  than  those  born  at  other  periods.  Thus  the 
reckless,  degraded,  and  often  vicious  members  of  so- 
ciety, tend  to  increase  at  a  quicker  rate  than 
the  provident  and  generally  virtuous  members.  Or,  as  Mr. 
Greg  puts  the  case:  ^^  The  careless,  squalid,  unaspiring 
Irishman  multiplies  like   rabbits;  the   frugal,  foreseeing, 

*"  Eraser's  Magazine,"  Sept.,  1868,  p.  353.  "  Macmillan's  Maga- 
zine," Aug.,  1865,  p.  318.  The  Rev.  F.  W.  Farrar  ("  Eraser's  Mag.," 
Aug. ,  1870,  p.  264)  takes  a  different  view. 

f  "  On  the  Laws  of  the  Fertility  of  Women,"  in  "  Transact.  Royal 
Soc,"  Edinburgh,  vol.  xxiv.  p.  287;  now  published  separately  under 
the  title  of  "  Fecundity,  Fertility  and  Sterility,"  1871.  See,  also, 
Mr.  Qalton,  "  Plereditary  Genius,"  pp.  352-357,  for  observations  to 
the  above  effect. 


CIVILIZED  NATIONS.  157 

self-respecting,  ambitious  Scot,  stern  in  his  morality, 
spiritual  in  his  faith,  sagacious  and  disciplined  in  his  intel- 
ligence, passes  his  best  years  in  struggle  and  in  celibacy, 
marries  late,  and  leaves  few  behind  him.  Given  a  land 
originally  peopled  by  a  thousand  Saxons  and  a  thousand 
Celts — and  in  a  dozen  generations  five-sixths  of  the  popu- 
lation would  be  Celts,  but  five-sixths  of  the  property,  of 
the  power,  of  the  intellect,  would  belong  to  the  one-sixth 
of  Saxons  that  remained.  In  the  eternal  ^  struggle  for  e: 
istence '  it  would  be  the  inferior  and  less  favored  race  tha| 
had  prevailed — and  prevailed  by  virtue  not  of  its  gooc 
qualities  but  of  its  faults.  ^^ 

There  are,  however,  some  checks  to  this  downward  ten- 
dency. We  have  seen  that  the  intemperate  suffer  from  a 
high  rate  of  mortality,  and  the  extremely  profligate  leave 
few  offspring.  The  poorest  classes  crowd  into  towns,  and 
it  has  been  proved  by  Dr.  Stark  from  the  statistics  of  ten 
years  in  Scotland*  that  at  all  ages  the  death  rate  is  higher 
in  towns  than  in  rural  disticts,  ''  and  during  the  first  five 
years  of  life  the  town  death  rate  is  almost  exactly  double 
that  of  the  rural  districts."  As  these  returns  include  both 
the  rich  and  the  poor,  no  doubt  more  than  twice  the 
number  of  births  would  be  requisite  to  keep  up  the  number 
of  the  very  poor  inhabitants  in  the  towns  relatively  to  those 
in  the  country.  With  women,  marriage  at  too  early  an 
age  is  highly  injurious;  for  it  has  been  found  in  France 
that  ^^  twice  as  many  wives  under  twenty  die  in  the  year 
as  died  out  of  the  same  number  of  the  unmarried."  The 
mortality,  also,  of  husbands  under  twenty  is  "  excessively 
high,"t  but  what  the  cause  of  this  may  be  seems  doubtful. 
Lastly,  if  the  men  who  prudently  delay  marrying  until 
they  can  bring  up  their  families  in  comfort  were  to  select, 
as  they  often  do,  women  in  the  prime  of  life,  the  rate  of 
increase  in  the  better  class  would  be  only  slightly  lessened. 

It  was  established  from  an  enormous  body  of  statistics, 
taken  during  1853,  that  the  unmarried  men  throughout 
France,  between  the  ages  of  twenty  and  eighty,  die  in  a 

*  **  Tentli  Annual  Report  of  Births,  Deaths,"  etc.,  in  Scotland, 
1867,  p.  29. 

f  These  quotations  are  taken  from  our  highest  authority  on  such 
questions,  namely.  Dr.  Farr,  in  his  paper  "  On  the  Influence  of  Mar- 
riage on  the  Mortality  of  the  French  People,"  read  before  the  Nat. 
Assoc,  for  the  Promotion  of  Social  Science,  1858. 


158  THE  DESCENT  OF  MAN, 

much  larger  proportion  than  the  married;  for  instance,  out 
of  every  1,000  unmarried  men,  between  the  ages  of  twenty 
and  thirty,  11.3  annually  died,  while  of  the  married  only 
6.5  died.*  A  similar  law  was  proved  to  hold  good,  during 
the  years  1863  and  1864,  with  the  entire  population 
above  the  age  of  twenty  in  Scotland;  for  instance,  out 
of  every  1,000  unmarried  men  between  the  ages  of 
twenty  and  thirty,  14,97  annually  died,  while  of  the  mar- 
ried only  7.24  died,  that  is  less  than  half.f  Dr.  Stark 
remarks  on  this:  ^'  Bachelorhood  is  more  destructive 
to  life  than  the  most  unwholesome  trades,  or  than 
residence  in  an  unwholesome  house  or  district  where  there 
has  never  been  the  most  distant  attempt  at  sanitary  improve- 
ment." He  considers  that  the  lessened  mortality  is  the 
direct  result  of  '^marriage,  and  the  more  regular  domestic 
habits  which  attend  that  state."  He  admits,  however,  that 
the  intemperate,  profligate,  and  criminal  classes,  whose 
duration  of  life  is  low,  do  not  commonly  marry;  and  it 
must  likewise  be  admitted  that  men  with  a  weak  constitu- 
tion, ill-health,  or  any  great  infirmity  in  body  or  mind,  will 
often  not  wish  to  marry,  or  will  be  rejected.  Dr.  Stark 
seems  to  have  come  to  the  conclusion  that  marriage  in 
itself  is  a  main  cause  of  prolonged  life,  from  finding  that 
aged  married  men  still  have  a  considerable  advantage  in 
this  respect  over  the  unmarried  of  the  same  advanced  age; 
but  every  one  must  have  known  instances  of  men,  who  with 
weak  health  during  youth  did  not  marry,  and  yet  have  sur- 
vived to  old  age,  though  remaining  weak,  and  therefore 
always  with  a  lessened  chance  of  life  or  of  marrying.  There 
is  another  remarkable  circumstance  which  seems  to  sup- 
port Dr.  Stark^s  conclusion,  namely,  that  widows  and 
widowers  in  France  suflier  in  comparison  with  the  married 
a  very  heavy  rate  of  mortality;  but  Dr.  Farr  attributes  this 
to  the  poverty  and  evil  habits  consequent  on  the  disruption 
of  the  family  and  to  grief.  On  the  whole  we  may  conclude 
with  Dr.  Farr  that  the  lesser  mortality  of  married  than  of 

*  Dr.  Farr,  ibid.  The  quotations  given  below  are  extracted  from 
the  same  striking  paper. 

f  I  have  taken  the  mean  of  the  quinquennial  means,  given  in  "  The 
Tenth  Annual  Report  of  Births,  Deaths,  etc.,  in  Scotland,"  1867. 
The  quotation  from  Dr.  Stark  is  copied  from  an  article  in  the  "  Daily 
News,"  Oct.  17,  1868,  whicl;  Dr.  Farr  considers  very  carefully 
written. 


CIVILIZED  NATIONS.  159 

unmarried  men,  which  seems  to  be  a  general  law,  '^is 
mainly  due  to  the  constant  elimination  of  imperfect  types, 
and  to  the  skillful  selection  of  the  finest  individuals  out  of 
each  successive  generation;"  the  selection  relating  only  to 
the  marriage  state,  and  acting  on  all  corporeal,  intellectual, 
and  moral  qualities.*  We  may,  therefore,  infer  that  sound 
and  good  men  who  out  of  prudence  remain  for  a  time 
unmarried  do  not  suffer  a  high  rate  of  moi-tality. 

If  the  various  checks  specified  in  the  two  last  paragraphs,  I 
and  perhaps  others  as  yet  unknown,  do  not  prevent  the 
reckless,  the  vicious  and  otherwise  inferior  members  of 
society  from  increasing  at  a  quicker  rate  than  the  better 
class  of  men,  the  nation  will  retrograde,  as  has  too  often 
occurred  in  the  history  of  the  world.  We  must  remember 
that  progress  is  no  invariable  rule.  It  is  very  difficult  to 
say  why  one  civilized  nation  rises,  becomes  more  powerful, 
and  spreads  more  widely,  than  another;  or  why  the  same 
nation  progresses  more  quickly  at  one  time  than  at  another. 
j^We  can  only  say  that  it  depends  on  an  increase  in  the  actual 
number  of  the  population,  on  the  number  of  the  men 
endowed  with  high  intellectual  and  moral  faculties,  as  well 
as  on  their  standard  of  excellence.  Corporeal  structure 
appears  to  have  little  influence,  except  so  far  as  vigor  of 
body  leads  to  vigor  of  mind.  V 

It  has  been  urged  by  several  writers  that  as  high  intellec-  r 
tual  powers  are  advantageous  to  a  nation,  the  old  Greeks,  • 
who  stood  some  grades  higher  in  intellect  than  any  race  that 
has  ever  existed,!  ought,  if  the  power  of  natural  selection 
were  real,  to  have  risen  still  higher  in  the  scale,  increased 
in  number,  and  stocked  the  whole  of  Europe.  Here  we 
have  the  tacit  assumption,  so  often  made  with  respect  to 
corporeal  structures,  that  there  is  some  innate  tendency 
toward  continued  development  in  mind  and  body.  But 
development  of  all  kinds  depends  on  many  concun*ent 
favorable  circumstances.  Natural  selection  acts  only  tenta- 
tively. Individuals  and  races  may  have  acquired  certain 
indisputable  advantages,  and  yet  have  perished  from  failing 

*Dr.  Duncan  remarks  ("Fecundity,  Fertility,"  etc.,  1871,  p.  334) 
on  tliis  subject:  "  At  every  age  the  healthy  and  beautiful  go  over 
from  the  unmarried  side  to  the  married,  leaving  the  unmarried 
columns  crowded  with  the  sickly  and  unfortunate." 

f  See  the  ingenious  and  original  argument  on  this  subject  by  Mr. 
Gal  ton,  *'  Hereditary  Genius,"  pp.  340-342. 


160  THE  DESCENT  OF  MAN. 

in  other  characters.  The  Greeks  may  have  retrograded 
from  a  want  of  coherence  between  the  many  small  states, 
from  the  small  size  of  their  whole  country,  from  the 
practice  of  slavery,  or  from  extreme  sensuality;  for  they  did 
not  succumb  until  ''  they  were  enervated  and  corrupt  to 
the  very  core."*  The  western  nations  of  Europe,  who  now 
so  immeasurably  surpass  their  former  savage  progenitors 
and  stand  at  the  summit  of  civilization,  owe  little  or  none 
of  their  superiority  to  direct  inheritance  from  the  old 
Greeks,  though  they  owe  much  to  the  written  works  of  that 
wonderful  people. 

Who  can  positively  say  why  the  Spanish  nation,  so  domi- 
nant at  one  time,  has  been  distanced  in  the  race.  The 
awakening  of  the  nations  of  Europe  from  the  dark  ages  is 
a  still  more  perplexing  problem.  At  that  early  period,  as 
Mr.  Galton  has  remarked,  almost  all  the  men  of  a  gentle 
nature,  those  given  to  meditation  or  culture  of  the  mind, 
had  no  refuge  except  in  the  bosom  of  a  Church  which 
demanded  celibacy;  \  and  this  could  hardly  fail  to  have  had 
a  deteriorating  influence  on  each  successive  generation. 
During  this  same  period  the  Holy  Inquisition  selected  with 
extreme  care  the  freest  and  boldest  men  in  order  to  burn  or 
imprison  them.  In  Spain  alone  some  of  the  best  men — 
those  who  doubted  and  questioned,  and  without_doubtinff 
there  can  bp.  r^n  progress — were  eliminated  during"  three 
centuries  at  the  rate  of  a  thousand  a  year.  The  evil  which 
the  Catholic  Church  has  thus  effected  is  incalculable, 
though  no  doubt  counterbalanced  to  a  certain,  perhaps  to 
a  large,  extent  in  other  ways;  nevertheless,  Europe  has 
progresged-at  an  unparalleled  rate.  " 

^TTKeremarkable^'stn^cess'of  the  English  as  colonists,  com- 
pared to  other  European  nations,  has  been  ascribed  to 
their  ^'^  daring  and  persistent  energy;"  a  result  which  is 
well  illustrated  by  comparing  the  progress  of  the  Canadians 
of  English  and  French  extraction;  but  who  can  say  how 
the   English  gained   their  energy  ?     There   is   apparently 

*Mr.  Greg,  "Fraser's  Magazine,"  Sept.,  1868,  p.  357. 

f "  Hereditary  Genius,"  1870,  pp.  357-359.  The  Rev.  F.  W. 
Farrar  ("  Fraser's  Mag.,"  Aug.  1870,  p.  257)  advances  arguments  on 
the  other  side.  Sir  C.  Lyell  had  already  ("  Principles  of  Geology," 
vol.  ii,  1868,  p.  489)  in  a  striking  passage  called  attention  to  the  evil 
influence  of  the  Holy  Inquisition  in  having,  through  selection, 
lowered  the  general  standard  of  intelligence  in  Europe. 


CIVILIZED  NATIONS.  161 

much  truth  in  the  belief  that  the  wonderful  progress  \  /f 
of  the  United  States,  as  well  as  the  character  of  the 
people,  are  the  results  of  natural  selection;  for  the  more 
energetic,  restless,  and  courageous  men  from  all  parts  of 
Europe  have  emigrated  during  the  last  ten  or  twelve 
generations  to  that  great  country,  and  have  there  succeeded 
best.  *  Looking  to  the  distant  future,  I  do  not  think  that 
the  Rev.  Mr.  Zincke  takes  an  exaggerated  view  when  he 
says :  f  *'A11  other  series  of  events  —  as  that  which 
resulted  in  the  culture  of  mind  in  Greece,  and  that  which 
resulted  in  the  empire  of  Rome — only  appear  to  have  pur- 
pose and  value  when  viewed  in  connection  with,  or  rather 
as  subsidiary  to  .  ,  .  the  great  stream  of  Anglo-Saxon 
emigration  to  the  west."'  Obscure  as  is  the  problem  of  the\ 
advance  of  civilization,  we  can  at  least  see  that  a  nation  I 
which  produced  during  a  lengthened  period  the  greatest 
number  of  highly  intellectual,  energetic,  brave,  patriotic 
and  benevolent  men,  would  generally  prevail  over  less 
favored  nations. 

^N^atural  selection  follows  from  the  strn^jp^le  for  existence;  r^ 
ancTthis  from  a  rapid  rate  of  increase.  Itis impossible  not  p 
to  regret  bitterly,  but  whether  wisely  is  another  question,  \ 
the  rate  at  which  man  tends  to  increase;  for  this  leads  in  \  K 
barbarous  tribes  to  infanticide  and  many  other  evils,  and  in  \  -jjr* 
civilized  nations  to  abject  poverty,  celibacy,  and  to  the  late 
marriages  of  the  prudent.  But  as  man  suffers  from  the 
same  physical  evils  as  the  lower  animals,  he  has  no  right  to 

'  expect  an  immunity  from  the  evils  consequent  on  the  strug- 
gle for  existence.  Had  he  not  been  subjected  during 
primeval  times  to  natural  selection,  assuredly  he  would 
never  have  attained  to  his  present  rank.  Since  we  see  in 
many  parts  of  the  world  enormous  areas  of  the  most  fertile 
land  capable  of  supporting  numerous  happy  homes,  but 
peopled  only  by  a  few  wandering  savages,  it  might  be 
argued  that  the  struggle  for  existence  had  not  been  suf- 
ficiently severe  to  force  man  upAvard  to  his  highest  standard. 

,  Judging  from  all  that  we  know  of  man  and  the  lower  ani- 
mals, there  has  always  been  sufficient  variability  in  their 
intellectual    and    moral   faculties,   for    a  steady  advance 

*Mr.  Galton,  "  Macmillan's  Magazine,"  Aug.,  1865,  p.  325.  See 
also  "Nature,"  "On  Darwinism  and  National  Life,"  Dec,  1869,  p. 
184. 

f  "Last  Winter  in  the  United  States,"  1868,  p.  29. 


162  THE  DESCENT  OF  MAN. 

through  natural  selection.  No  doubt  such  advance 
demands  many  favorable  concurrent  circumstances;  but  it 
may  well  be  doubted  whether  the  most  favorable  would  have 
sufficed,  had  not  the  rate  of  increase  been  rapid,  and  the 
consequent  struggle  for  existence  extremely  severe.  It  even 
appears  from  what  we  see,  for  instance,  in  parts  of  South 
America,  that  a  people  which  may  be  called  civilized,  such 
as  the  Spanish  settlers,  is  liable  to  become  indolent  and  to 
retrograde,  when  the  conditions  of  life  are  very  easy.  .,\^th 
highly  civilized  nations  continued  progress  depends _m]j 
"subordinatedegree  on  natural  selection;  for  such  nations 
do  not  supplant  and  exterminate  one  another  as  do  savage 
tribes.  Nevertheless  the  more  intelligent  members  within 
the  same  community  will  succeed  better  in  the  long  run 
than  the  inferior,  and  leave  a  more  numerous  progeny,  an " 
this  is  a  form  of  natural  selection.  The  more  efficien 
causes  of  progress  seem  to  consist  of  a  p^ood  ^  e^ucatio 
during  youth  while  the  brain  is  impressible 
«tpndard  of  excellence,  inculcated  by^the  ablest  and 
mea^^^mbodied  m  the  laws,  customs  ahn  tracHtioiis  oFTh 
nation,  and  enrorcea  by  public  opinion!  It  should,  howeve: 
be  borne  in  mind  that  the  enforcement  of  public  opinion  d^ 
pends  on  our  appreciation  of  the  approbation  and  disapproba- 
tion of  others;  and  this  appreciation  is  founded  on  our  sympa- 
thy, which  it  can  hardly  be  doubted  was  originally  developed 
Uhrough  natural  selection  as  one  of  the  most  important 
jelements  of  the  social  instincts.* 

On  the  Evidence  That  All  Civilized  Natiojis  Were  Once 
Barbarous. — The  present  subject  has  been  treated  in  so  full 
and  admirable  a  manner  by  Sir  J.  Lubbock,  \  Mr.  Tylor, 
Mr.  McLennan  and  others,  that  I  need  here  give  only  the 
briefest  summary  of  their  results.  The  arguments  recently 
advanced  by  the  Duke  of  Argyll  |  and  formerly  by  Arch- 
bishop Whately,  in  favor  of  the  belief  that  man  came  into 
the  world  as  a  civilized  being,  and  that  all  savages  have 
since  undergone  degradation,  seem  to  me  weak  in  compari- 

^  I  am  much  indebted  to.  Mr.  John  Morley  for  some  good  criticisms 
on  this  subject:  see,  also,  Broca,  "Les  Selections,"  "Revue  d'An- 
tbropologie,"  1872. 

f "  On  tbe  Origin  of  Civilization,"  "  Proc.  Ethnological  Soc," 
Nov    26,  1867. 

t"  Primeval  Man,"  1869 


CIVILIZED  NATIONS.  163 

Bon  with  those  advanced  on  the  other  side.  Many  nations, 
no  douht,  have  fallen  away  in  civilization,  and  some  may 
have  lapsed  into  utter  barbarism,  though  on  this  latter  head 
I  have  met  with  no  evidence.  The  Fuegianswere  probably 
compelled  by  other  conquering  hordes  to  settle  in  their 
inhospitable  country,  and  they  may  have  become  in  conse- 
quence somewhat  more  degraded;  but  it  would  be  difficult 
to  prove  that  they  have  fallen  much  below  the  Botocudos, 
who  inhabit  the  finest  parts  of  Brazil. 

The  evidence  that  all  ci\ilized  nations  are  the  descend- 
ants of  barbarians,  consists,  on  the  one  side,  of  clear  traces 
of  their  former  low  condition  in  still-existing  customs, 
beliefs,  language,  etc.;  and  on  the  other  side,  of  proofs 
that  savages  are  independently  able  to  raise  themselves  a 
few  steps  in  the  scale  of  civilization,  and  have  actually  thus 
risen.  The  evidence  on  the  first  head  is  extremely  curious, 
but  cannot  be  here  given;  I  refer  to  such  cases  as  that  of 
the  art  of  enumeration,  which,  as  Mr.  Tylor  clearly  shows 
by  reference  to  the  words  still  used  in  some  places,  origi- 
nated in  counting  the  fingers,  first  of  one  hand  and  then  of 
the  other,  and  lastly  of  the  toes.  We  have  traces  of  this 
in  our  own  decimal  system,  and  in  the  Eoman  numerals, 
where,  after  the  V,  which  is  supposed  to  be  an  abbreviated 
picture  of  a  human  hand,  we  pass  on  to  YI,  etc.,  when 
the  other  hand  no  doubt  was  used.  So  again,  *^  when  we 
speak  of  three-score  and  ten,  we  are  counting  by  the  vigesi- 
mal system,  each  score  thus  ideally  made,  standing  for  20 — 
for  *one  manias  a  Mexican  or  Carib  would  put  it."* 
According  to  a  large  and  increasing  school  of  philologists, 
every  language  bears  the  marks  of  its  slow  and  gradual  evo- 
lution. So  it  is  with  the  art  of  writing,  for  letters  are 
rudiments  of  pictorial  representations.  It  is  hardly  possi- 
ble to  read  Mr.  M'Lennan's  work  f  and  not  admit  that 
almost  all  civilized  nations  still  retain  traces  of  such  rude 
habits  as   the  forcible   capture  of   wives.     What  ancient 

*"  Royal  Institution  of  Great  Britain,"  March  15,  1867.  Also 
"  Researches  Into  the  Early  History  of  Mankind,"  1865. 

f  "  Primitive  Marriage,"  1865.  See,  likewise,  an  excellent  article, 
evidently  by  the  same  author,  in  the  "  North  British  Review,"  July, 
1869.  Also,  Mr.  L.  H.  Morgan,  "A  Conjectural  Solution  of  the 
Origin  of  the  Class  System  of  Relationship,"  in  "  Proc.  American 
Acad,  of  Sciences,"  vol.  vii.  Feb.,  1868.  Prof.  Schaaffhausen 
("  Anthropolog.  Review,"  Oct.,  1869,  p.  373)  remarks  on  "  the  vestiges 
of  human  sacrifices  found  both  in  Homer  and  the  Old  Testament." 


164  THE  DESCENT  OF  MAN. 

nation,  as  the  same  author  asks,  can  be  named  that  was 
originally  monogamous?  The  primitive  idea  of  justice,  as 
shown  by  the  law  of  battle  and  other  customs  of  which  ves- 
tiges still  remain,  was  likewise  most  rude.  Many  existing 
superstitions  are  the  remnants  of  former  false  religious 
beliefs.  The  highest  form  of  religion — the  grand  idea  of 
God  hating  sin  and  loving  righteousness — was  unknown 
during  primeval  times. 

Turning  to  the  other  kind  of  evidence:  Sir  J.  Lubbock 
has  shown  that  some  savages  have  recently  improved  a  little 
in  some  of  their  simpler  arts.  From  the  extremely  curious 
account  which  he  gives  of  the  weapons,  tools  and  arts  in 
use  among  savages  in  various  parts  of  the  world  it  cannot 
be  doubted  that  these  have  nearly  all  been  independent  dis- 
coveries, excepting  perhaps  the  art  of  making  fire.*  The 
Australian  boomerang  is  a  good  instance  of  one  such  inde- 
pendent discovery.  The  Tahitians  when  first  visited  had 
advanced  in  many  respects  beyond  the  inhabitants  of  most 
of  the  other  Polynesian  islands.  There  are  no  just  grounds 
for  the  belief  that  the  high  culture  of  the  native  Peruvians 
and  Mexicans  was  derived  from  abroad  ;f  many  native 
plants  were  there  cultivated  and  a  few  native  animals 
domesticated.  We  should  bear  in  mind  that,  judging  from 
the  small  influence  of  most  missionaries,  a  wandering  crew 
from  some  semi-civilized  land,  if  washed  to  the  shores  of 
America,  would  not  have  produced  any  marked  effect  on 
the  natives  unless  they  had  already  become  somewhat  ad- 
vanced. Looking  to  a  very  remote  period  in  the  history  of 
the  world  we  find,  to  use  Sir  J.  Lubbock's  well-known 
terms,  a  paleolithic  and  neolithic  period;  and  no  one  will 
pretend  that  the  art  of  grinding  rough  flint  tools  was  a 
borrowed  one.  In  all  parts  of  Europe,  as  far  east  as 
Greece,  in  Palestine,  India,  Japan,  New  Zealand,  and 
Africa,  including  Egypt,  flint  tools  have  been  discovered 
in  abundance;  and  of  their  use  the  existing  inhabitants 
retain  no  tradition.  There  is  also  indirect  evidence  of 
their  former  use  by  the  Chinese  and  ancient  Jews.  Hence 
there  can  hardly  be  a  doubt  that  the  inhabitants  of  these 

*Sir  J.  Lubbock,  "Prehistoric  Times,"  2d  edit.,  1869,  chap,  xv 
and  xvi,  et  passim.  See  also  the  excellent  ninth  chapter  in  Tyler's 
*•  Early  History  of  Mankind,"  2d  edit.,  1870. 

f  Dr.  F.  Miiller  has  made  some  good  remarks  to  this  effect  in  the 
"  lieise  der  Novara:  Anthropolog.  Theil,"  Abtheil,  iii,  1868,  s.  12?. 


CIVILIZED  IfATIom.  165 

countries,  which  include  nearly  the  whole  civilized  world, 
were  once  in  a  barbarous  condition.  To  believe  that  man 
was  aboriginally  civilized  and  then  suffered  utter  degrada- 
tion in  so  many  regions  is  to  take  a  pitiably  low  view  of 
human  nature.  It  is  apparently  a  truer  and  more  cheerful 
view  that  progress  has  been  much  more  general  than  retro- 
gression; that  man  has  risen,  though  by  slow  and  inter- 
rupted steps,  from  a  lowly  condition  to  the  highest  standard 
as  yet  attained  by  him  in  knowledge,  morals  and  religion. 


l^e  mt!  MSGENf  Of  MAir, 


CHAPTER  YI. 

ON"  THE   AFFINITIES  AND   GENEALOGY   OF  MAN. 

Position  of  man  in  the  animal  series — The  natural  system  genea- 
logical—  Adaptive  characters  of  slight  value  —  Various  small 
points  of  resemblance  between  man  and  the  Quadrumana — Rank 
of  man  in  the  natural  system — Birthplace  and  antiquity  of  man — 
Absence  of  fossil  connecting  links — Lower  stages  in  the  geneal- 
ogy of  man,  as  inferred,  firstly  from  his  affinities  and  secondly 
from  his  structure — Early  androgynous  condition  of  the  verte- 
brata — Conclusion. 

Even  if  it  be  granted  that  the  difference  between  man 
and  his  nearest  allies  is  as  great  in  corporeal  structure  as 
some  naturalists  maintain^  and  although  we  must  grant  that 
the  difference  between  them  is  immense  in  mental  power, 
yet  the  facts  given  in  the  earlier  chapters  appear  to  declare, 
in  the  plainest  manner,  that  man  is  descended  from  some 
lower  form,  notwithstanding  that  connecting-links  have  not 
hitherto  been  discovered. 

Man  is  liable  to  numerous,  slight  and  diversified  varia- 
tions, which  are  induced  by  the  same  general  causes,  are 
governed  and  transmitted  in  accordance  with  the  same  gen- 
eral laws  as  in  the  lower  animals.  Man  has  multiplied  so 
rapidly  that  he  has  necessarily  been  exposed  to  struggle  for 
existence,  and  consequently  to  natural  selection.  He  has 
given  rise  to  many  races,  some  of  which  diff'er  so  much  from 
each  other,  that  they  have  often  been  ranked  by  naturalists 
as  distinct  species.  His  body  is  constructed  on  the  same 
homological  plan  as  that  of  other  mammals.  He  passes 
through  the  same  phases  of  embryological  development. 
He  retains  many  rudimentary  and  useless  structures,  which 
no  doubt  were  once  serviceable.  Characters  occasionally 
make  their  reappearance  in  him,  which  we  have  reason  to 
believe  were  possessed  by  his  early  progenitors.  If  the 
origin  of  man  had  been  wholly  different  from  that  of  all 
other  animals,  these  various  appearances  would  be  mere 
empty  deceptions ;  but  such  an  admission  is  incredible. 
These  appearances,  on  tlie  other  hand,  are  intelligible,  at 


APFtNtTtES  ANt>  OEITEALOQT.  let 

least  to  a  large  extent,  if  man  is  the  co-descendant  with 
other  mammals  of  some  unknown  and  lower  form. 

Some  naturalists,  from  being  deeply  impressed  with  the 
mental  and  spiritual  powers  of  man,  have  divided  the  whole 
organic  world  into  three  kingdoms,  the  Human,  the  Animal, 
and  the  Vegetable,  thus  giving  to  man  a  separate  kingdom.  * 
Spiritual  powers  cannot  be  compared  or  classed  by  the  nat- 
uralist; but  he  may  endeavor  to  show,  as  I  have  done,  that 
the  mental  faculties  of  man  and  the  lower  animals  do  not 
differ  in  kind,  although  immensely  in  degree.  A  difference 
in  degree,  however  great,  does  not  justify  us  in  placing  man 
in  a  distinct  kingdom,  as  will  perhaps  be  best  illustrated 
by  comparing  the  mental  powers  of  two  insects,  namely, 
a  coccus  or  scale-insect  and  an  ant,  which  undoubtedly  be- 
long to  the  same  class.  The  difference  is  here  greater  than, 
though  of  a  somewhat  different  kind  from,  that  between 
man  and  the  highest  mammal.  The  female  coccus,  while 
young,  attaches  itself  by  its  proboscis  to  a  plant;  sucks  the 
sap,  but  never  moves  again;  is  fertilized  and  lays  eggs;  and 
this  is  its  whole  history.  On  the  other  hand,  to  describe 
the  habits  and  mental  powers  of  worker  -  ants,  would 
require,  as  Pierre  Huber  has  shown,  a  large  volume;  I  may, 
however,  briefly  specify  a  few  points.  Ants  certainly  com- 
municate information  to  each  other,  and  several  unite  for 
the  same  work,  or  for  games  of  play.  They  recognize  their 
fellow-ants  after  months  of  absence,  and  feel  sympathy  for 
each  other.  They  build  great  edifices,  keep  them  clean, 
close  the  dooi*s  in  the  evening,  and  post  sentries.  They 
make  roads  as  well  as  tunnels  under  rivers,  and  temporary 
bridges  over  them,  by  clinging  together.  They  collect  food 
for  the  community,  and  when  an  object,  too  large  for 
entrance,  is  brought  to  the  nest,  they  enlarge  the  door,  and 
afterward  build  it  up  again.  They  store  up  seeds,  of  which 
they  prevent  the  germination,  and  which,  if  damp,  are 
brought  up  to  the  surface  to  dry.  They  keep  aphides  and 
other  insects  as  milch-cows.  They  go  out  to  battle  in  regu- 
lar bands,  and  freely  sacrifice  their  lives  for  the  common 
weal.  They  emigrate  according  to  a  preconcerted  plan. 
They  capture  slaves.  They  move  the  eggs  of  their  aphides, 
as  well  as  their  own  eggs  and  cocoons,  into  warm  parts  of 

♦Isidore  Geoffrey  St.-Hilaire  gives  a  detailed  account  of  the  posi- 
tion assigned  to  man  by  various  naturalists  in  tlieir  classifications: 
"Hist.  Nat.  Gen.,"  torn,  ii,  1859,  pp.  170-189. 


168  ^^^  t>E8Gt:NT  OP  MAN. 

the  nest,  in  order  that  they  may  be  quickly  hatched;  and 
endless  similar  facts  could  be  given.*  On  the  whole,  the 
difference  in  mental  power  between  an  ant  and  a  cocus  is 
immense;  yet  no  one  has  ever  dreamed  of  placing  these 
insects  in  distinct  classes,  much  less  in  distinct  kingdoms. 
No  doubt  the  difference  is  bridged  over  by  other  insects; 
and  this  is  not  the  case  with  man  and  the  higher  apes.  But 
we  have  every  reason  to  believe  that  the  breaks  in  the  series 
are  simply  the  results  of  many  forms  having  become 
extinct. 

Prof.  Owen,  relying  chiefly  on  the  structure  of  the  brain, 
has  divided  the  mammalian  series  into  four  sub-classes. 
One  of  these  he  devotes  to  man;  in  another  he  places  both 
the  Marsupials  and  the  Monotremata;  so  that  he  makes 
man  as  distinct  from  all  other  mammals  as  are  these  two 
latter  groups  conjoined.  This  view  has  not  been  accepted, 
as  far  as  I  am  aware,  by  any  naturalist  capable  of  forming 
an  independent  judgment,  and  therefore  need  not  here  be 
further  considered. 

We  can  understand  why  a  classification  founded  on  any 
single  character  or  organ — even  an  organ  so  wonderfully 
complex  and  important  as  the  brain — or  on  the  high  devel- 
opment of  the  mental  faculties,  is  almost  sure  to  prove 
unsatisfactory.  This  principle  has  indeed  been  tried  witli 
hymenopterous  insects;  but  when  thus  classed  by  their 
habits  or  instincts,  the  arrangement  proved  thoroughly  arti- 
ficial, f  Classifications  may,  of  course,  be  based  on  any 
character  whatever,  as  on  size,  color,  or  the  element  inhab- 
ited; but  naturalists  have  long  felt  a  profound  conviction 
that  there  is  a  natural  system.  This  system,  it  is  now  generally 
admitted,  must  be,  as  far  as  possible,  genealogical  in  arrange- 
ment— that  is,  the  co-descendants  of  the  same  form  must  be 
kept  together  in  one  group,  apart  from  the  co-descendants 
of  any  other  form;  but  if  the  parent-forms  are  related,  so 
will  be  their  descendants,  and  the  two  groups  together  will 
form  a  larger  group.  The  amount  of  ditt'erence  between 
the   several   groups — that  is,   the  amount  of  modification 

*  Some  of  the  most  interesting  facts  ever  published  on  the  habits 
of  ants  are  given  by  Mr.  Belt,  in  his  "  Naturalist  in  Nicaragua." 
1874.  See  also  Mr.  Moggridge's  admirable  work,  ''  Harvesting 
Ants,"  etc.,  1873,  also  "  L'Instinct  chez  les  Insectes,"  by  M.  George 
Pouchet,  "  Revue  des  Deux  Mondes,"  Feb.  1870,  p.  682. 

f  West  wood,  "  Modern  Class  of  Insects,"  vol.  ii.  1840,  p.  87. 


i 


AFFINITIES  AND  GENEALOGY.  169 

which  each  has  undergone — is  expressed  by  such  terms  as 
genera,  families,  orders  and  classes.  As  we  have  no  record 
of  the  lines  of  descent,  the  pedigree  can  be  discovered  only 
by  observing  the  degrees  of  resemblance  between  the  beings 
which  are  to  be  classed.  For  this  object  numerous  points 
of  resemblance  are  of  much  more  importance  than  the 
amount  of  similarity  or  dissimilarity  in  a  few  points.  If 
two  languages  were  found  to  resemble  each  other  in  a  multi- 
tude of  words  and  points  of  construction,  they  would  be 
universally  recognized  as  having  sprung  from  a  common 
source,  notwithstanding  that  they  differed  greatly  in  some 
few  words  or  points  of  construction.  But  with  organic 
beings  the  points  of  resemblance  must  not  consist  of  adapta- 
tions to  similar  habits  of  life;  two  animals  may,  for  instance, 
have  had  their  whole  frames  modified  for  living  in  the 
water,  and  yet  they  will  not  be  brought  any  nearer  to  each 
other  in  the  natural  system.  Hence  we  can  see  how  it  is 
that  resemblances  in  several  unimportant  structures,  in  use- 
less and  rudimentary  organs,  or  not  now  functionally  active, 
or  in  an  embryological  condition,  are  by  far  the  most  serv- 
iceable for  classification  ;  for  they  can  hardly  be  due  to 
adaptations  within  a  late  period;  and  thus  they  reveal  the 
old  lines  of  descent  or  of  true  affinity. 

We  can  further  see  why  a  great  amount  of  modification 
in  some  one  character  ought  not  to  lead  us  to  separate 
widely  any  two  organisms.  A  part  which  already  differs 
much  from  the  same  part  in  other  allied  forms  has  already, 
according  to  the  theory  of  evolution,  varied  much;  conse- 
quently it  would  (as  long  as  the  organism  remained  exposed 
to  the  same  exciting  conditions)  be  liable  to  further  varia- 
tions of  the  same  kind;  and  these,  if  beneficial,  would  be 
preserved,  and  thus  be  continually  augmented.  In  many 
cases  the  continued  development  of  a  part,  for  instance,  of 
the  beak  of  a  bird,  or  of  the  teeth  of  a  mammal,  would  not 
aid  the  species  in  gaining  its  food,  or  for  any  other  object; 
but  with  man  we  can  see  no  definite  limit  to  the  continued 
development  of  the  brain  and  mental  faculties,  as  far  as 
advantage  is  concerned.  Therefore  in  determining  the 
position  of  man  in  the  natural  or  genealogical  system  the 
extreme  development  of  his  brain  ought  not  to  out- 
weigh a  multitude  of  resemblances  in  other  less  important 
or  quite  unimportant  points. 

The  greater  number  of  naturalists  who  have  taken  into 


170  THE  DESCENT  OF  MAN. 

consideration  the  whole  structure  of  man,  including  his 
mental  faculties,  have  followed  Blumenbach  and  Cuvier, 
and  have  placed  man  in  a  separate  order,  under  the  title  of 
the  Bimana,  and  therefore  on  an  equality  with  the  orders  of 
the  Quadrumana,  Carnivora,  etc.  Recently  many  of  our 
best  naturalists  have  recurred  to  the  view  first  propounded 
by  Linnaeus,  so  remarkable  for  his  sagacity,  and  have  placed 
man  in  the  same  order  with  the  Quadruman,  under  the 
title  of  the  Primates.  The  justice  of  this  conclusion  will 
be  admitted;  for  in  the  first  place,  we  must  bear  in  mind 
the  comparative  insignificance  for  classification  of  the  great 
development  of  the  brain  in  man,  and  that  the  strongly- 
marked  differences  between  the  skulls  of  man  and  the 
Quadrumana  (lately  insisted  upon  by  Bischoff,  Aeby  and 
others)  apparently  follow  from  their  differently  developed 
brains.  In  the  second  place,  we  must  remember  that 
nearly  all  the  other  and  more  important  differences  between 
man  and  the  Quadrumana  are  manifestly  adaptive  in  their 
nature,  and  relate  chiefly  to  the  erect  position  of  man;  such 
as  the  structure  of  his  hand,  foot  and  pelvis,  the  curvature 
of  his  spine,  and  the  position  of  his  head.  The  family  of 
seals  offers  a  good  illustration  of  the  small  importance  of 
adaptive  characters  for  classification.  These  animals  differ 
from  all  other  Carnivora  in  the  form  of  their  bodies  and  in 
the  structure  of  their  limbs,  far  more  than  does  man  from 
the  higher  apes;  yet  in  most  systems,  from  that  of  Cuvier 
to  the  most  recent  one  by  Mr.  Flower,*  seals  are  ranked 
as  a  mere  family  in  the  order  of  the  Carnivora.  If  man 
had  not  been  his  own  classifier  he  would  never  have  thought 
of  founding  a  separate  order  for  his  own  reception. 

It  would  be  beyond  my  limits  and  quite  beyond  my 
knowledge  even  to  name  the  innumerable  points  of  struct- 
ure in  which  man  agrees  with  the  other  Primates.  Our 
great  anatomist  and  philosopher.  Prof.  Huxley,  has  fully 
discussed  this  subject,!  and  concludes  that  man  in  all  parts 
of  his  organization  differs  less  from  the  higher  apes  than 
these  do  from  the  lower  members  of  the  same  group.  Con- 
sequently there  "is  no  justification  for  placing  man  in  a 
distinct  order.'"' 

In  an  early  part  of  this  work  I  brought  forward  various 
facts,  showing  how  closely  man  agrees  in  constitution  with 

*  "  Proc.  Zoolog.  Soc,"  1863,  p.  4. 

\  "  Evidence  as  to  Man's  Place  in  Nature,"  1863,  p.  70,  et  passim. 


AFFINITIES  AND  GENEALOGY.  I7I 

the  higher  mammals;  and  this  agreement  must  depend  on 
our  close  similarity  in  minute  structure  and  chemical  com- 
position. I  gave,  as  instances,  our  liability  to  the  same  dis- 
eases and  to  the  attacks  of  allied  parasites;  our  tastes  in 
common  for  the  same  stimulants,  and  the  similar  effects 
produced  by  them,  as  well  as  by  various  drugs,  and  other 
such  facts. 

As  small,  unimportant  points  of  resemblance  between 
man  and  the  Quadrumana  are  not  commonly  noticed  in 
systematic  works,  and  as,  when  numerous,  they  clearly 
reveal  our  relationship,  I  will  specify  a  few  such  points. 
The  relative  position  of  our  features  is  manifestly  the  same; 
and  the  various  emotions  are  displayed  by  nearly  similar 
movements  of  the  muscles  and  skin,  chiefly  above  the  eye- 
brows and  round  the  mouth.  Some  few  expressions  are, 
indeed,  almost  the  same,  as  in  the  weeping  of  certain  kinds 
of  monkeys  and  in  the  laughing  noise  made  by  others, 
during  which  the  corners  of  the  mouth  are  drawn  back- 
ward and  the  lower  eye-lids  wrinkled.  The  external  ears 
are  curiously  alike.  In  man  the  nose  is  much  more  prom- 
inent than  in  most  monkeys;  but  we  may  trace  the  com- 
mencement of  an  aquiline  curvature  in  the  nose  of  the 
Hoolock  Gibbon;  and  this  in  the  Seinnopithecus  nasica  is 
carried  to  a  ridiculous  extreme. 

The  faces  of  many  monkeys  are  ornamented  with  beards, 
whiskers,  or  mustaches.  The  hair  on  the  head  grows  to 
a  great  length  in  some  species  of  Semnopithecus ;  *  and 
in  the  Bonnet  monkey  (Macacus  radiatus)  it  radiates  from 
a  point  on  the  crown,  with  a  parting  down  the  middle.  It 
is  commonly  said  that  the  forehead  gives  to  man  his  noble 
and  intellectual  appearance;  but  the  thick  hair  on  the  head 
of  the  Bonnet  monkey  terminates  downward  abruptly,  and 
is  succeeded  by  hair  so  short  and  fine  that  at  a  little  dis- 
tance the  forehead,  with  the  exception  of  the  eyebrows, 
appears  quite  naked.  It  has  been  erroneously  asserted  that 
eyebrows  are  not  present  in  any  monkey.  In  the  species 
just  named  the  degree  of  nakedness  of  the  forehead  differs  in 
different  individuals;  and  Eschrichtf  states  that  in  our  chil- 
dren the  limit  between  the  hairy  scalp  and  the  naked  fore- 
head is  sometimes  not  well  defined;  so  that  here  we  seem 

*lsid.  Geoffroy,  "Hist.  Nat.  Gen.,"  torn,  ii,  1859,  p.  217. 
f  ••  Ueber  die  Ricbtiing  der  Haare,"  etc,  Miiller's   "Archiv.  fUr 
Anat.  und  Phys.,"  1837,  s.  51. 


172  THE  DESCENT  OF  MAN. 

to  have  a  trifling  case  of  reversion  to  a  progenitor  in  whom 
the  forehead  had  not  as  yet  become  quite  naked. 

It  is  well  known  that  the  hair  on  our  arms  tends  to  con- 
verge from  above  and  below  to  a  point  at  the  elbow.  This 
curious  arrangement,  so  unlike  that  in  most  of  the  lower 
mammals,  is  common  to  the  gorrilla,  chimpanzee,  orang, 
some  species  of  Hylobates,  and  even  to  some  few  American 
monkeys.  But  in  Hylobates  agilis  the  hair  on  the  forearm 
is  directed  downward  or  toward  the  wrist  in  the  ordinary 
manner;  and  in  H.  lar  it  is  nearly  erect,  with  only  a  very 
slight  forward  inclination;  so  that  in  this  latter  species  it 
is  in  a  transitional  state.  It  can  hardly  be  doubted  that 
with  most  mammals  the  thickness  of  the  hair  on  the  back 
and  its  direction  is  adapted  to  throw  off  the  rain;  even  the 
transverse  hairs  on  the  fore  legs  of  a  dog  may  serve  for  this 
end  when  he  is  coiled  up  asleep.  Mr.  Wallace,  who  has 
carefully  studed  the  habits  of  the  orang,  remarks  that  the 
convergence  of  the  hair  toward  the  elbow  on  the  arms  of 
the  orang  may  be  explained  as  serving  to  throw  off  the 
rain,  for  this  animal  during  rainy  weather  sits  with  its 
arms  bent  and  with  the  hands  clasped  round  a  branch  or 
over  its  head.  According  to  Livingstone,  the  gorilla  also 
*^sits  in  pelting  rain  with  his  hands  over  his  head.^^*  If 
the  above  explanation  is  correct,  as  seems  probable,  the 
direction  of  the  hair  on  our  own  arms  offers  a  curious 
record  of  our  former  state;  for  no  one  supposes  that  it  is 
now  of  any  use  in  throwing  off  the  rain;  nor  in  our  present 
erect  condition  is  it  properly  directed  for  this  purpose. 

It  would,  however,  be  rash  to  trust  too  much  to  the 
principle  of  adaptation  in  regard  to  the  direction  of  the 
hair  in  man  or  his  early  progenitors;  for  it  is  impossible  to 
study  the  figures  given  by  Eschricht  of  the  arrangement  of 
the  hair  on  the  human  foetus  (this  being  the  same  as  in  the 
adult)  and  not  agree  with  this  excellent  observer  that  other 
and  more  complex  causes  have  intervened.  The  points  of 
convergence  seem  to  stand  in  some  relation  to  those  points 
in  the  embryo  which  are  last  closed  in  during  development. 
There  appears,  also,  to  exist  some  relation  between  the 
arrangement  of  the  hair  on  the  limbs  and  the  course  of  the 
medullary  arteries,  f 

*  Quoted  by  Reade,  "The  African  Sketch  Book,"  vol.  i,  1873,  p. 
152. 
f  On  the  hair  in  Hylobates,  see  "  Nat,  Hist,  of  Mammals,"  by  C.  L. 


AFFINITIES  AND  GENEALOGY,  173 

It  must  not  be  supposed  that  the  resemblances  between 
man  and  certain  apes  in  the  above  and  in  many  other 
points — sucli  as  in  having  a  naked  forehead,  long  tresses  on 
the  head,  etc. — are  all  necessarily  the  result  of  unbroken 
inheritance  from  a  common  progenitor,  or  of  subsequent 
reversion.  Many  of  these  resemblances  are  more  probably 
due  to  analogous  variation,  which  follows,  as  I  have  else- 
where attempted  to  show,*  from  co-descended  organisms 
having  a  similar  constitution,  and  having  been  acted  on  by 
like  causes  inducing  similar  modifications.  With  respect 
to  the  similar  direction  of  the  hair  on  the  forearms  of  man 
and  certain  monkeys,  as  this  character  is  common  to  almost 
all  the  anthropomorphous  apes,  it  may  probably  be  attribu- 
ted to  inheritance;  but  this  is  not  certain,  as  some  very 
distinct  American  monkeys  are  thus  characterized. 

Although,  as  we  have  now  seen,  man  has  no  just  right  to 
form  a  separate  Order  for  his  own  reception,  he  may  per- 
haps claim  a  distinct  sub-order  or  family.  Prof.  Huxley, 
in  his  last  work,f  divides  the  Primates  into  three  sub- 
orders; namely,  the  Anthropidag  with  man  alone,  the  Simi- 
adae,  including  monkeys  of  all  kinds,  and  the  Lemuridae 
with  the  diversified  genera  of  lemurs.  As  far  as  differ- 
ences in  certain  important  points  of  structure  are  concerned, 
man  may  no  doubt  rightly  claim  the  rank  of  a  sub-order; 
and  this  rank  is  too  low,  if  we  look  chiefly  to  his  mental 
faculties.  Nevertheless,  from  a  genealogical  point  of  view 
it  appears  that  this  rank  is  too  high,  and  that  man  ought 
to  form  merely  a  family,  or  possibly  even  only  a  sub- 
family. If  we  imagine  three  lines  of  descent  proceeding 
from  a  common  stock,  it  is  quite  conceivable  that  two  of 
them  might  after  the  lapse  of  ages  be  so  slightly  changed 
as  still  to  remain  a  species  of  the  same  genus,  while  the 
third  line  might  become  so  greatly  modified  as  to  deserve 
to  rank  as  a  distinct  sub-family,  family,  or  even  order. 
But   in  this  case  it  is  almost  certain  that  the  third  line 

Martin,  1841,  p.  415.  Also,  Isid.  Geoff roy  on  the  American  monkeys 
and  other  kinds,  "Hist.  Nat.  Gen.,"  vol.  ii,  1859,  pp.  216,  243, 
Eschricht,  ibid,  ss.  46,  55,  61.  Owen,  "  Anat.  of  Vertebrates,"  vol. 
iii,  p.  619.  Wallace,  "  Contributions  to  the  Theory  of  Natural  Selec- 
tion," 1870,  p.  344. 

*"  Origin  of  Species,"  5th  edit.,  1869,  p.  194.  "The  Variation  of 
Animals  and  Plants  under  Domestication,"  vol.  ii,  1868,  p.  348. 

f  "An  Introduction  to  the  Classification  of  Animals,"  1869,  p.  99. 


174  THE  DESCENT  OF  MAN. 

would  still  retain  through  inheritance  numerous  small 
points  of  resemblence  with  the  other  two.  Here,  then, 
would  occur  the  difficulty,  at  present  insoluble,  how  much 
weight  we  ought  to  assign  in  our  classifications  to  strongly- 
marked  differences  in  some  few  points — that  is,  to  the 
amount  of  modification  undergone,  and  how  much  to  close 
resemblance  in  numerous  unimportant  points,  as  indicating 
the  lines  of  descent  or  genealogy.  To  attach  much  weight 
to  the  few  but  strong  differences  is  the  most  obvious  and 
perhaps  the  safest  course,  though  it  appears  more  correct 
to  pay  great  attention  to  the  many  small  resemblances,  as 
giving  a  truly  natural  classification. 

In  forming  a  judgment  on  this  head  with  reference  to 
man,  we  must  glance  at  the  classification  of  the  Simiadae. 
This  family  is  divided  by  almost  all  naturalists  into  the 
Oatarrhine  group,  or  Old  World  monkeys,  all  of  which  are 
characterized  (as  their  name  expresses)  by  the  peculiar 
structure  of  their  nostrils,  and  by  having  four  premolars  in 
each  jaw;  and  into  the  Platyrrhine  group  or  New  World 
monkeys  (including  two  very  distinct  sub-groups),  all  of 
which  are  characterized  by  differently  constructed  nostrils 
and  by  having  six  premolars  in  each  jaw.  Some  other 
small  differences  might  be  mentioned.  Now  man  un- 
questionably belongs  in  his  dentition,  in  the  structure 
of  his  nostrils,  and  some  other  respects,  to  the  Catarrhine  or 
Old  World  division;  nor  does  he  resemble  the  Platyrrhines 
more  closely  than  the  Catarrhines  in  any  characters,  except- 
ing in  a  few  of  not  much  importance  and  apparently  of  an 
adaptive  nature.  It  is  therefore  against  all  probability  that 
some  New  World  species  should  have  formerly  varied  and 
produced  a  man-like  creature,  with  all  the  distinctive  char- 
acters proper  to  the  Old  World  division;  losing  at  the  same 
time  all  its  own  distinctive  characters.  There  can,  conse- 
quently, hardly  be  a  doubt  that  man  is  an  off-shoot  from 
the  Old  World  Simian  stem;  and  that  under  a  genealogical 
point  of  view  he  must  be  classed  with  the  Oatarrhine 
division.  * 

*  This  is  nearly  the  same  classification  as  that  provisionally 
adopted  by  Mr.  St.  George  Mivart  ("Transact.  Philosoph.  Soc," 
1867,  p.  300),  who,  after  separating  the  Lemuridse,  divides  the 
remainder  of  the  Primates  into  the  Hominidae,  the  Simiadae  which 
answer  to  the  Catarrhines,  the  Cebidae,  and  the  Hapalidse — these  two 
latter  groups  answering  to  the  Platyrrhines.  Mr.  Mivart  still  abides 
by  the  same  view;  see  "Nature,"  1871,  p.  481. 


AFFINITIES  AND  OKNEALOGT.  175 

The  anthropomorphous  apes,  namely,  the  gorilla,  chim- 
panzee, orang,  and  hylobates,  are  by  most  naturalists  sepa- 
rated from  the  other  Old  AVorld  monkeys,  as  a  distinct 
sub-group.  I  am  aware  that  Gratiolet,  relying  on  the 
structure  of  the  brain,  does  not  admit  the  existence  of  this 
sub-group,  and  no  doubt  it  is  a  broken  one.  Thus  the 
oi*ang,  as  Mr.  St.  Gr.  Mivart  remarks,*  ^*  is  one  of  the  most 
peculiar  and  aberrant  forms  to  be  found  in  the  order. ''^  The 
remaining  non-anthropomorphous  Old  World  monkeys  are 
again  divided  by  some  naturalists  into  two  or  three  smaller 
sub-groups ;  the  genus  Semnopithecus,  with  its  peculiar 
sacculated  stomach,  being  the  type  of  one  such  sub-group. 
But  it  appears  from  M.  Gaudry^s  wonderful  discoveries  in 
Attica  that  during  the  Miocene  period  a  form  existed  there 
which  connected  Semnopithecus  and  Macacus ;  and  this 
probably  illustrates  the  manner  in  which  the  other  and 
higher  groups  were  once  blended  together. 

If  the  anthropomorphous  apes  be  admitted  to  form  a 
natural  sub-group,  then  as  man  agrees  with  them  not  only 
in  all  those  characters  which  he  possesses  in  common  with 
the  whole  Catarrhine  group, but  in  other  peculiar  characters, 
such  as  the  absence  of  a  tail  and  of  callosities,  and  in  gen- 
eral appearance,  we  may  infer  that  some  ancient  member  of 
the  anthropomorphous  sub-group  gave  birth  to  man.  It  is 
not  probable  that,  through  the  law  of  analogous  variation, 
a  member  of  one  of  the  other  lower  sub-groups  should  have 
given  rise  to  a  man-like  creature  resembling  the  higher 
anthropomorphous  apes  in  so  many  respects.  Iso  doubt 
man,  in  comparison  with  most  of  his  allies,  has  undergone 
an  extraordinary  amount  of  modification,  chiefly  in  conse- 
quence of  the  great  development  of  his  brain  and  his  erect 
position;  nevertheless,  we  should  bear  in  mind  that  he  ^'^is 
but  one  of  several  exceptional  forms  of  Primates."  \ 

Every  natumlist  who  believes  in  the  principle  of  evolu- 
tion will  grant  that  the  two  main  divisions  of  the  Simiadae, 
namely,  the  Catarrhine  and  Platyrrhine  monkeys,  with  their 
sub-groups,  have  all  proceeded  from  some  one  extremely 
ancient  progenitor.  The  early  descendants  of  this  progen- 
itor, before  they  had  diverged  to  any  considerable  extent 
from  each  other,  would  still  have  formed  a  single  natural 

*  "  Transact.  Zoolog.  Soc.,"  vol.  vi,  1867,  p.  214. 

f  Mr.  St.  G.  Mivart,  ''Transact.  Phil.  Soc.,"  1867,  p.  410, 


17G  THB  DESCENT  OF  MAN, 

group;  but  some  of  the  species  or  incipient  genera  would 
litive  already  begun  to  indicate  by  their  diverging  characters 
the  future  distinctive  marks  of  the  Catarrhine  and 
Platyrrliine  divisions.  Hence  the  members  of  this  su2)posed 
ancient  group  would  not  have  been  so  uniform  in  their 
dentition,  or  in  the  structure  of  tlieir  nostrils,  as  are  the 
existing  Catarrhine  monkeys  in  oneway  and  the  Platyrrhines 
in  another  way,  but  would  have  resembled  in  this  respect 
the  allied  Lemuridas,  which  differ  greatly  from  each  other 
in  the  form  of  their  muzzles,*  and  to  an  extraordinary 
degree  in  their  dentition. 

Tlie  Catarrhine  and  Platyrrliine  monkeys  agree  in  a.multi- 
tude  of  cliaracters,  as  is  shown  by  their  unquestionably 
belonging  to  one  and  the  same  order.  The  many  charac- 
ters which  they  possess  in  common  can  hardly  have  been 
independently  acquired  by  so  many  distinct  species;  so  that 
these  characters  must  have  been  inherited.  But  a  naturalist 
would  undoubtedly  have  ranked  as  an  ape  or  a  monkey,  an 
ancient  form  Avhich  possessed  many  characters  common  to 
the  Catarrhine  and  Platyrrliine  monkeys,  other  characters  in 
an  intermediate  condition,  and  some  few,  perhaps,  distinct 
from  those  now  found  in  either  group.  And  as  man  from 
a  genealogical  point  of  view  belongs  to  the  Catarrhine  or  Old 
World  stock,  we  must  conclude,  however  much  the  conclu- 
sion may  revolt  our  pride,  that  our  early  progenitors  would 
have  been  properly  thus  designated.!  But  we  must  not 
fall  into  the  error  of  supposing  that  the  early  progenitor  of 
the  whole  Simian  stock,  including  man,  was  identical 
with,  or  even  closely  resembled,  any  existing  ape  or  monkey. 

On  the  Birthplace  and  Antiquity  of  Man. — We  are 
naturally  led  to  inquire,  where  was  the  birthplace  of  man 
at  that  stage  of  descent  when  our  progenitors  diverged  from 
the  Catarrhine  stock?  The  fact  that  they  belonged  to  this 
stock  clearly  shows  that  they  inhabitated  the  Old  World; 
but  not  Australia  nor  any  oceanic  island,  as  we  may  infer 

*  Messrs.  Murie  and  Mivart  on  the  Lemuroidea,  "  Transact.  Zoolog. 
Soc,"  vol.  vii.  1869,  p.  5. 

fHackel  has  come  to  this  same  conclusion.  See  "  Ueber  die 
Entstehung  des  Menschengeschlechts,"  in  Virchow's  "  Sammlung. 
gemein.  wissen.  Vortrage,"  1868,  s.  61.  Also  his  "  Naturliche  Schop- 
fungsgeschichte,"  1868,  in  which  he  gives  in  detail  his  views  on  the 
genealogy  of  man. 


AFFINITIES  AND  OENEALOG  F.  177 

from  tlie  laws  of  geographical  distribution.  In  each  great 
region  of  the  world  the  living  mammals  are  closely  related 
to  the  extinct  species  of  the  siime  region.  It  is,  therefore, 
probable  that  Africa  was  formerly  inhabited  by  extinct  apes 
closely  allied  to  the  gorilla  and  chimpanzee;  and  as  these 
two  species  are  now  man's  nearest  allies,  it  is  somewhat 
more  probable  that  our  early  progenitors  lived  on  the 
African  continent  than  elsewhere.  But  it  is  useless  to 
speculate  on  this  subject;  for  two  or  three  anthropomor- 
phous apes,  one  the  Dryopithecus  *  of  Lartet,  nearly  as 
large  as  a  man,  and  closely  allied  to  Hylobates,  existed  in 
Europe  during  the  Miocene  age;  and  since  so  remote  a 
period  the  earth  has  certainly  undergone  many  great  revo- 
lutions, and  there  has  been  ample  time  for  migration  on  the 
largest  scale. 

At  the  period  and  place,  whenever  and  wherever  it  was, 
when  man  first  lost  his  hairy  covering,  he  probably 
inhabited  a  hot  country;  a  circumstance  favorable  for 
the  frugiferous  diet  on  which,  judging  from  analogy, 
he  subsisted.  We  are  far  from  knowing  how  long  ago 
it  was  when  man  first  diverged  from  the.  Catarrhine  stock; 
but  it  may  have  occurred  at  an  epoch  as  remote  as  the 
Eocene  period;  for  that  the  higher  apes  had  diverged  from 
the  lower  apes  as  early  as  the  Upper  Miocene  period  is 
shown  by  the  existence  of  the  Dryopithecus.  We  are  also 
quite  ignorant  at  how  rapid  a  rate  organisms,  Vhether  high 
or  low  in  the  scale,  may  be  modified  under  favorable  cir- 
cumstances; we  know,  however,  that  some  have  retained 
the  same  form  during  an  enormous  lapse  of  time.  From 
what  we  see  going  on  under  domestication  we  learn  that 
some  of  the  co-descendants  of  the  same  species  may  be  not 
at  all,  some  a  little,  and  some  greatly  changed,  all  within 
the  same  period.  Thus  it  may  have  been  wdth  man,  who 
has  undergone  a  great  amount  of  modification  in  certain 
characters  in  comparison  with  the  higher  apes. 

The  great  break  in  the  organic  chain  between  man  and 
his  nearest  allies,  which  cannot  be  bridged  over  by  any  ex- 
tinct or  living  species,  has  often  been  advanced  as  a  grave 
objection  to  the  belief  that  man  is  descended  from  some 
lower  form;  but  this  objection  will  not  appear  of  much 

*Dr.  C.  Forsyth  Major,  "  Sur  les  Singes  Fossiles  trouves  en 
Jtalie:  "  Soc.  Ital.  des  Sc.  Nat.,"  torn,  xv,  1872. 


178  THE  DESCENT  OF  MAN. 

weight  to  those  who,  from  general  reasons,  believe  in  the 
general  principle  of  evolution.  Breaks  often  occur  in  all 
parts  of  the  series,  some  being  wide,  sharp  and  defined, 
others  less  so  in  various  degrees;  as  between  the  orang  and 
its  nearest  allies  —  between  the  Tarsius  and  the  other 
Lemuridai — between  the  elephant,  and  in  a  more  striking 
manner  between  the  Ornithorhynchus  or  Echidna,  and  all 
other  mammals.  But  these  breaks  depend  merely  on  tlie 
number  of  related  forms  which  have  become  extinct.  At 
some  future  period,  not  very  distant  as  measured  by  cent- 
uries, the  civilized  races  of  man  will  almost  certainly  ex- 
terminate and  replace  the  savage  races  throughout  the 
world.  At  the  same  time  the  anthropomorphous  apes,  as 
Prof.  Schiiaffhausen  has  remarked,*  will  no  doubt  be  ex- 
terminated. The  break  between  man  and  his  nearest  allies 
will  then  be  wider,  for  it  will  intervene  between  man  in  a 
more  civilized  state,  as  we  may  hope,  even  than  the  Cauca- 
sian, and  some  ape  as  low  as  a  baboon,  instead  of  as  now 
between  the  negro  or  Australian  and  the  gorilla. 

With  respect  to  the  absence  of  fossil  remains  serving  to 
connect  man  with  his  ape-like  progenitors,  no  one  will  lay 
much  stress  on  this  fact  who  reads  Sir  C.  LyelFs  discus- 
sion,! where  he  shows  that  in  all  the  vertebrate  classes  the 
discovery  of  fossil  remains  has  been  a  very  slow  and  fortuit- 
ous process.  Nor  should  it  be  forgotten  that  those  regions 
which  are  the  most  likely  to  afford  remains  connecting  man 
with  some  extinct  ape-like  creature  have  not  as  yet  been 
searched  by  geologists. 

Lotver  Stages  in  the  Genealogy  of  Man. — We  have  seen 
tliat  man  appears  to  have  diverged  from  the  Catarrhine  or 
Old  World  division  of  the  Simiadae  after  these  had  diverged 
from  the  New  World  division.  We  will  now  endeavor  to 
follow  the  remote  traces  of  his  genealogy,  trusting  princi- 
pally to  the  mutual  affinities  between  the  various  classes 
and  orders,  with  some  slight  reference  to  the  periods,  as 
far  as  ascertained,  of  their  successive  appearance  on  the 
earth.  The  Lemuridae  stand  below  and  near  to  the  Simiadae, 
and  constitute  a  very  distinct  family  of  the  Primates,  or, 
according  to  Hackel  and  others,  a  distinct  order.     This 

*  "  Anthropological  Review,"  April,  1867,  p.  286. 
f "  Elements   of    Geology,"   1865,    pp.    583-585.     "Antiquity    of 
Man,"  1863,  p.  145. 


AFFINITIES  AND  GENEALOGY,  179 

group  is  diversified  and  broken  to  an  extraordinary  degree, 
and  includes  many  aberrant  forms.  It  has,  therefore,  proba- 
bly suffered  much  extinction.  Most  of  the  remnants  sur- 
vive on  islands,  such  as  Madagascar  and  the  Malaya  Anrchi- 
pelago,  where  they  have  not  been  exposed  to  so  severe  a 
competition  as  they  would  have  been  on  well-stocked  con- 
tinents. This  group  likewise  presents  many  gradations, 
leading,  as  Huxley  remarks,*  "insensibly  from  the  crown 
and  summit  of  the  animal  creation  down  to  creatures 
from  which  there  is  but  a  step,  as  it  seems,  to  the  lowest, 
smallest  and  the  least  intelligent  of  the  placental  mam- 
malia." From  these  various  considerations  it  is  probable 
that  the  Simiadae  were  originally  developed  from  the  pro- 
genitors of  the  existing  Lemuridae;  and  these  in  their  turn 
from  forms  standing  very  low  in  the  mammalian  series. 

The  Marsupials  stand  in  many  important  characters 
below  the  placental  mammals.  They  appeared  at  an 
earlier  geological  period,  and  their  range  was  formerly 
much  more  extensive  than  at  present.  Hence  the  Placen- 
tata  are  generally  supposed  to  have  been  derived  from  the 
Implacentata  or  Marsupials ;  not,  however,  from  forms 
closely  resembling  the  existing  Marsupials,  but  from  their 
early  progenitors.  The  Monotremata  are  plainly  allied  to 
the  Marsupials,  forming  a  third  and  still  lower  division  in 
the  great  mammalian  series.  They  are  represented  at  the 
present  day  solely  by  the  Omithorhynchus  and  Echidna; 
and  these  two  forms  may  be  safely  considered  as  relics  of  a 
much  larger  group,  representatives  of  which  have  been  pre- 
served in  Australia,  through  some  favorable  concurrence  of 
circumstances.  The  Monotremata  are  eminently  interesting, 
as  leading  in  several  important  points  of  structure  toward 
the  class  of  reptiles. 

In  attempting  to  trace  the  genealogy  of  the  mammalia, 
and  therefore  of  man,  lower  down  in  the  series,  we  become 
involved  in  greater  and  greater  obscurity;  but  as  a  most 
capable  judge,  Mr.  Parker,  has  remarked,  we  have  good 
reason  to  believe,  that  no  true  bird  or  reptile  intervenes  in 
the  direct  line  of  descent.  He  who  wishes  to  see  what 
ingenuity  and  knowledge  can  effect,  may  consult  Prof. 
Hackel's  works. f    I  will  content  myself  with  a  few  general 

*"  Man's  Place  in  Nature,"  p.  105. 

f  Elaborate  tables  are  given  in  bis  "  Generelle  Morpbologie  "  (B. 
ii,  s.  153  and  s,  425);  and  witb  more  especial  reference  to  man  in  bis 


180  THE  DESCENT  OF  MAN. 

remarks.  Every  evolutionist  will  admit  that  the  five  great 
vertebrate  classes,  namely,  mammals,  birds,  reptiles,  amphib- 
ians and  fishes,  are  descended  from  some  one  prototype;  for 
they  have  much  in  common,  especially  during  their  embry- 
onic state.  As  the  class  of  fishes  is  the  most  lowly  organ- 
ized, and  appeared  before  the  others,  we  may  conclude  that 
all  the  members  of  the  vertebrate  kingdom  are  derived 
from  some  fish-like  animal.  The  belief  that  animals  so 
distinct  as  a  monkey,  an  elephant,  a  humming-bird,  a 
snake,  a  frog,  and  a  fish,  etc.,  could  all  have  sprung  from 
the  same  parents,  will  appear  monstrous  to  those  who  have 
not  attended  to  the  recent  progress  of  natural  history.  For 
this  belief  implies  the  former  existence  of  links  binding 
closely  together  all  these  forms,  now  so  utterly  unlike. 

Nevertheless,  it  is  certain  that  groups  of  animals  have 
existed,  or  do  now  exist,  which  serve  to  connect  several  of 
the  great  vertebrate  classes  more  or  less  closely.  We  have 
seen  that  the  Ornithorhynchus  graduates  toward  reptiles; 
and  Prof.  Huxley  has  discovered,  and  is  confirmed  by  Mr. 
Cope  and  others,  that  the  Dinosaurians  are  in  many  impor- 
tant characters  intermediate  between  certain  reptiles  and 
certain  birds — the  birds  referred  to  being,  the  ostrich  tribe 
(itself  evidently  a  widely-diffused  remnant  of  a  larger 
group)  and  the  Archeopteryx,  that  strange  Secondary  bird, 
Avith  a  long  lizard-like  tail.  Again,  according  to  Prof. 
Owen,*  the  Ichthyosaurians — great  sea-lizards  furnished 
with  paddles — present  many  affinities  with  fishes,  or  rather 
according  to  Huxley,  with  amphibians ;  a  class  which, 
including  in  its  highest  division  frogs  and  toads,  is  plainly 
allied  to  the  Ganoid  fishes.  These  latter  fishes  swarmed 
during  the  earlier  geological  periods,  and  were  constructed 
on  what  is  called  a  generalized  type,  that  is,  they  presented 
diversified  affinities  with  other  groups  of  organisms.  The 
Lepidosiren  is  also  so  closely  allied  to  amphibians  and 
fishes,  that  naturalists  long  disputed  in  which  of  these  two 
classes  to  rank  it;  it,  and  also  some  few  Ganoid  fishes,  have 

"  Nattirliclie  ScliSpfungsgeschiclite,"  1868.  Prof.  Huxley,  in  review- 
ing this  latter  work  ("  The  Academy,"  1869,  p.  42)  says,  that  he  con- 
siders the  phylum  or  lines  of  descent  of  the  vertebrata  to  be  admir- 
ably discussed  by  Hackel,  although  he  differs  on  some  points.  He 
expresses,  also,  his  high  estimate  of  the  general  tenor  and  spirit  of 
the  whole  work. 
*"  Palaeontology, "  1860,  p.  199. 


AFFINITIES  AND  GENEALOat.  181 

been  preserved  from  utter  extinction  by  inhabiting  rivers, 
which  are  harbors  of  refuge,  and  are  related  to  the  great 
waters  of  the  ocean  in  the  same  way  that  islands  are  to 
continents. 

Lastly,  one  single  member  of  the  immense  and  diversi- 
fied class  of  fishes,  namely,  the  lancelet  or  amphioxus,  is  so 
different  from  all  other  fishes,  that  Hackel  maintains  that 
it  ought  to  form  a  distinct  class  in  the  vertebrate  kingdom. 
This  fish  is  remarkable  for  its  negative  characters;  it  can 
hardly  be  said  to  possess  a  brain,  vertebral  column,  or  heart, 
etc. ;  so  that  it  was  classed  by  the  older  naturalists  among 
the  worms.  Many  years  ago  Prof.  Goodsir  perceived  that 
the  lancelet  presented  some  affinities  with  the  Ascidians, 
which  are  invertebrate,  hermaphrodite,  marine  creatures 
permanently  attached  to  a  support.  They  hardly  appear 
like  animals  and  consist  of  a  simple,  tough,  leathery  sack, 
with  two  small  projecting  orifices.  They  belong  to  the 
MuUuscoida  of  Huxley — a  lower  division  of  the  great  king- 
dom of  the  Mollusca;  hut  they  have  recently  been  placed 
by  some  naturalists  among  the  Vermes  or  worms.  Their 
larvae  somewhat  resemble  tadpoles  in  shape,*  and  have  the 
power  of  swimming  freely  about.  M.  Kovalevsky  f  has 
lately  observed  that  the  larvae  of  Ascidians  are  related  to 
the  vertebrata,  in  their  manner  of  development,  in  the 
relative  position  of  the  nervous  system,  and  in  possessing  a 
structure  closely  like  the  chorda  dorsalis  of  vertabrate  ani- 
mals ;  and  in  this  he  has  been  since  confirmed  by 
Prof.  Kupffer.  M.  Kovalevsky  writes  to  me  from 
Xaples,  that  he  has  now  carried  these  observations  yet  fur- 
ther, and  should  his  results  be  well  established,  the  whole 
will  form  a  discovery  of  the  very  greatest  value.  Thus,  if 
we  may  rely  on  embryology,  ever  the  safest  guide  in  classi- 

*  At  the  Falkland  Islands  I  had  the  satisfaction  of  seeing,  in  April, 
1833,  and  therefore  some  years  before  any  other  naturalist,  the  loco- 
motive larvae  of  a  compound  Ascidian,  closely  allied  to  Synoicum, 
but  apparently  generically  distinct  from  it.  The  tail  was  about  five 
times  as  long  as  the  oblong  head,  and  terminated  in  a  very  fine  fila- 
ment. It  was,  as  sketched  by  me  under  a  simple  microscope,  plainly 
divided  by  transverse  opaque  partitions,  which  I  presume  represent 
the  great  cells  figured  by  Kovalevsky.  At  an  early  stage  of  develop- 
ment the  tail  was  closely  coiled  round  the  head  of  the  larva. 

f  "  Memoires  de  I'Acad.  des  Sciences  de  St.  Petersbourg,"  torn,  x, 
Nu.  15,  1866. 


182  ^-^^  DESCENT  Ot"  MAN. 

fication,  it  seems  that  we  have  at  last  gained  a  clew  to  the 
source  whence  the  vertebrata  were  derived.*  We  should 
then  be  justified  in  believing  that  at  an  extremely  remote 
period  a  group  of  animals  existed  resembling  in  many 
respects  the  larvae  of  our  present  Ascidians,  which  diverged 
into  two  great  branches — the  one  retrograding  in  develop- 
ment and  producing  the  present  class  of  Ascidians,  the 
other  rising  to  the  crown  and  summit  of  the  animal  king- 
dom by  giving  birth  to  the  vertebrata. 

We  have  thus  far  endeavored  rudely  to  trace  the  geneal- 
ogy of  the  vertebrata  by  the  aid  of  their  mutual  affinities. 
We  will  now  look  to  man  as  he  exists;  and  we  shall,  I  think, 
be  able  partially  to  restore  the  structure  of  our  early  pro- 
genitors, during  successive  periods,  but  not  in  due  order  of 
time.  This  can  be  effected  by  means  of  the  rudiments 
which  man  still  retains,  by  the  characters  which  occasion- 
ally make  their  appearance  in  him  through  reversion,  and 
by  the  aid  of  the  principles  of  morphology  and  embryology. 
The  various  facts,  to  which  I  shall  here  allude,  have  been 
given  in  the  previous  chapters. 

The  early  progenitors  of  man  must  have  been  once  cov- 
ered with  hair,  both  sexes  having  beards;  their  ears  were 
probably  pointed  and  capable  of  movement ;  and  their 
bodies  were  provided  with  a  tail,  having  the  proper  muscles. 
Their  limbs  and  bodies  were  also  acted  on  by  many  mus- 
cles which  now  only  occasionally  reappear,  but  are  normally 
present  in  the  Quadrumana.  At  this  or  some  earlier  period 
the  great  artery  and  nerve  of  the  humerus  ran  through  a 
supracondyloid  foramen.  The  intestine  gave  forth  a  much 
larger  diverticulum  or  caecum  than  that  now  existing.  The 
foot  was  then  prehensile,  judging  from  the  condition  of  the 
great  toe  in  the  foetus;  and  our  progenitors,  no  doubt,  were 
arboreal  in  their  habits,  and  frequented  some  warm,  forest- 
clad  land.     The  males  had  great  canine  teeth,  which  served 

*But  I  am  bound  to  add  that  some  competent  judges  dispute  this 
conclusion;  for  instance,  M.  Giard,  in  a  series  of  papers  in  the 
"  Archives  de  Zoologie  Experimentale,"  for  1872.  Nevertheless,  this 
naturalist  remarks,  p.  281,  ''  L'organization  de  la  larve  ascidienne  en 
dehors  de  toute  hypothese  et  de  toute  theorie,  nous  montre  comment 
la  nature  pent  produire  la  disposition  fondamentale  du  type  vf.  tebre 
(I'existence  d'une  corde  dorsale)  chez  un  invertebre  par  la  seu'e  con- 
dition vitale  de  I'adaptation,  et  cette  simple  possibilite  du  p»>ssage 
supprime  I'abime  entre  les  deux  sous-regnes,  encore  bien  bu'eu  ignore 
par  ou  le  passage  s'est  fait  en  realite," 


AFFINITIES  AND  GENEALOGY.  183 

them  as  formidable  weapons.  At  a  much  earlier  period  the 
uterus  was  double ;  the  excreta  were  voided  through  a 
cloaca;  and  the  eye  was  protected  by  a  third  eye-lid  or  nic- 
titating membrane.  At  a  still  earlier  period  the  progenitors 
of  man  must  have  been  aquatic  in  their  habits;  for  morphology 
plainly  tells  us  that  our  lungs  consist  of  a  modified  swim- 
bladder,  which  once  served  as  a  float.  The  clefts  on  the 
neck  in  the  embryo  of  man  show  where  the  branchiae  once 
existed.  In  the  lunar  or  weekly  recurrent  periods  of  some 
of  our  functions  we  apparently  still  retain  traces  of  our 
primordial  birth-place,  a  shore  washed  by  the  tides.  At 
about  this  same  early  period  the  true  kidneys  were  replaced 
by  the  coi-pora  wolffiana.  The  heart  existed  as  a  simple 
pulsating  vessel;  and  the  chorda  dorsalis  took  the  place  of 
a  vertebral  column.  These  early  ancestors  of  man,  thus 
seen  in  the  dim  recesses  of  time,  must  have  been  as  simply, 
or  even  still  more  simply,  organized  than  the  lancelet  or 
amphioxus. 

There  is  one  other  point  deserving  a  fuller  notice.  It 
has  long  been  known  that  in  the  vertebrate  kingdom  one 
sex  bears  rudiments  of  various  accessory  parts,  appertain- 
ing to  the  reproductive  system,  which  properly  belong  to 
the  opposite  sex;  and  it  has  now  been  ascertained  that  at  a 
very  early  embryonic  period  both  sexes  possessed  true  male 
and  female  glands.  Hence  some  remote  progenitor  of  the 
whole  vertebrate  kingdom  appears  to  have  been  hermaph- 
rodite or  androgynous.*  But  here  we  encounter  a  singu- 
lar difficulty.  In  the  mammalian  class  the  males  possess 
rudiments  of  a  uterus  with  the  adjacent  passage,  in  their 
vesiculae  prostaticae;  they  bear  also  rudiments  of  mammae, 
and  some  male  Marsupials  have  traces  of  a  marsupial  sack.  \ 
Other  analogous  facts  could  be  added.  Are  we,  then,  to 
suppose  that  some  extremely  ancient  mammal  continued 

♦This  is  the  conclusion  of  Prof.  Gegenbaur,  one  of  the  highest 
authorities  in  comparative  anatomy;  see  "  Grundziige  der  vergleich. 
Anat.,"  1870,  s.  876.  The  result  has  been  arrived  at  chiefly  from  the 
study  of  the  Amphibia;  but  it  appears  from  the  researches  of  Wald- 
eyer  (as  quoted  in  "  Journal  of  Anat.  and  Phys.."  1869,  p.  161),  that 
the  sexual  organs  of  even  ' '  the  higher  vertebrata  are  in  their  early 
condition  hermaphrodite."  Similar  views  have  long  been  held  by 
sf)me  authors,  though  until  recently  without  a  firm  basis. 

f  The  male  Thylacinus  offers  the  best  instance.  Owen,  "  Anatomy 
of  Vertebrates,"  vol.  iii,  p.  771. 


184  THE  DESCENT  OF  MAN.      * 

androgynous,  after  it  had  acquired  the  chief  distinctions  of 
its  class,  and,  therefore,  after  it  had  diverged  from  the 
lower  classes  of  the  vertebrate  kingdom?  This  seems  very 
improbable,  for  we  have  to  look  to  fishes,  the  lowest  of  all 
the  classes,  to  find  any  still  existent  androgynous  forms.* 
That  various  accessory  parts,  proper  to  each  sex,  are  found 
in  a  rudimentary  condition  in  the  opposite  sex,  may  be 
explained  by  such  organs  having  been  gradually  acquired 
by  the  one  sex,  and  then  transmitted  in  a  more  or  less 
imperfect  state  to  the  other.  When  we  treat  of  sexual 
selection  we  shall  meet  with  innumerable  instances  of  this 
form  of  transmission — as  in  the  case  of  the  spurs,  plumes, 
and  brilliant  colors,  acquired  for  battle  or  ornament  by 
male  birds  and  inherited  by  the  females  in  an  imperfect  or 
rudimentary  condition. 

The  possession  by  male  mammals  of  functionally  imper- 
fect mammary  organs  is,  in  some  respects,  especially 
curious.  The  Monotremata  have  the  proper  milk-secreting 
glands  with  orifices,  but  no  nipples;  and  as  these  animals 
stand  at  the  very  base  of  the  mammalian  series,  it  is  proba- 
ble that  the  progenitors  of  the  class  also  had  milk-secreting 
glands,  but  no  nipples.  This  conclusion  is  supported  by 
what  is  known  of  their  manner  of  development;  for  Prof. 
Turner  informs  me,  on  the  authority  of  Kolliker  and 
Langer,  that  in  the  embryo  the  mammary  glands  can  be 
distinctly  traced  before  the  nipples  are  in  the  least  visible; 
and  the  development  of  successive  parts  in  the  individual 
generally  represents  and  accords  with  the  development  of 
successive  beings  in  the  same  line  of  descent.  The  Mar- 
supials diifer  from  the  Monotremata  by  possessing  nipples; 
so  that  probably  these  organs  were  first  acquired  by  the 
Marsupials,  after  they  had  diverged  from,  and  risen  above, 
the    Monotremata,   and    were    then    transmitted    to  the 

*  Hermapliroditism  has  been  observed  in  several  species  of  Ser- 
ranus,  as  well  as  in  some  other  fishes,  where  it  is  either  normal  and 
symmetrical,  or  abnormal  and  unilateral.  Dr.  Zouteveen  has  given 
me  references  on  this  subject,  more  especially  to  a  paper  by  Prof. 
Halbertsma,  in  the  "Transact,  of  the  Dutch  Acad,  of  Sciences,"  vol. 
xvi.  Dr.  GUnther  doubts  the  fact,  but  it  has  now  been  recorded  by 
too  many  good  observers  to  be  any  longer  disputed.  Dr.  M.  Lessona 
writes  to  me  that  he  has  verifit^d  the  observations  made  by  Cavolini 
on  Serranus.  Prof.  Ercolaui  has  recently  shown  ("  Accad.  delle 
Scienze,"  Bologna,  Dec.  28,  1871)  that  eels  are  androgynous. 


AFFINITIES  AND  GENEALOGY.  185 

placental  mammals.*  No  one  will  suppose  that  the  Mar- 
supials still  remained  androgynous  after  they  had  approx- 
imately acquired  their  present  structure.  How  then  are 
we  to  account  for  male  mammals  possessing  mammae?  It 
is  possible  that  they  were  first  developed  in  the  females  and 
then  transferred  to  the  males,  but  from  what  follows  this  is 
hardly  probable. 

It  may  be  suggested,  as  another  view,  that  long  after  the 
progenitors  of  the  whole  mammalian  class  had  ceased  to  be 
androgynous,  both  sexes  yielded  milk,  and  thus  nourished 
their  young;  and  in  the  case  of  the  Marsupials,  that  both 
sexes  carried  their  young  marsupial  sacks.  This  will  not 
appear  altogether  improbable,  if  we  reflect  that  the  males 
of  existing  syngnathous  fishes  receive  the  eggs  of  the 
females  in  their  abdominal  pouches,  hatch  them,  and  after- 
ward, as  some  believe,  nourish  the  young;  \  that  certain 
other  male  fishes  hatch  the  eggs  within  their  mouths  or 
branchial  cavities;  that  certain  male  toads  take  the  chaplets 
of  eggs  from  the  females  and  wind  them  round  their  own 
thighs,  keeping  them  there  until  the  tadpoles  are  born; 
that  certain  male  birds  undertake  the  whole  duty  of  incuba- 
tion, and  that  male  pigeons,  as  well  as  the  females,  feed 
their  nestlings  with  a  secretion  from  their  crops.  But  the 
above  suggestion  first  occurred  to  me  from  the  mammary 
glands  of  male  mammals  being  so  much  more  perfectly 
developed  than  the  rudiments  of  the  other  accessory  repro- 
ductive parts,  which  are  found  in  the  one  sex  though  proper 
to  the  other.  The  mammary  glands  and  nipples,  as  they 
exist  in  male  mammals,  can  indeed  hardly  be  called  rudiment- 
ary; they  are  merely  not  fully  developed  and  not  functionally 

*Prof.  Gegenbaur  lias  shown  ("  Jenaische  Zeitsclirift,"  Bd.  vii,  ]). 
212)  that  two  distinct  types  of  nipples  prevail  throughout  the  several 
mammalian  orders,  but  that  it  is  quite  intelligible  how  both  could 
have  been  derived  from  the  nipples  of  the  Marsupials,  and  the  latter 
from  those  of  the  Monotremata.  See,  also,  a  memoir  by  Dr.  Max 
Huss,  on  the  mammary  glands,  ibid.,  B.  viii,  p.  176. 

f  Mr.  Lockwood  believes  (as  quoted  in  '  *  Quart.  Journal  of 
Science,"  April,  1868,  p.  269),  from  what  he  has  observed  of  the 
development  of  Hippocampus,  that  the  walls  of  the  abdominal 
pouch  of  the  male  in  some  way  afford  nourishment.  On  male  fishes 
hatching  the  ova  in  their  mouths,  see  a  very  interesting  pa])er  by 
Prof.  Wyman,  in  "  Proc.  Boston  Soc.  of  Nat.  Hist.,"  Sept.  15,  1857; 
also  Prof.  Turner,  in  "Journal  of  Anat.  and  Phys.,"  Nov.  1,  1866,  p. 
78.     Dr.  Giinther  has  likewise  described  similar  cases. 


18G  ^UBi  DESCENT  OF  MAN, 

active.  I'hej  are  sympatlietically  affected  under  the  influ- 
ence of  certain  diseases,  like  the  same  organs  in  the  femalei 
They  often  secrete  a  few  drops  of  milk  at  birth  and  at 
puberty;  this  latter  fact  occurred  in  the  curious  case,  before 
referred  to,  where  a  young  man  possessed  two  pairs  of 
mammae.  In  man  and  some  other  male  mammals  these 
organs  have  been  known  occasionally  to  become  so  well 
developed  during  maturity  as  to  yield  a  fair  supply  of  milk. 
Now  if  we  suppose  that  during  a  former  prolonged  period 
male  mammals  aided  the  females  in  nursing  their  offspring,* 
and  that  afterward  from  some  cause  (as  from  the  production 
of  a  smaller  number  of  young)  the  males  ceased  to  give  this 
aid,  disuse  of  the  organs  during  maturity  would  lead  to  their 
becoming  inactive;  and  from  two  well-known  principles  of 
inheritance,  this  state  of  inactivity  would  probably  be  trans- 
mitted to  the  males  at  the  corresponding  age  of  maturity. 
But  at  an  earlier  age  these  organs  Avould  be  left  unaffected, 
so  that  they  would  be  almost  equally  well  developed  in 
the  young  of  both  sexes. 

Conclusio7i. — Von  Baer  has  defined  advancement  or  prog- 
ress in  the  organic  scale  better  than  any  one  else  as  resting 
on  the  amount  of  differentiation  and  specialization  of  the 
several  parts  of  a  being — when  arrived  at  maturity,  as  I 
should  be  inclined  to  add.  Now,  as  organisms  have  become 
slowly  adapted  to  diversified  lines  of  life  by  means  of  nat- 
ural selection,  their  parts  will  have  become  more  and  more 
differentiated  and  specialized  for  various  functions  from 
the  advantage  gained  by  the  division  of  ^physiological  labor. 
The  same  part  appears  often  to  have  been  modified  first  for 
one  purpose,  and  then  long  afterward  for  some  other  and 
(juite  distinct  purpose;  and  thus  all  the  parts  are  rendered 
more  and  more  complex.  But  each  organism  still  retains 
the  general  type  of  structure  of  the  progenitor  from  which 
it  was  aboriginally  derived.  In  accordance  with  this  view 
it  seems,  if  we  turn  to  geological  evidence,  that  organiza- 
tion on  the  whole  has  advanced  throughout  the  world  by 
slow  and  interrupted  steps.  In  the  great  kingdom  of  the 
vertebrata  it  has  culminated  in  man.  It  must  not,  how- 
ever, be  supposed  that  groups  of  organic  beings  are  always 

*Maddle.  C.  Royer  has  suggested  a  similar  view  iu  her  "  Origine 
de  rilomme,"  etc.,  1870. 


AFFlNlTim  AND  0  ENEALOO  Y.  187 

feupplanted  and  disappear  as  soon  as  they  have  given  bii*th 
to  other  and  more  perfect  groups.  The  latter,  though 
victorious  over  their  predecessors,  may  not  have  become 
better  adapted  for  all  places  in  the  economy  of  nature. 
Some  old  forms  appear  to  have  survived  from  inhabiting 
protected  sites  where  they  have  not  been  exposed  to  very 
severe  competition;  and  these  often  aid  us  in  constructing 
our  genealogies  by  giving  us  a  fair  idea  of  former  and  lost 
populations.  But  we  must  not  fall  into  the  error  of  look- 
ing at  the  existing  members  of  any  lowly  organized  group 
as  perfect  representatives  of  their  ancient  predecessors. 

The  most  ancient  progenitors  in  the  kingdom  of  the 
vertebrata,  at  which  we  are  able  to  obtain  an  obscure  glance, 
apparently  consisted  of  a  group  of  marine  animals*  resem- 
bling the  larvae  of  existing  Ascidians.  These  animals 
probably  gave  rise  to  a  group  of  fishes,  as  lowly  organized 
as  the  lancelet ;  and  from  these  the  Ganoids,  and  other 
fishes  like  the  Lepidosiren,  must  have  been  developed. 
From  such  fish  a  very  small  advance  would  carry  us  on  to 
the  Amphibians.     We  have  seen  that  birds  and   reptiles 

*  The  inhabitants  of  the  seashore  must  be  greatly  affected  by  the 
tides;  animals  living  either  about  the  mean  high- water  mark,  or  about 
the  mean  low-water  mark,  pass  through  a  complete  cycle  of  tidal 
changes  in  a  fortnight.  Consequently  their  food  supply  will  undergo 
marked  changes  week  by  week.  The  vital  functions  of  such  ani- 
mals, living  under  these  conditions  for  many  generations,  can  hardly 
fail  to  run  their  course  in  regular  weekly  periods.  Now  it  is  a  mys- 
terious fact  that  in  the  higher  and  now  terrestrial  vertebrata,  as  well 
as  in  other  classes,  many  normal  and  abnormal  processes  have  one  or 
more  whole  weeks  as  their  periods;  this  would  be  rendered  intelligi- 
ble if  the  vertebrata  are  descended  from  an  animal  allied  to  the 
existing  tidal  Ascidians.  Many  instances  of  such  periodic  processes 
might  be  given,  as  the  gestation  of  mammals,  the  duration  of  fevers, 
etc.  The  hatching  of  eggs  affords  also  a  good  example,  for,  accord- 
ing to  Mr.  Bartlett  ("  Land  and  Water,"  Jan.  7,  1871),  the  eg^s  of 
the  pigeon  are  hatched  in  two  weeks;  those  of  the  fowl  in  three; 
those  of  the  duck  in  four;  those  of  the  goose  in  five;  and  those  of  the 
ostrich  in  seven  weeks.  As  far  as  we  can  judge,  a  recurrent  period, 
if  approximately  of  the  right  duration  for  any  process  of  function, 
would  not,  when  once  gained,  be  liable  to  change;  consequently  it 
might  be  thus  transmitted  through  almost  any  number  of  genera- 
tions. But  if  the  function  changed,  the  period  would  have  to 
change,  and  would  be  apt  to  change  almost  abruptly  by  a  whole 
week.  This  conclusion,  if  sound,  is  highly  remarkable;  for  the 
period  of  gestation  in  each  mammal,  and  the  hatching  of  each  bird's 
eggs,  and  many  other  vital  i)r()cesses,  thus  betray  to  us  the  primor- 
dial birthplace  of  these  aniu'uls. 


188  THE  DRSGENT  OF  MAN. 

were  once  intimately  connected  together;  and  the  Monotre- 
mata  now  connect  mammals  with  reptiles  in  a  slight  degree. 
But  no  one  can  at  present  say  by  what  line  of  descent  the 
three  higher  and  related  classes,  namely,  mammals,  birds, 
and  reptiles,  were  derived  from  the  two  lower  vertebrate 
classes,  namely,  amphibians  and  fishes.  In  the  class  of 
mammals  the  steps  are  not  difficult  to  conceive  which  led 
from  tlie  ancient  Monotremata  to  the  ancient  Marsupials  ; 
and  from  these  to  the  early  progenitors  of  the  placental 
mammals.  We  may  thus  ascend  to  the  Lemuridae;  and  the 
interval  is  not  very  wide  from  these  to  the  Simiadse.  The 
Simiadae  then  branched  oft*  into  two  great  stems,  the  New 
World  and  Old  World  monkeys;  and  from  the  latter  at  a 
remote  period,  Man,  the  wonder  and  glory  of  the  universe, 
proceeded. 

Thus  we  have  given  to  man  a  pedigree  of  prodigious 
length,  but  not,  it  may  be  said,  of  noble  quality.  The 
world,  it  has  often  been  remarked,  appears  as  if  it  had  long 
been  preparing  for  the  advent  of  man;  and  this,  in  one 
sense,  is  strictly  true,  for  he  owes  his  birth  to  a  long  line  of 
progenitors.  If  any  single  link  in  this  chain  had  never 
existed,  man  would  not  have  been  exactly  what  he  now  is. 
Unless  we  wilfully  close  our  eyes,  we  may,  with  our  pres- 
ent knowledge,  approximately  recognize  our  parentage;  nor 
need  we  feel  ashamed  of  it.  The  most  humble  organism  is 
something  much  higher  than  the  inorganic  dust  under  our 
feet ;  and  no  one  with  an  unbiased  mind  can  study  any 
living  creature,  however  humble,  without  being  struck  with 
enthusiasm  at  its  marvelous  structure  and  properties. 


THE  RACES  OF  MAN,  189 


CHAPTER  VII. 

ON   THE    RACES   OF   MAN. 

The  nature  and  value  of  specific  cliaracters — Application  to  tlie 
races  of  man — Arguments  in  favor  of,  and  opposed  to,  ranking 
the  so-called  races  of  man  as  distinct  species — Sub-species — 
Monogenists  and  polygenists  —  Convergence  of  character  — 
Numerous  points  of  resemblance  in  body  and  mind  between  the 
most  distinct  races  of  man — The  state  of  man  when  he  first 
spread  over  the  earth — Each  race  not  descended  from  a  single 
pair — The  extinction  of  races— The  formation  of  races — The 
effects  of  crossing — Slight  influence  of  the  direct  action  of  the 
conditions  of  life — Slight  or  no  influence  of  natural  selection — 
Sexual  selection. 

It  is  not  my  intention  here  to  describe  the  several  so- 
called  races  of  men;  but  I  am  about  to  inquire  what  is  the 
value  of  the  differences  between  them  under  a  classificatory 
point  of  view  and  how  they  have  originated.  In  determin- 
ing whether  two  or  more  allied  forms  ought  to  be  ranked 
as  species  or  varieties,  naturalists  are  practically  guided  by 
the  following  considerations,  namely,  the  amount  of  differ- 
ence between  them,  and  whether  such  differences  relate  to 
few  or  many  points  of  structure,  and  whether  they  are  of 
physiological  importance;  but  more  especially  whether  they 
are  constant.  Constancy  of  character  is  what  is  chiefly 
valued  and  sought  for  by  naturalists.  Whenever  it  can  be 
shown,  or  rendered  probable,  that  the  forms  in  question 
have  remained  distinct  for  •  a  long  period,  this  becomes  an 
argument  of  much  weight  in  favor  of  treating  them  as 
species.  Even  a  slight  degree  of  sterility  between  any  two 
forms  when  first  crossed,  or  in  their  offspring,  is  generally 
considered  as  a  decisive  test  of  their  specific  distinctness; 
and  their  continued  persistence  without  blending  within 
the  same  area,  is  usually  accepted  as  sufficient  evidence, 
either  of  some  degree  of  mutual  sterility,  or  in  the  case  of 
animals  of  some  mutual  repugnance  to  pairing. 

Independently  of  fusion  from  intercrossing,  the  complete 
absence,  in  a  well-investigated  region,  of  varieties  linking 


190  THE  DESCENT  OF  MAN, 

together  any  two  closely  allied  forms,  is  probably  the  most 
important  of  all  the  criterions  of  their  specific  distinctness; 
and  this  is  a  somewhat  different  consideration  from  mere 
constancy  of  character,  for  two  forms  may  be  highly  vari- 
able and  yet  not  yield  intermediate  varieties.  Geographical 
distribution  is  often  brought  into  play  unconsciously  and 
sometimes  consciously;  so  that  forms  living  in  two  widely 
separated  areas,  in  which  most  of  the  other  inhabitants  are 
specifically  distinct,  are  themselves  usually  looked  at  as  dis- 
tinct; but  in  truth  this  affords  no  aid  in  distinguishing 
geographical  races  from  so-called  good  or  true  species. 

Now  let  us  apply  these  generally  admitted  principles  to 
the  races  of  man,  viewing  him  in  the  same  spirit  as  a  nat- 
uralist would  any  other  animal.  In  regard  to  the  amount 
of  difference  between  the  races,  we  must  make  some  allow- 
ance for  our  nice  powers  of  discrimination  gained  by  the 
long  habit  of  observing  ourselves.  In  India,  as  Elphinstone 
remarks,  although  a  newly  arrived  European  cannot  at  first 
distinguish  the  various  native  races,  yet  they  soon  appear 
to  him  extremely  dissimilar;*  and  the  Hindoo  canuot  at 
first  perceive  any  difference  between  the  several  European 
nations.  Even  the  most  distinct  races  of  man  are  much 
more  like  each  other  in  form  than  would  at  first  be  sup- 
posed; certain  negro  tribes  must  be  excepted,  while  others, 
as  Dr.  Rohlf s  writes  to  me,  and  as  I  have  myself  seen,  have 
Caucasian  features.  This  general  similarity  is  well  shown 
by  the  French  photographs  in  the  Collection  Anthropolo- 
gique  du  Museum  de  Paris  of  the  men  belonging  to  various 
races,  the  greater  number  of  which  might  pass  for  Euro- 
peans, as  many  persons  to  whom  I  have  shown  them  have 
remarked.  Nevertheless,  these  men,  if  seen  alive,  would 
undoubtedly  appear  very  distinct,  so  that  we  are  clearly 
much  infiuenced  in  our  judgment  by  the  mere  color  of  the 
skin  and  hair,  by  alight  differences  in  the  features,  and  by 
expression. 

There  is,  however,  j\o,  doubt  that  the  various  races,  when 
carefully  compared  and  Tfleasur^d,  differ  much  from  each 
other — as  in  the  texture  (4  the  hair,  the  relative  propor- 
tions  of  all    parts  of    the  bQdy,f    the    capacity    of   the 

*"  History  of  India,"  1841,  vol,  i,  p.  323.  Fatter  Ripa  makes 
exactly  the  same  remark  with  respect  to  (liinese. 

\  A  vast  number  of  measurements  of  Whites,  Blacks  and  Indians 
are  given  io  the  ' '  Investigations  in  the  Military  and  Anthropolog. 


THE  RACES  OF  MAN.  191 

lungs,  the  form  and  capacity  of  the  skull,  and  even 
ill  the  convolutions  of  the  brain.*  But  it  would  be 
an  endless  task  to  specify  the  numerous  points  of  dif- 
ference. The  races  differ  also  in  constitution,  in  acclima- 
tization and  in  liability  to  certain  diseases.  Their  mental 
characteristics  are  likewise  very  distinct;  chiefly  as  it  would 
appear  in  their  emotional,  but  partly  in  their  intellectual 
faculties.  Every  one  who  has  had  the  opportunity  of  com- 
parison, must  have  been  struck  with  the  contrast  between 
the  taciturn,  even  morose,  aborigines  of  South  America  and 
the  light-hearted,  talkative  negroes.  There  is  a  nearly  sim- 
ilar contrast  between  the  Malays  and  the  Papuans,!  ^^'ho 
live  under  the  same  physical  condition,  and  are  separated 
from  each  other  only  by  a  narrow  space  of  sea. 

We  will  first  consider  the  arguments  which  may  be 
advanced  in  favor  of  classing  the  races  of  man  as  distinct 
species,  and  then  the  arguments  on  the  other  side.  If  a 
naturalist,  who  had  never  before  seen  a  ^'^egro,  Hottentot, 
Australian  or  Mongolian,  were  to  compare  them,  he  would 
at  once  perceive  that  they  differed  in  a  multitude  of  char- 
acters, some  of  slight  and  some  of  considerable  importance. 
On  inquiry  he  would  find  that  they  were  adapted  to  live  under 
widely  different  climates,  and  that  they  differed  somewhat  in 
bodily  constitution  and  mental  disposition.  If  he  were 
then  told  that  hundreds  of  similar  specimens  could  be 
brought  from  the  same  countries,  he  would  assuredly 
declare  that  they  were  as  good  species  as  many  to  which  he 
had  been  in  the  habit  of  affixing  specific  names.  This  con- 
clusion would  be  greatly  strengthened  as  soon  as  he  had 
ascertained  that  these  forms  had  all  retained  the  same 
character  for  many  centuries;  and  that  negroes,  apparently 
identical  with  existing  negroes,  had  lived  at  least  4,000 
years  ago.  J     He  would  also  hear,  on  the  authority  of  an 

Statistics  of  American  Soldiers,"  by  B.  A.  Gould,  1869,  pp.  298-358; 
"  On  the  capacity  of  the  lungs,"  p.  471.  See  also  the  numerous  and 
valuable  tables,  by  Dr.  Weisbach,  from  the  observations  of  Dr. 
Scherzerand  Dr.  Schwarz,  in  the  *' Reise  der  Novara;  Anthropolog. 
Theil,"  1867. 

*  See,  for  instance,  Mr.  Marshall's  account  of  the  brain  of  a  Bush- 
woman,  in  "Phil.  Transact.,"  1864,  p.  519. 

fWailace,  "  The  Malay  Archipelago,"  voL  ii,  1869,  p.  178. 

X  With  respect  to  the  figures  in  the  famous  Egyptian  caves  of 
Abou-Simbel,   M,    Pouchet  says    ("The    Pluralitv   of  the   Human 


192  THE  DESCENT  OF  MAN. 

excellent  observer.  Dr.  Lund,*  that  the  human  skulls 
found  in  the  caves  of  Brazil,  entombed  with  many  extinct 
mammals,  belonged  to  the  same  type  as  that  now  prevail- 
ing throughout  the  American  Continent. 

Our  naturalist  would  then  perhaps  turn  to  geograjihical 
distribution,  and  he  would  probably  declare  that  those 
forms  must  be  distinct  species,  which  differ  not  only  in 
appearance,  but  are  fitted  for  hot,  as  well  as  damp  or  dry 
countries,  and  for  the  Arctic  regions.  He  might  appeal  to 
the  fact  that  no  species  in  the  group  next  to  man — namely, 
the  Quadrumana,  can  resist  a  low  temperature,  or  any  con- 
siderable change  of  climate;  and  that  the  species  which 
come  nearest  to  man  have  never  been  reared  to  maturity, 
even  under  the  temperate  climate  of  Europe.  He  would 
be  deeply  impressed  with  the  fact,  first  noticed  by  Agassiz,f 
that  the  different  races  of  man  are  distributed  over  the 
world  in  the  same  zoological  provinces,  as  those  inhabited 
by  undoubtedly  distinct  species  and  genera  of  mammals. 
This  is  manifestly  the  case  with  the  Australian,  Mongolian, 
and  Negro  races  of  man;  in  a  less  well-marked  manner 
with  the  Hottentots;  but  plainly  wdth  the  Papuans  and 
Malays,  who  are  separated,  as  Mr.  Wallace  has  shown,  by 
nearly  the  same  line  which  divides  the  great  Malayan  and 
Australian  zoological  provinces.  The  Aborigines  of  America 

Races,"  Eng.  translat.,  1864,  p.  50),  that  lie  was  far  from  finding 
recognizable  representations  of  the  dozen  or  more  nations  which 
some  authors  believe  that  they  can  recognize.  Even  some  of  the 
most  strongly-marked  races  cannot  be  identified  with  that  degree  of 
unanimity  which  might  have  been  expected  from  what  has  been 
written  on  the  subject.  Thus  Messrs.  Nott  and  Gliddon  ("  Types  of 
Mankind,"  p.  148),  state  that  Rameses  II,  or  the  Great,  has  features 
superbly  European;  whereas  Knox,  another  firm  believer  in  the 
specific  distinctness  of  the  races  of  man  ("  Races  of  Man,"  1850,  p. 
201),  speaking  of  young  Memnon  (the  same  as  Rameses  II,  as  1  am 
informed  by  Mr.  Birch),  insists  in  the  strongest  manner  that  he  is 
identical  in  character  with  the  Jews  of  Antwerp.  Again,  when  I 
looked  at  the  statue  of  Amunoph  III,  I  agreed  with  two  officers  of 
the  establishment,  both  competent  judges,  that  he  had  a  strongly- 
marked  negro  type  of  features;  but  Messrs.  Nott  and  Gliddon  (ibid, 
p.  146,  fig.  53),  describe  him  as  a  hybrid,  but  not  of  "negro  inter- 
mixture." 

*  As  quoted  by  Nott  and  Gliddon,  "  Types  of  Mankind,"  1854,  p.  439. 
They  give  also  corroborative  evidence;  but  C.  Vogt  thinks  that  the 
subject  requires  further  investigation. 

f  "  Diversity  of  Origin  of  the  Human  Races,"  in  the  "Christian 
Examiner,"  July,  1850. 


THR  RACES  OF  MAN.  193 

range  throughout  the  Continent;  and  this  at  first  appears 
opposed  to  the  above  rule,  for  most  of  the  productions  of 
the  Southern  and  Northern  halves  differ  widely;  yet  some 
few  living  forms,  as  the  ojjossum,  range  from  the  one  into 
the  other,  as  did  formerly  some  of  the  gigantic  Edentata. 
The  Esquimaux,  like  other  xerotic  animals,  extend  round  the 
whole  polar  regions.  It  should  .be  observed  that  the 
amount  of  difference  between  the  mammals  of  the  several 
zoological  provinces  does  not  correspond  with  the  degree  of 
separation  between  the  latter;  so  that  it  can  hardly  be  con- 
sidered as  an  anomaly  that  the  Xegro  differs  more,  and  the 
American  much  less  from  the  other  races  of  man,  than  do 
the  mammals  of  the  African  and  American  Continents 
from  the  mammals  of  the  other  provinces.  Man,  it  may  be 
added,  does  not  appear  to  have  aboriginally  inhabited  any 
oceanic  island;  and  in  this  respect  he  resembles  the  other 
members  of  his  class. 

In  determining  whether  the  supposed  varieties  of  the 
same  kind  of  domestic  animal  should  be  ranked  as  such,  or 
as  specifically  distinct,  that  is,  whether  any  of  them  are 
descended  from  distinct  wild  species,  every  naturalist  would 
lay  much  stress  on  the  fact  of  their  external  parasites  being 
specifically  distinct.  All  the  more  stress  would  be  laid  on 
this  fact,  as  it  would  be  an  exceptional  one;  for  I  am  in- 
formed by  Mr.  Denny  that  the  most  different  kinds  of 
dogs,  fowls  and  pigeons  in  England  are  infested  by  the 
same  species  of  Pediculi  or  lice.  Now  Mr.  A.  Murray  has 
carefully  examined  the  Pediculi  collected  in  different  coun- 
tries from  the  different  races  of  man;*  and  he  finds  that 
they  differ,  not  only  in  color,  but  in  the  structure  of  their 
claws  and  limbs.  In  every  case  in  which  many  specimens 
were  obtained  the  differences  were  constant.  The  surgeon 
of  a  whaling  ship  in  the  Pacific  assured  me  that  when  the 
Pediculi,  with  which  some  Sandwich  Islanders  on  board 
swarmed,  strayed  on  to  the  bodies  of  the  English  sailoi*s 
they  died  in  the  course  of  three  or  four  days.  These  Pedi- 
culi were  darker  colored  and  appeared  different  from  those 
proper  to  the  natives  of  Chili,  in  South  America,  of  which 
he  gave  me  specimens.  These,  again,  appeared  larger  and 
much  softer  than  European  lice.  Mr.  Murray  procured 
four  kinds  from  Africa,  namely,  from  the  Negroes  of  the 

*  "Transact.  R.  Soc.  of  Edinburgh,"  vol.  xxii,  1861,  p.  567. 


194  THE  DESCENT  OF  MAN. 

Eastern  and  Western  coasts,  from  the  Hottentots  and 
Kaffirs;  two  kinds  from  tlie  natives  of  Australia;  two  from 
North  and  two  from  South  America.  In  these  latter  cases 
it  may  be  presumed  that  the  Pediculi  came  from  natives 
iniiabiting  different  districts.  With  insects  slight  struct- 
ural differences,  if  constant,  are  generally  esteemed  of 
specific  value;  and  the  fact  of  the  races  of  man  being  in- 
fested by  parasites  which  appear  to  be  specifically  distinct 
might  fairly  be  urged  as  an  argument  that  the  races  them- 
selves ought  to  be  classed  as  distinct  species. 

Our  supposed  naturalist  having  proceeded  thus  far  in  his 
investigation  would  next  inquire  whether  the  races  of  men, 
when  crossed,  were  in  any  degree  sterile.  He  might  con- 
sult the  work*  of  Prof.  Broca,  a  cautious  and  philosophical 
observer,  and  in  this  he  would  find  good  evidence  that 
some  races  were  quite  fertile  together,  but  evidence  of  an 
opposite  nature  in  regard  to  other  races.  Thus  it  has  been 
asserted  that  the  native  women  of  Australia  and  Tasmania 
rarely  produce  children  to  European  men;  the  evidence, 
however,  on  this  head  has  now  been  shown  to  be  almost 
valueless.  The  half-castes  are  killed  by  the  pure  blacks; 
and  an  account  has  lately  been  published  of  eleven  half- 
caste  youths  murdered  and  burned  at  the  same  time  whose 
remains  were  found  by  the  police  f  Again,  it  has  often 
been  said  that  when  mulattoes  intermarry  they  produce 
few  children;  on  the  other  hand,  Dr.  Bachman,  of  Charles- 
ton, J  positively  asserts  that  he  has  known  mulatto  families 
which  have  intermarried  for  several  generations,  and  have 
continued  on  an  average  as  fertile  as  either  pure  whites  or 
pure  blacks.  Inquiries  formerly  made  by  Sir  C.  Lyell  on 
this  subject  led  him,  as  he  informs  me,  to  the  same  con- 

*"0n  the  Phenomena  of  Hybridity  in  the  Genus  Homo,"  Eng. 
translat.,  1864. 

f  See  the  interesting  letter  by  Mr.  T.  A.  Murray,  in  the  "  Anthro- 
polog.  Review,"  April,  1868,  p.  53.  In  this  letter  Count  Strzelecki's 
statement  that  Australian  women  who  have  borne  children  to  a  white 
man,  are  afterward  sterile  with  their  own  race,  is  disproved.  M.  A. 
de  Quatrefages  has  also  collected  ("  Revue  des  Cours  Scientifiques," 
March,  1869,  p.  239)  much  evidence  that  Australians  and  Europeans 
are  not  sterile  when  crossed. 

X  "  An  Examination  of  Prof.  Agassiz's  Sketch  of  the  Nat.  Province^ 
of  the  Aniuial  World/'  Charleston,  1855,  p.  44, 


THE  RACES  OF  MAN.  195 

elusion.*  Ill  the  Uiiited  States  the  eensus  for  the  year 
1854  inckided,  according  to  Dr.  Bachman,  405,751  mulat- 
toes;  and  this  number,  considering  all  the  circumstances 
of  the  case,  seems  small;  but  it  may  partly  be  accounted  for 
by  the  degraded  and  anomalous  position  of  the  class  and 
by  the  profligacy  of  the  women.  A  certain  amount  of 
absorption  of  mulattoes  into  negroes  must  always  be  in 
progress;  and  this  woukl  lead  to  an  apparent  diminution  of 
the  former.  The  inferior  vitality  of  mulattoes  is  spoken  of 
in  a  trustworthy  workf  as  a  well-known  phenomenon;  and 
this,  although  a  different  consideration  from  their  lessened 
fertility,  may  perhaps  be  advanced  as  a  proof  of  the  specific 
distinctness  of  the  parent  races.  No  doubt  both  animal 
and  vegetable  hybrids,  when  produced  from  extremely  dis- 
tinct species,  are  liable  to  premature  death;  but  the  parents 
of  mulattoes  cannot  be  put  under  the  catagory  of  extremely 
distinct  species.  The  common  mule,  so  notorious  for  long 
life  and  vigor,  and  yet  so  sterile,  shows  how  little  necessary 
connection  there  is  in  hybrids  between  lessened  fertility 
and  vitality;  other  analogous  cases  could  be  cited. 

Even  if  it  should  hereafter  be  proved  that  all  the  races 
of  men  were  perfectly  fertile  together,  he  who  was  inclined 
from  other  reasons  to  rank  them  as  distinct  species,  might 
with  justice  argue  that  fertility  and  sterility  are  not  safe 
criterions  of  specific  distinctness.  We  know  that  these 
qualities  are  easily  affected  by  changed  conditions  of  life, 
or  by  close  inter-breeding,  and  that  they  are  governed  by 
highly  complex  laws,  for  instance,  that  of  the  unequal  fer- 
tility of  converse  crosses  between  the  same  two  species. 
With  forms  which  must  be  ranked  as  undoubted  species,  a 
perfect  series  exists  from  those  which  are  absolutely  sterile 
when  crossed,  to  those  which  are  almost  or  completely  fer- 
tile.    The  degrees  of  sterility  do  not  coincide  strictly  with 

*  Dr.  Rohlfs  writes  to  me  that  he  found  the  mixed  races  in  the 
Great  Sahara,  derived  from  Arabs,  Berbers,  and  Negroes  of  three 
tribes,  extraordinarily  fertile.  On  the  other  hand,  Mr.  Winwood 
Reade  informs  me  that  the  Negroes  on  the  Gold  Coast,  though  admir- 
ing white  men  and  mulattoes,  have  a  maxim  that  mulattoes  should 
not  intermarry,  as  the  children  are  few  and  sickly.  This  belief,  as 
Mr.  Reade  remarks,  deserves  attention,  as  white  men  have  visited 
and  resided  on  the  Gold  Coast  for  four  hundred  years,  so  that  the 
natives  have  had  ample  time  to  gain  knowledge  through  experience. 

f  "  Military  and  Anthropolog.  Statistics  of  American  Soldiers,"  by 
B.  A.  Gould,  1869,  p.  319. 


196  THE  DESCENT  OF  MAN. 

the  degrees  of  difference  between  the  parents  in  external 
structure  or  habits  of  life.  Man  in  many  respects  may  be 
compared  with  those  animals  which  have  long  been  domes- 
ticated, and  a  large  body  of  evidence  can  be  advanced  in 
favor  of  the  Pallasian  doctrine,*  that  domestication  tends 
to  eliminate  the  sterility  which  is  so  general  a  result  of  the 
crossing  of  species  in  a  state  of  nature.  From  these  sev- 
eral considerations,  it  may  be  justly  urged  that  the  perfect 
fertility  of  the  intercrossed  races  of  man,  if  established, 
would  not  absolutely  preclude  us  from  ranking  them  as 
distinct  species. 

Independently  of  fertility,  the  characters  presented  by 
the  offspring  from  a  cross  have  been  thought  to  indicate 
whether  or  not  the  parent-forms  ought  to  be  ranked  as 

*  '*  The  Variation  of  Animals  and  Plants  under  Domestication,"  vol. 
ii,  p.  109.  I  may  here  remind  the  reader  that  the  sterility  of  species 
when  crossed  is  not  a  specially  acquired  quality,  but,  like  the  inca- 
pacity of  certain  trees  to  be  grafted  together,  is  incidental  on  other 
acquired  differences.  The  nature  of  these  differences  is  unknown, 
but  they  relate  more  especially  to  the  reproductive  system,  and  much 
less  so  to  external  structure  or  to  ordinary  differences  in  constitution. 
One  important  element  in  the  sterility  of  crossed  species  apparently 
lies  in  one  or  both  having  been  long  habituated  to  fixed  conditions; 
for  we  know  that  changed  conditions  have  a  special  influence  on  the 
reproductive  system,  and  we  have  good  reason  to  believe  (as  before 
remarked)  that  the  fluctuating  conditions  of  domestication  tend  to 
eliminate  that  sterility  which  is  so  general  with  species,  in  a  natural 
state,  when  crossed.  It  has  elsewhere  been  shown  by  me  (ibid.,  vol. 
ii,  p.  185,  and  "  Origin  of  Species,"  5th  edit.,  p.  317),  that  the  steril- 
ity of  crossed  species  has  not  been  acquired  through  natural  selection; 
we  can  see  that  when  two  forms  have  already  been  rendered  very 
sterile,  it  is  scarcely  possible  that  their  sterility  should  be  aug- 
mented by  the  preservation  or  survival  of  the  more  and  more  sterile 
individuals;  for,  as  the  sterility  increases,  fewer  and  fewer  offspring 
will  be  produced  from  which  to  breed,  and  at  last  only  single  indi- 
viduals will  be  produced  at  the  rarest  intervals.  But  there  is  even  a 
higher  grade  of  sterility  than  this.  Both  Gartner  and  Kol renter 
have  proved  that  in  genera  of  plants,  including  many  species,  a  series 
can  be  formed  from  species  which,  when  crossed,  yield  fewer  and 
fewer  seeds,  to  species  which  never  produce  a  single  seed,  but  yet 
are  affected  by  the  pollen  of  the  other  species,  as  shown  by  the 
swelling  of  the  germen.  It  is  here  manifestly  impossible  to  select 
the  more  sterile  individuals,  which  have  already  ceased  to  yield' 
seeds;  so  that  the  acme  of  sterility,  when  the  germen  alone  is 
affected,  cannot  have  been  gained  through  selection.  This  acme, 
and  no  doubt  the  other  grades  of  sterility,  are  the  incidental  results 
of  certain  unknown  differences  in  the  constitution  of  the  reproductive 
system  of  the  species  which  are  crossed. 


THE  UACm  OP*  MAIT.  197 

species  or  varieties;  but  after  carefully  studying  the  evi- 
dence, I  have  come  to  the  conclusion  that  no  general  rules 
of  this  kind  can  be  trusted.  The  ordinary  result  of  a  cross 
is  the  production  of  a  blended  or  intermediate  form;  but  in 
certain  cases  some  of  the  offspring  take  closely  after  one 
parent-form  and  some  after  the  other.  This  is  especially 
apt  to  occur  when  the  parents  differ  in  characters  which 
first  appeared  as  sudden  variations  or  monstrosities.*  I 
refer  to  this  point  because  Dr.  Rohlfs  informs  me  that  he 
has  frequently  seen  in  Africa  the  offspring  of  negroes  crossed 
with  members  of  other  races,  either  completely  black  or 
completely  white,  or  rarely  piebald.  On  the  other  hand,  it 
is  notorious  that  in  America  mulattoes  commonly  present 
an  intermediate  appearance. 

We  have  now  seen  that  a  naturalist  might  feel  himself 
fully  justified  in  ranking  the  races  of  man  as  distinct  spe- 
cies; for  he  has  found  that  they  are  distinguished  by  many 
difli'erences  in  structure  and  constitution,  some  being  of 
importance.  These  differences  have  also  remained  nearly 
constant  for  very  long  periods  of  time.  Our  naturalist  will 
have  been  in  some  degree  influenced  by  the  enormous  range 
of  man,  which  is  a  great  anomaly  in  the  class  of  mammals, 
if  mankind  be  viewed  as  a  single  species.  He  will  have 
])een  struck  with  the  distribution  of  the  several  so-called 
races,  which  accords  with  that  of  other  undoubtedly  dis- 
tinct species  of  mammals.  Finally,  he  might  urge  that  the 
mutual  fertility  of  all  the  races  has  not  as  yet  been  fully 
proved,  and  even  if  proved  would  not  be  an  absolute  proof 
of  their  specific  identity. 

On  the  other  side  of  the  question,  if  our  supposed  nat- 
uralist were  to  inquire  whether  the  forms  of  man  keep  dis- 
tinct like  ordinary  species  when  mingled  together  in  large 
numbers  in  the  same  country,  he  would  immediately  dis- 
cover that  this  was  by  no  means  the  case.  In  Brazil  he 
would  behold  an  immense  mongrel  population  of  Negroes 
and  Portuguese;  in  Chili  and  other  parts  of  South  Amer- 
ica he  would  behold  the  whole  population  consisting  of  In- 
dians aud  Spaniards  blended  in  various  degrees,  f    In  many 

*  "  The  Variation  of  Animals,"  etc.,  vol.  ii,  p.  92. 

f- M.  de  Quatrefages  has  given  ("  Anthropolog.  Review,"  Jan., 
18(59.  p.  22)  an  interesting  account  of  the  success  and  energy  of  the 
i*aulistas  in  Brazil,  who  are  a  much  crossed  race  of  Portuguese  and 
Indians,  with  a  mixture  of  the  blood  of  other  races. 


10,^  TBE  DESCENT  OP  MAIT. 

parts  of  the  same  continent  he  would  meet  with  the  most 
complex  crosses  between  Negroes,  Indians,  and  Europeans; 
and  Judging  from  the  vegetable  kingdom  such  triple 
crosses  afford  the  severest  test  of  the  mutual  fertility  of  the 
parent  forms.  In  one  island  of  the  Pacific  he  would  find  a 
small  population  of  mingled  Polynesian  and  English  blood; 
and  in  the  Fiji  Archipelago  a  population  of  Polynesian  and 
Negritos  crossed  in  all  degi-ees.  Many  analogous  cases 
could  be  added;  for  instance,  in  Africa.  Hence  the  races 
of  man  are  not  sufficiently  distinct  to  inhabit  the  same 
country  without  fusion;  and  the  absence  of  fusion  affords 
the  usual  and  best  test  of  specific  distinctness. 

Our  naturalist  would  likewise  be  much  disturbed  as  soon 
as  he  perceived  that  the  distinctive  characters  of  all  the 
races  were  highly  variable.  This  fact  strikes  every  one  on 
first  beholding  the  negro  slaves  in  Brazil,  who  have  been 
imported  from  all  parts  of  Africa.  The  same  remark  holds 
good  with  the  Polynesians,  and  with  many  other  races.  It 
may  be  doubted  whether  any  character  can  be  named 
which  is  distinctive  of  a  race  and  is  constant.  Savages, 
even  within  the  limits  of  the  same  tribe,  are  not  nearly  so 
uniform  in  character,  as  has  been  often  asserted.  Hotten- 
tot women  offer  certain  peculiarities,  more  strongly  marked 
than  those  occurring  in  any  other  race,  but  these  are 
known  not  to  be  of  constant  occurrence.  In  the  several 
American  tribes,  color  and  hairiness  differ  considerably;  as 
does  color  to  a  certain  degree,  and  the  shape  of  the 
features  greatly,  in  the  negroes  of  Africa.  The  shape  of 
the  skull  varies  much  in  some  races;*  and  so  it  is  with 
every  other  character.  Now  all  naturalists  have  learned  by 
dearly  bought  experience  how  rash  it  is  to  attempt  to  define 
species  by  the  aid  of  inconstant  characters. 

But  the  most  weighty  of  all  the  arguments  against  treat- 
ing the  races  of  man  as  distinct  species,  is  that  they  gradu- 
ate into  each  other,  independently  in  many  cases,  as  far  as 
we  can  judge,  of  their  having  intercrossed.  Man  has  been 
studied  more  carefully  than  any  other  animal,  and  yet  there 
is  the  greatest  possible  diversity  among  capable  judges 
whether  he  should  be  classed  as  a  single  species  or  race,  or 

*  For  instance,  with  the  aborigines  of  America  and  Australia.  Prof. 
Huxley  says  ("  Transact.  Internat.  Congress  of  Preliist  Arch."  1868, 
]).  105)  that  the  skulls  of  many  South  Germans  and  Swiss  are  "  as 
short  and  as  broad  as  those  of  the  Tartars,"  etc. 


THM  RACES  OF  MAN.  100 

iis  two  (Virey),  as  three  (Jacquinot),  as  four  (Kant),  five 
(Blumenbach),  six  (Buffon),  seven  (Hunter),  eight  (Agas= 
siz),  eleven  (Pickering),  fifteen  (Bory  St.  Vincent),  sixteen 
(Desmoulins),  twenty-two  (Morton),  sixty  (Crawfurd),  of 
as  sixty-three,  according  to  Burke.*  This  diversity  of 
judgment  does  not  prove  that  the  races  ought  not  to  be 
ranked  as  species,  but  it  shows  that  they  graduate  into  each 
other,  and  that  it  is  hardly  possible  to  discover  clear 
distinctive  characters  between  them. 

Every  naturalist  who  has  had  the  misfortune  to  under- 
take the  description  of  a  group  of  highly  varying  organ- 
isms, has  encountered  cases  (I  speak  after  experience) 
precisely  like  that  of  man;  and  if  of  a  cautious  disposition, 
he  will  end  by  uniting  all  the  forms  which  graduate  into 
each  other,  under  a  single  species;  for  he  will  say  to  him- 
self that  he  has  no  right  to  give  names  to  objects  which  he 
cannot  define.  Cases  of  this  kind  occur  in  the  order  which 
includes  man,  namely  in  certain  genera  of  monkeys;  while 
in  other  genera,  as  in  Cercopithecus,  most  of  the  species 
can  be  determined  with  certainty.  In  the  American  genus 
Cebus,  the  various  forms  are  ranked  by  some  naturalists  as 
species,  by  others  as  mere  geographical  races.  Xow  if 
numerous  specimens  of  Cebus  Avere  collected  from  all  parts 
of  South  America,  and  those  forms  which  at  present  appeal- 
to  be  specifically  distinct,  were  found  to  graduate  into  each 
other  by  close  steps,  they  would  usually  be  ranked  as  mere 
varieties  or  races;  and  this  course  has  been  followed  by 
most  naturalists  with  respect  to  the  races  of  man.  Never- 
theless, it  must  be  confessed  that  there  are  forms,  at  least 
in  the  vegetable  kingdom,!  which  we  cannot  avoid  naming 
as  species,  but  which  are  connected  together  by  numberless 
gradations,  independently  of  intercrossing. 

Some  naturalists  have  lately  employed  the  term  "  sub- 
species "  to  designate  forms  which  possess  many  of  the  char- 
acteristics of  true  species,  but  which  hardly  deserve  so  high 

*See  a  good  discussion  on  this  subject  in  Waitz,  "  Introduct,  to 
Anthropology,"  Eng.  translat..  1863,  pp.  198-208,  227.  I  have  taken 
some  of  the  above  statements  from  H.  Tuttle's  * '  Origin  and  Antiquity 
of  Physical  Man,"  Boston,  1866,  p.  35. 

f  Prof.  Nageli  has  carefully  described  several  striking  cases  in  his 
"Botanische  Mittheilumgen,"  B.  ii,  1866,  ss.  294-369.  Prof.  Asa 
Gray  has  made  analogous  remarks  on  some  intermediate  forms  in  the 
Compositae  of  North  America. 


^00  THE  DESCENT  OF  MAN, 

a  rank.  Now  if  we  reflect  on  the  weighty  arguments  above 
given,  for  raising  the  races  of  man  to  the  dignity  of  species, 
and  the  insuperable  difficulties  on  the  other  side  in  defining 
them,  it  seems  that  the  term  ^^  sub-species"  might  here  be 
used  with  propriety.  But  from  long  habit  the  term  '^  race  " 
will  perhaps  always  be  employed.  The  choice  of  terms  is 
only  so  far  important  in  that  it  is  desirable  to  use,  as  far  as 
possible,  the  same  terms  for  the  same  degrees  of  difference. 
Unfortunately  this  can  rarely  be  done;  for  the  larger  genera 
generally  include  closely-allied  forms,  which  can  be  distin- 
guished only  with  much  difficulty,  while  the  smaller  genera 
within  the  same  family  include  forms  that  are  perfectly  dis- 
tinct; yet  all  must  be  ranked  equally  as  species.  So  again, 
species  within  the  same  large  genus  by  no  means  resemble 
each  other  to  the  same  degree;  on  the  contrary,  some  of 
them  can  generally  be  arranged  in  little  groups  round  other 
species,  like  satellites  round  planets.* 

The  question  whether  mankind  consists  of  one  or  sev- 
eral species  has  of  late  years  been  much  discussed  by  anthro- 
pologists, who  are  divided  into  the  two  schools  of  monogen- 
ists  and  polygenists.  Those  who  do  not  admit  the  prin- 
ciple of  evolution  must  look  at  species  as  separate  creations, 
or  as  in  some  manner  as  distinct  entities;  and  they  must 
decide  what  forms  of  man  they  will  consider  as  species  by  the 
analogy  of  the  method  commonly  pursued  in  ranking  other 
organic  beings  as  species.  But  it  is  a  hopeless  endeavor  to 
decide  this  point,  until  some  definition  of  the  term 
*' species  "is  generally  accepted;  and  the  definition  must 
not  include  an  intermediate  element  such  as  an  act  of 
creation.  We  might  as  well  attempt  without  any  definition 
to  decide  whether  a  certain  number  of  houses  should  be 
called  a  village,  town  or  city.  We  have  a  practical  illus- 
tration of  the  difficulty  in  the  never-ending  doubts  whether 
many  closely-allied  mammals,  birds,  insects  and  plants,  which 
represent  each  other  respectively  in  North  America  and 
Europe,  should  be  ranked  as  species  or  geographical  races; 
and  the  like  holds  true  of  the  productions  of  many  islands 
situated  at  some  little  distance  from  the  nearest  continent. 

Those  naturalists,  on  the  other  hand,  who  admit  the 
principle   of   evolution,  and  this  is  now  admitted  by  the 

***  Origin  of  Species,"  5th  edit.  p.  68. 


THE  RACES  OF  MAN.  201 

majority  of  rising  men,  will  feel  no  doubt  that  all  the  races 
of  man  are  descended  from  a  single  primitive  stock  ; 
whether  or  not  they  may  think  fit  to  designate  the  races  as 
distinct  species,  for  the  sake  of  expressing  their  amount  of 
difference.*  With  our  domestic  animals  the  question 
whether  the  various  races  have  arisen  from  one  or  more 
species  is  somewhat  different.  Although  it  may  be  admit- 
ted that  all  the  races,  as  well  as  all  the  natural  species 
within  the  same  genus,  have  sprung  from  the  same  primi- 
tive stock,  yet  it  is  a  fit  subject  for  discussion,  whether  all 
the  domestic  races  of  the  dog,  for  instance,  have  acquired 
their  present  amount  of  difference  since  some  one  species 
was  first  domesticated  by  man;  or  whether  they  owe  some 
of  their  characters  to  inheritance  from  distinct  species, 
which  had  already  been  differentiated  in  a  state  of  nature. 
With  man  no  such  question  can  arise,  for  he  cannot  be  said 
to  have  been  domesticated  at  any  particular  period. 

During  an  early  stage  in  the  divergence  of  the  races  of 
man  from  a  common  stock,  the  differences  between  the 
races  and  their  number  must  have  been  small;  consequently 
as  far  as  their  distinguishing  characters  are  concerned,  they 
then  had  less  claim  to  rank  as  distinct  species  than  the 
existing  so-called  races.  Nevertheless,  so  arbitrary  is  the 
term  of  species,  that  such  early  races  would  perhaps  have 
been  ranked  by  some  naturalists  as  distinct  species,  if  their 
differences,  although  extremely  slight,  had  been  more  con- 
stant than  they  are  at  present,  and  had  not  graduated  into 
each  other. 

It  is,  however,  possible,  though  far  from  probable,  that 
the  early  progenitors  of  man  might  formerly  have  diverged 
much  in  character,  until  they  became  more  unlike  each 
other  than  any  now  existing  races;  but  that  subsequently, 
as  suggested  by  Vogt,  \  they  converged  in  character.  When 
man  selects  the  offspring  of  two  distinct  species  for  the 
same  object,  he  sometimes  induces  a  considerable  amount 
of  convergence,  as  far  as  general  appearance  is  concerned. 
This  is  the  case,  as  shown  by  Von  Nathusius,!  with  the 

*See  Prof.  Huxley  to  this  effect  in  the  "  Fortnightly  Review," 
1865,  p.  275. 

f  "  Lectures  on  Man,"  Eng.  translat.,  1864,  p.  468. 

^"Die  Racen  des  Schweines,"  1860,  s.  46.  "  Vorstudien  far 
(Jeschichte.  etc.,  Schweineschadel,"  1864,  s.  104.  With  respect  to 
cattle,  see  M.  de  Quatrefages,  "Unite  de  I'Espece  Humaine,"  1861, 
p.  119. 


202  THE  DESCENT  OF  MAN, 

improved  breeds  of  the  pig,  which  are  descended  from  two 
distinct  species;  and  in  a  less  marked  manner  with  the 
improved  breeds  of  cattle.  A  great  anatomist,  Gratiolet, 
maintains  that  the  anthropomorphous  apes  do  not  form  a 
natural  sub-group ;  but  that  the  orang  is  a  highly  devel- 
oped gibbon  or  semnopithecus,  the  chimpanzee  a  highly 
developed  macacus,  and  the  gorilla  a  highly  developed  man- 
drill. If  this  conclusion,  which  rests  almost  exclusively  on 
brain-characters,  be  admitted,  we  should  have  a  case  of  con- 
vergence at  least  in  external  characters,  for  the  anthropomor- 
phous apes  are  certainly  more  like  each  other  in  many  points 
than  they  are  to  other  apes.  All  analogical  resemblances,  as  of 
a  whale  to  a  fish,  may  indeed  be  said  to  be  cases  of  con- 
vergence; but  this  term  has  never  been  applied  to  super- 
ficial and  adaptive  resemblances.  It  would,  however,  be 
extremely  rash  to  attribute  to  convergence  close  similarity 
of  character  in  many  points  of  structure  among  the  modi- 
fied descendants  of  widely  distinct  beings.  The  form  of  a 
crystal  is  determined  solely  by  the  molecular  forces,  and  it 
is  not  surprising  that  dissimilar  substances  should  some- 
times assume  the  same  form;  but  with  organic  beings  we 
should  bear  in  mind  that  the  form  of  each  depends  on  an 
infinity  of  complex  relations,  namely,  on  variations  due  to 
causes  far  too  intricate  to  be  followed — on  the  nature  of 
the  variations  preserved,  these  depending  on  the  physical 
conditions,  and  still  more  on  the  surrounding  organisms 
which  compete  with  each — and  lastly,  on  inheritance  (in 
itself  a  fluctuating  element)  from  innumerable  progenitors, 
all  of  which  have  have  had  their  forms  determined  through 
equally  complex  relations.  It  appears  incredible  that  the 
modified  descendants  of  two  organisms,  if  these  differed 
from  each  other  in  a  marked  manner,  should  ever  after- 
ward converge  so  closely  as  to  lead  to  a  near  approach  to 
identity  throughout  their  whole  organization.  In  the  case 
of  the  convergent  races  of  pigs  above  referred  to,  evidence 
of  their  descent  from  two  primitive  stocks  is,  according  to 
Von  Nathusius,  still  plainly  retained  in  certain  bones  of 
their  skulls.  If  the  races  of  man  had  descended,  as  is  sup- 
posed by  some  naturalists,  from  two  or  more  species  which 
differed  from  each  other  as  much,  or  nearly  as  much,  as 
does  the  orang  from  the  gorilla  it  can  hardly  be  doubted 
that  marked  diiferences  in  the  structure  of  certain  bones 
would  still  be  discoverable  in  man  as  he  now  exists. 


THE  RACES  OF  MAN,  203 

Although  the  existing  races  of  man  differ  in  many  re- 
spects as  in  color,  hair,  shape  of  skull,  proportions  of  the 
body,  etc.,  yet  if  their  whole  structure  be  taken  into  con- 
sideration they  are  found  to  resemble  each  other  closely  in 
a  multitude  of  points.  Many  of  these  are  of  so  unimpor- 
tant or  of  so  singular  a  nature  that  it  is  extremely  improb- 
able that  they  should  have  been  independently  acquired  by 
aboriginally  distinct  species  or  races.  The  same  remark 
holds  good  with  equal  or  greater  force  with  respect  to  the 
numerous  points  of  mental  similarity  between  the  most 
distinct  races  of  man.  The  American  aborigines,  Negroes 
and  Europeans  are  as  different  from  each  other  in  mind  as 
any  three  races  that  can  be  named;  yet  I  was  incessantly 
struck  while  living  with  the  Fuegians  on  board  the 
"  Beagle ''  with  the  many  little  traits  of  character  showing 
how  similar  their  minds  were  to  ours;  and  so  it  was  with 
a  full-blooded  negro  with  whom  I  happened  once  to  be 
intimate. 

He  who  will  read  Mr.  Tylor's  and  Sir  J.  Lubbock^s  in- 
teresting works*  can  hardly  fail  to  be  deeply  impressed 
with  the  close  similarity  between  the  men  of  all  races  in 
tastes,  dispositions  and  habits.  This  is  shown  by  the  pleas- 
ure which  they  all  take  in  dancing,  rude  music,  painting, 
tattooing  and  otherwise  decorating  themselves ;  in  their 
mutual  comprehension  of  gesture-language,  by  the  same 
expression  in  their  features,  and  by  the  same  inarticulate 
cries,  when  excited  by  the  same  emotions.  This  similarity, 
or  rather  identity,  is  striking,  when  contrasted  with  the 
different  expressions  and  cries  made  by  distinct  species  of 
monkeys.  There  is  good  evidence  that  the  art  of  shooting 
with  bows  and  arrows  had  not  been  handed  down  from  any 
common  progenitor  of  mankind,  yet  as  Westropp  and 
Nilsson  have  remarked,!  the  stone  arrow-heads,  brought 
from  the  most  distant  parts  of  the  world,  and  manufactured 
at  the  most  remote  periods,  are  almost  identical;  and  this 
fact  can  only  be  accounted  for  by  the  various  races  having 
similar  inventive  or  mental  powers.     The  same  observation 

*Tylors  "  Early  History  of  Mankind,"  1865;  with  respect  to  ges- 
ture-language, see  p.  54.  Lubbock's  •'  Prehistoric  Times,"  2d  edit,, 
1869. 

f  "  On  Analogous  Forms  of  Implements,"  in  "  Memoirs  of  Anthro- 
polog.  Soc,"  by  H.  M.  Westropp.  "The  Primitive  Inhabitants  of 
Scandinavia,"  Eng.  translat.,  edited  by  Sir  J.  Lubbock,  1868,  p.  104. 


a04  THE  DESCENT  OF  MAN. 

has  been  made  by  archaeologists  *  with  respect  to  certain 
widely-prevalent  ornaments,  such  as  zig-zags,  etc.;  and 
with  respect  to  various  simple  beliefs  and  customs,  such  as 
the  burying  of  the  dead  under  megalithic  structures.  I 
remember  observing  in  South  America,  f  that  there,  as  in 
so  many  other  parts  of  the  world,  men  have  generally 
chosen  the  summits  of  lofty  hills,  to  throw  up  piles  of 
stones,  either  as  a  record  of  some  remarkable  event,  or  for 
burying  their  dead. 

Now  when  naturalists  observe  a  close  agreement  in 
numerous  small  details  of  habits,  tastes,  and  dispositions 
between  two  or  more  domestic  races,  or  between  nearly 
allied  natural  forms,  they  use  this  fact  as  an  argument  that 
they  are  descended  from  a  common  progenitor  who  was 
thus  endowed;  and  consequently  that  all  should  be  classed 
under  the  same  species.  The  same  argument  may  be 
applied  with  much  force  to  the  races  of  man. 

As  it  is  improbable  that  the  numerous  and  unimportant 
points  of  resemblance  between  the  several  races  of  man  in 
bodily  structure  and  mental  faculties  (I  do  not  here  refer  to 
similar  customs)  should  all  have  been  independently 
acquired,  they  must  have  been  inherited  from  progenitors 
who  had  these  same  characters.  We  thus  gain  some  insight 
into  the  early  state  of  man,  before  he  had  spread  step  by 
step  over  the  face  of  the  earth.  The  spreading  of  man  to 
regions  widely  separated  by  the  sea,  no  doubt,  preceded  any 
great  amount  of  divergence  of  character  in  the  several 
races;  for  otherwise  we  should  sometimes  meet  with  the 
same  race  in  distinct  continents;  and  this  is  never  the  case. 
Sir  J.  Lubbock,  after  comparing  the  arts  now  practiced  by 
savages  in  all  parts  of  the  world,  specifies  those  which  man 
could  not  have  known,  when  he  first  wandered  from  his 
original  birthplace;  for  if  once  learned  they  would  never 
have  been  forgotten.  |  He  thus  shows  that  ^^the  spear, 
which  is  but  a  development  of  the  knife-point,  and  the 
club,  which  is  but  a  long  hammer,  are  the  only  things  left.^' 
He  admits,  however,  that  the  art  of  making  fire  probably 
had  been  already  discovered,  for  it  is  common  to  all  the 

*Westropp,  "  On  Cromleclis, "  etc.,  "Journal  of  Ethnological  Soc," 
as  given  in  "  Scientific  Opinion,"  June  2,  1869,  p.  3. 

f  "Journal  of  Researches;  Voyage  of  the  *  Beagle,'  "  p.  46. 
X  "Prehistoric  Times,"  1869,  p.  574. 


THE  RAGES  OF  MAN.  205 

races  now  existing,  and  was  known  to  the  ancient  cave- 
inhabitants  of  Europe.  Perhaps  the  art  of  making  rude 
canoes  or  rafts  was  likewise  known;  but  as  man  existed  at  a 
remote  epoch,  when  the  land  in  many  places  stood  at  a  very 
different  level  to  what  it  does  now,  he  would  have  been  able, 
without  the  aid  of  canoes,  to  have  spread  widely.  Sir  J. 
Lubbock  further  remarks  how  improbable  it  is  that  oui 
earliest  ancestors  could  have  *'  counted  as  high  as  ten,  con- 
;^idering  that  so  many  races  now  in  existence  cannot  get 
beyond  four."  Nevertheless,  at  this  early  period,  the  intel- 
lectual and  social  faculties  of  man  could  hardly  have  been 
inferior  in  any  extreme  degree  to  those  possessed  at  present , 
by  the  lowest  savages;  otherwise  primeval  man  could  not  \ 
have  been  so  eminently  successful  in  the  struggle  for  life, 
as  proved  by  his  early  and  wide  diffusion.  ^ 

From  the  fundamental  differences  between  certain  lan- 
guages, some  philologists  have  inferred  that  when  man  first 
became  widely  diffused,  he  was  not  a  speaking  animal;  but 
it  may  be  suspected  that  languages,  far  less  perfect  than 
any  now  spoken,  aided  by  gestures,  might  have  been  used, 
and  yet  have  left  no  traces  on  subsequent  and  more  highly- 
de\ eloped  tongues.  Without  the  use  of  some  language, 
however  imperfect,  it  appears  doubtful  whether  man's  intel- 
lect could  have  risen  to  the  standard  implied  by  his  domi- 
nant position  at  an  early  period. 

Whether  primeval  man,  when  he  possessed  but  few  arts, 
and  those  of  the  rudest  kind,  and  when  his  power  of  lan- 
guage was  extremely  imperfect,  would  have  deserved  to  be 
called  man,  must  depend  on  the  definition  which  we 
employ.  In  a  series  of  forms  graduating  insensibly  from 
some  ape-like  creature  to  man  as  he  now  exists,  it  would  be 
impossible  to  fix  on  any  definite  point  when  the  term 
"man"  ought  to  be  used.  But  this  is  a  matter  of  very 
little  importance.  So  again,  it  is  almost  a  matter  of  indif- 
ference whether  the  so-called  races  of  man  are  thus  desig- 
nated, or  are  ranked  as  species  or  sub-species;  but  the  latter 
term  appears  the  more  appropriate.  Finally,  we  may  con- 
clude that  when  the  principle  of  evolution  is  generally 
accepted,  as  it  surely  will  be  before  long,  the  dispute 
between  the  monogenists  and  the  polygenists  will  die  a  silent 
and  unobserved  death. 

One  other  question  ought  not  to  be  passed  over  without 


206  THE  DESCENT  OF  MAN. 

notice,  namely,  whether,  as  is  sometimes  assumed,  each 
sub-species  or  race  of  man  has  sprung  from  a  single  pair  of 
progenitors.  With  our  domestic  animals  a  new  race  can 
readily  be  formed  by  carefully  matching  the  varying  off- 
spring from  a  single  pair,  or  even  from  a  single  individual 
possessing  some  new  character;  but  most  of  our  races  have 
been  formed,  not  intentionally  from  a  selected  pair,  but 
unconsciously  by  the  preservation  of  many  individuals 
which  have  varied,  however  slightly,  in  some  useful  or 
desired  manner.  If  in  one  country  stronger  and  heavier 
liorses,  and  in  another  country  lighter  and  fleeter  ones,  were 
habitually  preferred,  we  may  feel  sure  that  two  distinct 
sub-breeds  would  be  produced  in  the  course  of  time,  with- 
out any  one  pair  having  been  separated  and  bred  from,  in 
either  country.  Many  races  have  been  thus  formed,  and 
their  manner  of  formation  is  closely  analogous  to  that  of 
natural  species.  We  know,  also,  that  the  horses  taken  to  the 
Falkland  Islands  have,  during  successive  generations, 
become  smaller  and  weaker,  while  those  which  have  run 
wild  on  the  Pampas  have  acquired  larger  and  coarser  heads; 
and  such  changes  are  manifestly  due,  not  to  any  one  pair, 
but  to  all  the  individuals  having  been  subjected  to  the 
same  conditions,  aided,  perhaps,  by  the  principle  of  rever- 
sion. The  new  sub-breeds  in  such  cases  are  not  descended 
from  any  single  pair,  but  from  many  individuals  which 
have  varied  in  different  degrees,  but  in  the  same  general 
manner;  and  we  may  conclude  that  the  races  of  man  have 
been  similarly  produced,  the  modifications  being  either  the 
direct  result  of  exposure  to  different  conditions,  or  the 
indirect  result  of  some  form  of  selection.  But  to  this 
latter  subject  we  shall  presently  return. 

On  the  Extinction  of  the  Races  of  Man. — The  partial  or 
complete  extinction  of  many  races  and  sub-races  of  man  is 
historically  known.  Humboldt  saw  in  South  America  a 
parrot  which  was  the  sole  living  creature  that  could  speak 
a  word  of  the  language  of  a  lost  tribe.  Ancient  monuments 
and  stone  implements  found  in  all  parts  of  the  world,  about 
which  no  tradition  has  been  preserved  by  the  present 
inhabitants,  indicate  much  extinction.  Some  small  and 
broken  tribes,  remnants  of  former  races,  still  survive  in 
isolated  and  generally  mountainous  districts.     In  Europe 


THE  RACES  OF  MAN.  207 

the  ancient  races  were  all,  according  to  Schaaffhausen,* 
'Mower  in  the  scale  than  the  rudest  living  savages ;"  they 
must  therefore  have  differed,  to  a  certain  extent,  from  any 
existing  race.  The  remains  described  by  Prof.  Broca  from 
Les  Eyzies,  though  they  unfortunately  appear  to  have 
belonged  to  a  single  family,  indicate  a  race  with  a  most 
singular  combination  of  low  or  simious,  and  of  high  char- 
acteristics. This  race  is  '-'entirely  different  from  any 
other,  ancient  or  modern,  that  we  have  heard  of."f  It 
differed,  therefore,  from  the  quaternary  race  of  the  caverns 
of  Belgium. 

Man  can  long  resist  conditions  which  appear  extremely 
unfavorable  for  his  existence.  %  He  has  long  lived  in  the 
extreme  regions  of  the  north,  with  no  wood  for  his  canoes 
or  implements,  and  with  only  blubber  as  fuel  and  melted 
snow  as  drink.  In  the  southern  extremity  of  America  the 
Fuegians  survive  without  the  protection  of  clothes,  or  of 
any  building  worthy  to  be  called  a  hovel.  In  South  Africa 
the  aborigines  wander  over  arid  plains,  where  dangerous 
beasts  abound.  Man  can  withstand  the  deadly  influence 
of  the  Terai  at  the  foot  of  the  Himalaya  and  the  pestilen- 
tial shores  of  tropical  Africa. 

Extinction  follows  chiefly  from  the  competition  of  tribe 
with  tribe  and  race  with  race.  Various  checks  are  always 
in  action,  serving  to  keep  down  the  numbers  of  each 
savage  tribe — such  as  periodical  famines,  nomadic  habits 
and  the  consequent  deaths  of  infants,  prolonged  suckling, 
wars,  accidents,  sickess,  licentiousness,  the  stealing  of 
women,  infanticide,  and  especially  lessened  fertility.  If 
any  one  of  these  checks  increases  in  power,  even  slightly, 
the  tribe  thus  affected  tends  to  decrease  ;  and  when  of  two 
adjoining  tribes  one  becomes  less  numerous  and  less  power- 
ful than  the  other,  the  contest  is  soon  settled  by  war, 
slaughter,  cannibalism,  slavery,  and  absorption.  Even 
when  a  weaker  tribe  is  not  thus  abruptly  swept  away,  if  it 
once  begins  to  decrease,  it  generally  goes  on  decreasing 
until  it  becomes  extinct.  § 

♦Translation  in  "Anthropological  Review,"  Oct.,  1868,  p.  431. 

+  *' Transact.  Intemat.  Congress  of  Prehistoric  Arch.,"  1868,  pp. 
172-17.>.  See  also  Broca  (translation)  in  "  Anthropological  Review," 
Oct.,  1868,  p.  410. 

X  Dr.  lierland,  "  Ueber  das  Aussterben  der  Xaturvolker,"  1868,  s  82. 

^  Gerland  (ibid,  s.  13)  gives  facts  in  support  of  this  statement. 


208  THE  DESCENT  OF  MAN. 

When  civilized  nations  come  into  contact  with  barba- 
rians the  struggle  is  sliort,  except  where  a  deadly  climate 
gives  its  aid  to  the  native  race.  Of  the  causes  which  lead 
to  the  victory  of  civilized  nations  some  are  plain  and  sim- 
ple, others  complex  and  obscure.  We  can  see  that  the 
cultivation  of  the  land  will  be  fatal  in  many  ways  to  sav- 
ages, for  they  cannot,  or  will  not,  change  their  habits. 
New  diseases  and  vices  have  in  some  cases  proved  highly 
destructive;  and  it  appears  that  a  new  disease  often  causes 
much  death  until  those  who  are  most  susceptible  to  its 
destructive  influence  are  gradually  weeded  out;*  and  so  it 
may  be  with  the  evil  effects  from  spirituous  liquors,  as  well 
as  with  the  unconquerably  strong  taste  for  them  shown  by 
so  many  savages.  It  further  appears,  mysterious  as  is  the 
fact,  that  the  first  meeting  of  distinct  and  separated  people 
generates  disease,  f  Mr.  Sproat,  who  in  Vancouver  Island 
closely  attended  to  the  subject  of  extinction,  believed  that 
changed  habits  of  life,  consequent  on  the  advent  of  Euro- 
peans, induces  much  ill-health.  He  lays,  also,  great  stress 
on  the  apparently  trifling  cause  that  the  natives  become 
"  bewildered  and  dull  by  the  new  life  around  them;  they 
lose  the  motives  for  exertion  and  get  no  new  ones  in  their 
place.  ^^  J 

The  grade  of  their  civilization  seems  to  be  a  most  impor- 
tant element  in  the  success  of  competing  nations.  A  few 
centuries  ago  Europe  feared  the  inroads  of  Eastern  barba- 
rians; now  any  such  fear  would  be  ridiculous.  It  is  a  more 
curious  fact,  as  Mr.  Bagehot  has  remarked,  that  savages 
did  not  formerly  waste  away  before  the  classical  nations  as 
they  now  do  before  modern  civilized  nations;  had  they 
done  so  the  old  moralists  would  have  mused  over  the  event; 
but  there  is  no  lament  in  any  writer  of  that  period  over  the 
perishing  barbarians.  §  The  most  potent  of  all  the  causes 
of  extinction  appears  in  many  cases  to  be  lessened  fertility 

*  See  remarks  to  this  effect  in  Sir  H.  Holland's  "Medical  Notes 
and  Reflections,"  1839,  p.  390. 

fl  have  collected  ("Journal  of  Researches,  Voyage  of  the 
'Beagle,'"  p.  435)  a  good  many  cases  bearing  on  this  subject;  see 
also  Gerland,  ibid,  s.  8.  Poeppig  speaks  of  the  "  breath  of  civiliza- 
tion as  poisonous  to  savages." 

:j:Sproat,  "  Scenes  and  Studies  of  Savage  Life,"  1868,  p.  284. 

§  Bagehot,  "Physics  and  Politics,"  "Fortnightly  Review,"  April 
1,  1868,  p.  405. 


THE  RACES  OF  MAN.  209 

and  ill-health,  especially  among  the  children,  arising  from 
changed  conditions  of  life,  notwithstanding  that  the  new 
conditions  may  not  be  injurious  in  themselves.  I  am  much 
indebted  to  Mr.  H,  H.  Howorth  for  having  called  my 
attention  to  this  subject  and  for  having  given  me  informa- 
tion respecting  it.     I  have  collected  the  following  cases: 

AVhen  Tasmania  was  first  colonized  the  natives  were 
roughly  estimated  by  some  at  7,000,  and  by  others  at  20,000. 
Their  number  was  soon  greatly  reduced,  chiefly  by  fighting 
with  the  English  and  with  each  other.  After  the  famous 
hunt  by  all  the  colonists,  when  the  remaining  natives  deliv- 
ered themselves  up  to  the  government,  they  consisted  only  of 
120  individuals,*  who  were  in  1832  transported  to  Flindere 
Island.  This  island,  situated  between  Tasmania  and  Aus- 
tralia, is  forty  miles  long,  and  from  twelve  to  eighteen  miles 
broad;  it  seems  healthy,  and  the  natives  were  well  treated. 
Nevertheless,  they  suffered  greatly  in  health.  In  1834  they 
consisted  (Bonwick,  p.  250)  of  forty-seven  adult  males, 
forty-eight  adult  females,  and  sixteen  children,  or  in  all  of 
one  hundred  and  eleven  souls.  In  1835  only  one  hundred 
were  left.  As  they  continued  rapidly  to  decrease,  and  as 
they  themselves  thought  that  they  should  not  perish  so 
quickly  elsewhere,  they  were  removed  in  1847  to  Oyster 
Cove  in  the  southern  part  of  Tasmania.  They  then  con- 
sisted (Dec.  20,  1847)  of  fourteen  men,  twenty-two  women 
and  ten  children,  f  But  the  change  of  site  did  no  good. 
Disease  and  death  still  pursued  them,  and  in  18G4  one  man 
(who  died  in  1869)  and  three  elderly  women  alone  survived. 
The  infertility  of  the  women  is  even  a  more  remarkable 
fact  than  the  liability  of  all  to  ill-health  and  death.  At 
the  time  when  only  nine  women  were  left  at  Oyster  Cove 
they  told  Mr.  Bonwick  (p.  386)  that  only  two  had  ever 
borne  children;  and  these  two  had  together  produced  only 
three  children! 

With  respect  to  the  cause  of  this  extraordinary  state  of 
things  Dr.  Story  remarks  that  death  followed  the  attempts 
to  civilize  the  natives.  ^^  If  left  to  themselves  to  roam  as 
they  were  wont  and  undisturbed  they  would  have  reared 
more  children  and  there  would  have  been  less  mortality." 

*  All  the  statements  here  given  are  taken  from  "The  Last  of  the 
Tasmanians,"  by  J.  Bonwick,  1870. 

f  This  is  the  statement  of  the  Governor  of  Tasmania,  Sir  W.  Deni- 
son,  "  Varieties  of  Vjce-Hegal  Life,"  1870,  vol.  i,  p.  67. 


210  THE  Descent  otr  MAM: 

Another  car^f ill  observer  of  th^  natives,  Mr;  1])avis^  l^emarksj 
"  The  births  have  been  few  and  the  deaths  numerous. 
This  may  have  been  in  a  great  measure  owing  to  their 
change  of  living  and  food;  but  more  so  to  their  banishment 
from  the  mainhind  of  Van  Diemen's  Land  and  consequent 
depression  of  spirits  "  (Bonwick,  pp.  388,  390). 

Simihir  facts  have  been  observed  in  two  widely  different 
parts  of  Australia.  The  celebrated  explorer,  Mr.  Gregory, 
told  Mr.  Bonwick,  that  in  Queensland  '^the  want  of  repro- 
duction was  being  already  felt  with  the  blacks,  even  in  the 
most  recently  settled  parts,  and  that  decay  would  set 
in/'  Of  thirteen  aborigines  from  Shark's  Bay  who  visited 
Murchison  River,  twelve  died  of  consumption  within  three 
months.* 

The  decrease  of  the  Maories  of  New  Zealand  has  been 
carefully  investigated  by  Mr.  Fenton,  in  an  admirable 
report,  from  which  all  the  following  statements,  with  one 
exception,  are  taken,  f  The  decrease  in  number  since  1830 
is  admitted  by  every  one,  including  the  natives  themselves, 
and  is  still  steadily  progressing.  Although  it  has  hitherto 
been  found  impossible  to  take  an  actual  census  of  the 
natives,  their  numbers  were  carefully  estimated  by  resi- 
dents in  many  districts.  The  result  seems  trustworthy, 
and  shows  that  during  the  fourteen  years,  previous  to  1858, 
the  decrease  was  19.42  per  cent.  Some  of  the  tribes,  thus 
carefully  examined,  lived  above  a  hundred  miles  apart, 
some  on  the  coast,  some  inland;  and  their  means  of  sub- 
sistence and  habits  differed  to  a  certain  extent  (p.  28). 
The  total  number  in  1858  was  believed  to  be  53,700,  and 
in  1872,  after  a  second  interval  of  fourteen  years,  another 
census  was  taken,  and  the  number  is  given  as  only 
36,359,  showing  a  decrease  of  32.29  per  cent.  !  J 
Mr.  Fenton,  after  showing  in  detail  the  insufficiency  of 
the  various  causes,  usually  assigned  in  explanation  of  this 
extraordinary  decrease,  such  as  new  diseases,  the  profligacy 
of  the  women,  drunkenness,  wars,  etc.,  concludes  on 
weighty  grounds  that  it  depends  chiefly  on  the  unproduc- 

*For  these  cases  see  Bonwick's  "  Daily  Life  of  tlie  Tasmanians," 
1870,  p.  90;  and  the  "  Last  of  the  Tasmanians,"  1870,  p.  386. 

f  "  Observations  on  the  Aboriginal  Inhabitants  of  New  Zealand," 
published  by  the  Government,  1859. 

;}:  "New  Zealand,"  by  Alex.  Kennedy,  1873,  p.  47. 


TS^  HA  CiSS  OF  MA  A .  ^li 

tiveness  of  the  women  aud  on  the  extmofdinary  mortality 
of  the  young  children  (pp.  31,  34).  In  proof  of  this  he 
shows  (p.  33)  that  in  1844  there  was  one  non-adnlt  for 
every  "1.6%  adults;;  whereas  in  1858  there  was  only  one  non- 
adult  for  every  3.27  adults.  The  mortality  of  tile  adults  is 
also  great.  He  adduces  as  a  further  cause  of  the  decrease 
the  inequality  of  the  sexes;  for  fewer  females  are  born  than 
males.  To  this  latter  point,  depnending  perhaps  on  a  widely 
distinct  cause,  I  shall  return  in  a  future  chapter.  Mr. 
Fenton  contrasts  with  astonishment  the  decrease  in  New 
Zealand  with  the  increase  in  Ireland;  countries  not  very 
dissimilar  in  climate,  and  where  the  inhabitants  now  follow 
nearly  similar  habits.  The  Maories  themselves  (p.  35) 
**  attribute  their  decadence,  in  some  measure,  to  the  intro- 
duction of  new  food  and  clothing,  and  the  attendant 
change  of  habits;'^  and  it  will  be  seen,  when  we  consider 
the  influence  of  changed  conditions  on  fertility,  that  they 
are  probably  right.  The  diminution  began  between  the 
years  1830  and  1840;  and  Mr.  Fenton  shows  (p.  40)  that 
about  1830,  the  art  of  manufacturing  putrid  corn  (maize), 
by  long  steeping  in  water,  was  discovered  and  largely  prac- 
ticed ;  and  this  proves  that  a  change  of  habits  was  begin- 
ning among  the  natives,  even  when  New  Zealand  was  only 
thinly  inhabited  by  Europeans.  When  I  visited  the  Bay 
of  Islands  in  1835,  the  dress  and  food  of  the  inhabitants 
had  already  been  much  modified  ;  they  raised  potatoes, 
maize  and  other  agricultural  produce,  and  exchanged  them 
for  English  manufactured  goods  and  tobacco. 

It  is  evident  from  many  statements  in  the  life  of  Bishop 
Patteson,*  that  the  Melanesians  of  the  New  Hebrides  and 
neighboring  archipelagoes,  suffered  to  an  extraordinary 
degree  in  health,  and  perished  in  large  numbers,  when  they 
were  removed  to  New  Zealand,  Norfolk  Island  and  other 
salubrious  places,  in  order  to  be  educated  as  missionaries. 

The  decrease  of  the  native  population  of  the  Sandwich 
Islands  is  as  notorious  as  that  of  New  Zealand.  It  has 
been  roughly  estimated  by  those  best  capable  of  judging, 
that  when  Cook  discovered  the  Islands  in  1779,  the  popula- 
tion amounted  to  about  300,000.  According  to  a  loose 
census  in  1823,  the  numbers  then  were  142,050.     In  1832, 

*  *'  Life  of  J.  C.  Patteson,"  by  C.  M.  Younge,  1874;  see  more 
especially  vol.  i,  p.  530. 


212 


THE  DESCENT  OF  MAN. 


and  at  several  subsequent  periods,  an  accurate  census  was 
officially  taken,  but  I  have  been  able  to  obtain  only  the  fol- 
lowing returns: 


Annual  rate  of  decrease  per 

Native  Population. 

cent.,  assuming  it  to  have 

Year. 

been  uniform  between  the 

(Except  durins:  1832  and  1836, 

successive  censuses ;   these 

when  the  few  foreigners  in 

censuses  being  taken  at  ir- 

the islands  were  included.) 

regular  intervals. 

1832 

130,313  X 

108,579 1 

71,019; 

4.46 

1836 

2.47 

1853 

C 

0.81 

1860 

67,084 

2.18 

1866 

58,765  j 
51,531 f 

2.17 

1873 

We  here  see  that  in  the  interval  of  forty  years,  between 
1832  and  1872,  the  population  has  decreased  no  less  than 
sixty-eight  per  cent. !  This  has  been  attributed  by  most 
writers  to  the  profligacy  of  the  women,  to  former  bloody 
wars,  and  to  the  severe  labor  imposed  on  conquered  tribes 
and  to  newly  introduced  diseases,  which  have  been  on  sev- 
eral occasions  extremely  destructive.  No  doubt  these  and 
other  such  causes  have  been  highly  efficient,  and  may 
account  for  the  extraordinary  rate  of  decrease  between  the 
years  1832  and  1836;  but  the  most  potent  of  all  the  causes 
seems  to  be  lessened  fertility.  According  to  Dr.  Ruschen- 
berger  of  the  United  States  Navy,  who  visited  these  islands 
between  1835  and  1837,  in  one  district  of  Hawaii,  only 
twenty-five  men  out  of  1,134,  and  in  another  district  only 
ten  out  of  637,  had  a  family  with  as  many  as  three 
children.  Of  eighty  married  women,  only  thirty-nine  had 
ever  borne  children ;  and  "  the  official  report  gives  an 
average  of  half  a  child  to  each  married  couple  in  the 
whole  island."  This  is  almost  exactly  the  same  average  as 
with  the  Tasmanians  at  Oyster  Cove.  Jarves,  who  pub- 
lished his  history  in  1843,  says  that  ^*^  families  who  have 
three  children  are  freed  from  all  taxes;  those  having  more. 


THE  RACES  OF  MAN.  213 

are  rewarded  by  gifts  of  land  and  other  encouragements." 
This  unparalleled  enactment  by  the  government  well  shows 
how  infertile  the  race  had  become.  The  Rev.  A.  Bishop 
stated  in  the  Hawaiian  *^  Spectator  "  in  1839,  that  a  large 
proportion  of  the  children  die  at  early  ages,  and  Bishop 
Staley  informs  me  that  this  is  still  the  case,  just  as  in  New 
Zealand.  This  has  been  attributed  to  the  neglect  of  the 
children  by  the  women,  but  it  is  probably  in  large  part  due 
to  innate  weakness  of  constitution  in  the  children,  in  rela- 
tion to  the  lessened  fertility  of  their  parents.  There  is, 
moreover,  a  furtlfer^esemblance  to  the  case  of  Xew  Zeal- 
and, in  the  fact  that  there  is  a  large  excess  of  male  over 
female  births;  the  census  of  1872  gives  31,650  males  to 
25,247  females  of  all  ages,  that  is  125.36  males  for  every 
100  females;  whereas  in  all  civilized  countries  the  females 
exceed  the  males.  Xo  doubt  the  profligacy  of  the  women 
may  in  part  account  for  their  small  fertility;  but  their 
changed  habits  of  life  is  a  much  more  probable  cause,  and 
which  will  at  the  same  time  account  for  the  increased  mor- 
tality, especially  of  the  children.  The  islands  were  visited 
by  Cook  in  1779,  by  Vancouver  in  1794,  and  often  subse- 
quently by  whalers.  In  1819  missionaries  arrived,  and 
found  that  idolatry  had  been  already  abolished,  and  other 
changes  effected  by  the  king.  After  this  period  there  was 
a  rapid  change  in  almost  all  the  habits  of  life  of  the  natives, 
and  they  soon  became  ^*the  most  civilized  of  the  Pacific 
Islanders."  One  of  my  informants,  Mr.  Coan,  who  was 
born  on  the  islands,  remarks  that  the  natives  have  under- 
gone a  greater  change  in  their  habits  of  life  in  the  course 
of  fift}'  years  than  Englishmen  during  a  thousand  years. 
From  information  received  from  Bishop  Staley,  it  does 
not  appear  that  the  poorer  classes  have  ever  much  changed 
their  diet,  although  many  new  kinds  of  fruit  have  been 
introduced,  and  the  sugar-cane  is  in  universal  use.  Owing 
however,  to  their  passion  for  imitating  Europeans,  they 
altered  their  manner  of  dressing  at  an  early  period,  and 
the  use  of  alcoholic  drinks  became  very  general.  Although 
these  changes  appear  inconsiderable,  I  can  well  believe, 
from  what  is  known  with  respect  to  animals,  that  they 
might  suffice  to  lessen  the  fertility  of  the  natives.* 

*  The  foregoing  statements  are  taken  chiefly  from  the  following 
works:  "  Jarves'  History  of  the  Hawaiian  Islands,"  1843,  pp.  400- 
407.      Cheever,    "Life    in   the  tSandwich   Islands,"    1851,   p.    277. 


0.14  THE  DESCENT  OF  MAN. 

Lastly,  Mr.  Macnamara  states  *  that  the  low  and  de- 
graded inhabitants  of  the  Andaman  Islands,  on  the  eastern 
side  of  the  Gulf  of  Bengal,  are  "  eminently  susceptible  to 
any  change  of  climate;  in  fact,  take  them  away  from  their 
island  homes,  and  they  are  almost  certain  to  die,  and  that 
independently  of  diet  or  extraneous  influences. "  He  further 
states  that  the  inhabitants  of  the  Valley  of  Nepal,  which  is 
extremely  hot  in  summer,  and  also  the  various  hill-tribes 
of  India,  suffer  from  dysentery  and  fever  when  on  the 
plains;  and  they  die  if  they  attempt  to  pass  the  whole  year 
there. 

We  thus  see  that  many  of  the  wilder  races  of  man  are 
apt  to  suffer  much  in  health  when  subjected  to  changed 
conditions  or  habits  of  life  and  not  exclusively  from  being 
transported  to  a  new  climate.  Mere  alterations  in  habits, 
which  do  not  appear  injurious  in  themselves,  seem  to  have  this 
same  effect;  and  in  several  cases  the  children  are  particularly 
liable  to  suffer.  It  has  often  been  said,  as  Mr.  Macnamara 
remarks,  that  man  can  resist  with  impunity  the  greatest 
diversities  of  climate  and  other  changes;  but  this  is  true 
only  of  the  civilized  races.  Man  in  his  wild  condition 
seems  to  be  in  this  respect  almost  as  susceptible  as  his  near- 
est allies,  the  anthropoid  apes,  which  have  never  yet  sur- 
vived long,  when  removed  from  their  native  country. 

Lessened  fertility  from  changed  conditions,  as  in  the  case 
of  the  Tasmanians,  Maories,  Sandwich  Islanders,  and 
apparently  the  Australians,  is  still  more  interesting  than 
their  liability  to  ill-health  and  death;  for  even  a  slight 
degree  of  infertility,  combined  with  those  other  causes 
which  tend  to  check  the  increase  of  every  population,  would 
sooner  or  later  lead  to  extinction.  The  diminution  of  fertility 
may  be  explained  in  some  cases  by  the  profligacy  of  the 
women  (as  until  lately  with  the  Tahitians),  but  Mr.  Fenton 
has  shown  that  this  explanation  by  no  means  suffices  with 
the  New  Zealanders,  nor  does  it  with  the  Tasmanians. 

Rusclienberger  is  quoted  by  Bonwick,  "Last  of  the  Tasmanians," 
1870,  p.  378.  Bishop  is  quoted  by  Sir  E.  Belcher,  "  Voyage  Hound 
the  World,"  1843,  vol.  i,  p.  272.  I  owe  the  ensus  of  the  several 
years  to  the  kindness  of  Mr.  Coan,  at  the  request  of  Dr.  Youmans,  of 
New  York;  and  in  most  cases  I  have  compared  the  Youmans  figures 
with  those  given  in  several  of  the  above-named  works.  I  have 
omitted  the  census  for  1850,  as  I  have  seen  two  widely  different  num- 
bers given. 

*  "  The  Indian  Medical  Gazette,"  Nov.  1,  1871,  p.  240. 


THE  RACES  OF  MAN.  215 

In  the  paper  above  quoted,  Mr.  Macnamara  gives  veasons 
for  believing  that  the  inhabitants  of  districts  subj.ect  to 
malaria  are  apt  to  be  sterile;  but  this  cannot  apply  in  sev- 
eral of  the  above  cases.  Some  writers  have  suggested  that 
the  aborigines  of  islands  have  suffered  in  fertility  and 
health  from  long  continued  inter-breeding;  but  in  the  above 
cases  infertility  has  coincided  too  closely  with  the  arrival 
of  Europeans  for  us  to  admit  this  explanation.  Nor  have 
we  at  present  any  reason  to  believe  that  man  is  highly  sen- 
sitive to  the  evil  effects  of  inter-breeding,  especially  in 
areas  so  large  as  New  Zealand  and  the  Sandwich  Archi- 
pelago with  its  diversified  stations.  On  the  contrary,  it  is 
known  that  the  present  inhabitants  of  Norfolk  Island  are 
nearly  all  cousins  or  near  relations,  as  are  the  Todas  in 
India,  and  the  inhabitants  of  some  of  the  Western  Islands 
of  Scotland;  and  yet  they  seem  not  to  have  suffered  in 
fertility.  * 

A  much  more  probable  view  is  suggested  by  the  analogy 
of  the  lower  animals.  The  reproductive  system  can  be 
shown  to  be  susceptible  to  an  extraordinary  degree  (though 
why  we  know  not)  to  changed  conditions  of  life;  and  this 
susceptibility  leads  both  to  beneficial  and  to  evil  results. 
A  large  collection  of  facts  on  this  subject  is  given  in  chap- 
ter xviii,  of  volume  ii,  of  my  '^  Variation  of  Animals  and 
Plants  under  Domestication."  I  can  here  give  only  the 
briefest  abstract;  and  every  one  interested  in  the  subject 
may  consult  the  above  work.  Very  slight  changes  increase 
the  health,  vigor  and  fertility  of  most  or  all  organic  beings, 
while  other  changes  are  known  to  render  a  large  number  of 
animals  sterile.  One  of  the  most  familiar  cases  is  that  of 
tamed  elephants  not  breeding  in  India;  though  they  often 
breed  in  Ava,  where  the  females  are  allowed  to  roam  about 
the  forests  to  some  extent,  and  are  thus  placed  under  more 
natural  conditions.  The  case  of  various  American  mon- 
keys, both  sexes  of  which  have  been  kept  for  many  years 
together  in  their  own  countries,  and  yet  have  very  rarely 
or  never  bred,  is  a  more  apposite  instance,  because  of  their 
relationship  to  man.     It  is  remarkable  how  slight  a  change 

*0n  the  close  relationship  of  tlie  Norfolk  Islanders,  see  Sir  W, 
Denison,  "Varieties  of  Vice-Kegal  liife,"  vol.  i,  1870,  p.  410.  For 
tlie  Todas,  see  Col.  Marshall's  work,  1873,  p.  110.  For  the  Western 
Islands  of  Scotland.  Dr.  Mitchell,  "Edinburgh  Medical  Journal," 
March  to  June,  1865. 


216  THE  DESCENT  OF  MAN. 

in  the  conditions  often  induces  sterility  in  a  wild  animal 
when  captured;  and  this  is  the  more  strange  as  all  our 
domesticated  animals  have  become  more  fertile  than  they 
were  in  a  state  of  nature;  and  some  of  them  can  resist  the 
most  unnatural  conditions  with  undiminished  fertility.* 
Certain  groups  of  animals  are  much  more  liable  than  others 
to  be  affected  by  captivity;  and  generally  all  the  species  of 
the  same  group  are  affected  in  the  same  manner.  But 
sometimes  a  single  species  in  a  group  is  rendered  sterile, 
while  the  others  are  not  so;  on  the  other  hand,  a  single 
species  may  retain  its  fertility  while  most  of  the  others  fail 
to  breed.  The  males  and  females  of  some  species  when 
confined,  or  when  allowed  to  live  almost  but  not  quite  free, 
in  their  native  country  never  unite;  others  thus  circum- 
stanced frequently  unite  but  never  produce  offspring; 
others  again  produce  some  offspring,  but  fewer  than  in  a 
state  of  nature;  and  as  bearing  on  the  above  cases  of  man 
it  is  important  to  remark  that  the  young  are  apt  to  be 
weak  and  sickly,  or  malformed,  and  to  perish  at  an  early 
age. 

Seeing  how  general  is  this  law  of  the  susceptibility  of  the 
reproductive  system  to  changed  conditions  of  life,  and  that 
it  holds  good  with  our  nearest  allies,  the  Quadrumana,  I 
can  hardly  doubt  that  it  applies  to  man  in  his  primeval  state. 
Hence,  if  savages  of  any  race  are  induced  suddenly  to  change 
their  habits  of  life  they  become  more  or  less  sterile,  and 
their  young  offspring  suffer  in  health  in  the  same  manner 
and  from  the  same  cause  as  do  the  elephant  and  hunting- 
leopard  in  India,  many  monkeys  in  America,  and  a  host 
of  animals  of  all  kinds  on  removal  from  their  natural 
conditions. 

We  can  see  why  it  is  that  aborigines,  who  have  long 
inhabited  islands,  and  who  must  have  been  long  exposed  to 
nearly  uniform  conditions,  should  be  specially  affected  by 
any  change  in  their  habits,  as  seems  to  be  the  case.  Civil- 
ized races  can  certainly  resist  changes  of  all  kinds  far 
better  than  savages  ;  and  in  this  respect  they  resemble 
domesticated  animals,  for  though  the  latter  sometimes 
suffer  in  health  (for  instance  European  dogs  in  India),  yet 
they    are    rarely    rendered    sterile,    though    a   few   such 

*For  tlie  evidence  on  this  liead,  see  "  Variation  of  Animals,"  etc., 
vol.  ii,  p.  111. 


THE  RAGES  OF  MAN.  217 

instances  have  been  recorded.*  The  immunity  of  civilized 
races  and  domesticated  animals  is  probably  due  to  their 
having  been  subjected  to  a  greater  extent,  and,  therefore, 
having  grown  somewhat  more  accustomed,  to  diversified  or 
varying  conditions,  than  the  majority  of  wild  animals;  and 
to  their  having  formerly  immigrated  or  been  carried  from 
country  to  country,  and  to  different  families  or  sub-races 
having  inter-crossed.  It  appears  that  a  cross  with  civilized 
races  at  once  gives  to  an  aboriginal  race  an  immunity  from 
the  evil  consequences  of  changed  conditions.  Thus  the 
crossed  offspring  from  the  Tahitians  and  English,  when 
settled  in  Pitcairn  Island,  increased  so  rapidly  that  the 
island  was  soon  overstocked;  and  in  June,  1856,  they  were 
removed  to  Norfolk  Island.  They  then  consisted  of 
60  married  persons  and  134  children,  making  a  total  of 
194.  Here  they  likewise  increased  so  rapidly  that, 
although  16  of  them  returned  to  Pitcairn  Island  in  1859, 
they  numbered  in  January,  1868,  300  souls;  the  males  and 
females  being  in  exactly  equal  numbers.  What  a  contrast 
does  this  case  present  with  that  of  the  Tasmanians;  the 
Norfolk  Islanders  increased  in  only  twelve  and  a  half  years 
from  194  to  200;  whereas  the  Tasmanians  decreased  during 
15  years  from  120  to  46,  of  which  latter  number  only  10 
were  children,  f 

So  again  in  the  interval  between  the  census  of  1866  and 
1872  the  natives  of  full  blood  in  the  Sandwich  Islands 
decreased  by  8,081,  while  the  half-castes,  who  are  believed 
to  be  healthier,  increased  by  847;  but  I  do  not  know 
whether  the  latter  number  includes  the  offsprings  from 
the  half-castes,  or  only  the  half-castes  of  the  first  genera- 
tion. 

The  cases  which  I  have  here  given  all  relate  to  aborigines, 
who  have  been  subjected  to  new  conditions  as  the  result  of 
the  immigration  of  civilized  men.  But  sterility  and  ill- 
health  would  probably  follow  if  savages  were  compelled  by 
any  cause,  such  as  the  inroad  of  a  conquering  tribe,  to 
desert  their  homes  and  to  change  their  habits.     It  is  an 

*"  Variation  of  Animals,"  etc.,  vol.  ii,  p.  16. 

f  These  details  are  taken  from  "  The  Mutineers  of  the  '  Bounty,' " 
by  Lady  Belcher,  1870;  and  from  "  Pitcairn  Island,"  ordered  to  be 
printed  by  the  House  of  Conunons,  May  29,  1868.  The  following 
statements  about  the  Sandwich  Islanders  are  from  the  "Honolulu 
Gazette,"  and  from  Mr.  Coan. 


218  THE  DEBCKNT  OF  MAN. 

interesting  circumstance  tlifit  the  chief  check  to  wild  ani- 
mals becoming  domesticated,  which  implies  the  power  of 
their  breeding  freely  when  first  captured,  and  one  chief 
check  to  wikl  men,  when  brought  into  contact  with  civil- 
ization, surviving  to  form  a  civilized  race,  is  the  same, 
namely,  sterility  from  cjumged  conditions  of  life. 

Finally,  although  the  gradual  decrease  and  ultimate 
extinction  of  the  races  of  man  is  a  highly  com[)lex 
problem,  depending  on  many  causes  which  differ  in 
different  places  and  at  different  times  ;  it  is  the  same 
problem  as  that  presented  by  the  extinction  of  one  of 
the  higher  animals — of  the  fossil  horse,  for  instance,  which 
disappeared  from  South  America,  soon  afterward  to  be 
replaced,  within  the  same  districts,  by  countless  troups  of 
the  Spanish  horse.  The  New  Zealander  seems  conscious  of 
this  parallelism,  for  he  compares  his  future  fate  with  that 
of  the  native  rat  now  almost  exterminated  by  the  Euro- 
pean rat.  Though  the  difficulty  is  great  to  our  imagi- 
nation, and  really  great,  if  we  wish  to  ascertain  the  precise 
causes  and  their  manner  of  action,  it  ought  not  to  be  so  to 
our  reason,  as  long  as  we  keep  steadily  in  mind  that  the 
increase  of  each  species  and  each  race  is  constantly  checked 
in  various  ways;  so  that  if  any  new  check,  even  a  slight 
one,  be  superadded,  the  race  will  surely  decrease  in  number; 
and  decreasing  numbers  will  sooner  or  later  lead  to  extinc- 
tion; the  end,  in  most  cases,  being  promptly  determined 
by  the  inroads  of  conquering  tribes. 

On  the  Formation  of  the  Races  of  Man. — In  some  cases 
the  crossing  of  distinct  races  has  led  to  the  formation  of  a 
new  race.  The  singular  fact  that  the  Europeans  and  Hin- 
doos, who  belong  to  the  same  Aryan  stock  and  speak  a 
language  fundamentally  the  same,  differ  widely  in  appear- 
ance, while  Europeans  differ  but  little  from  Jews,  who 
belong  to  the  Semitic  stock  and  speak  quite  another  lan- 
guage, has  been  accounted  for  by  Bi'oca,*  through  certain 
Aryan  branches  having  been  largely  crossed  by  indigenous 
tribes  during  their  wide  diffusion.  When  two  races  in 
close  contact  cross  the  first  result  is  a  heterogeneous  mix- 
ture; thus  Mr.  Hunter,  in  describing  the  Santali  or  hill- 


*"0n  Anthropology,"  translation  "  Anthropolog.  Review,"  Jan., 

1868,  p.  38. 


THE  RAGES  OF  MAN,  ^10 

tribes  of  India,  says  that  hundreds  of  imperceptible  grada- 
tions may  be  traced  '^  from  the  bhick,  squat  tribes  of  the 
mountains  to  the  tall  olive-colored  Brahman,  with  his  intel- 
lectual brow,  calm  eyes,  and  high  but  narrow  head;"  so 
that  it  is  necessary  in  courts  of  justice  to  ask  the  wit- 
nesses whether  they  are  Santalis  or  Hindoos.*  Whether 
a  heterogeneous  people,  such  as  the  inhabitants  of  some 
of  the  Polynesian  islands,  formed  by  the  crossing  of  two 
distinct  races,  with  few  or  no  pure  members  left,  would 
ever  become  homogenous,  is  not  known  from  direct  evi- 
dence. But  as  with  our  domesticated  animals,  a  cross- 
breed can  certainly  be  fixed  and  made  uniform  by  careful 
selection!  in  the  course  of  a  few  generations,  we  may  infer 
that  the  free  intercrossing  of  a  heterogeneous  mixture 
during  a  long  descent  would  supply  the  place  of  selection 
and  overcome  any  tendency  to  reversion  ;  so  that  the 
crossed  race  would  ultimately  become  homogeneous, 
though  it  might  not  partake  in  an  equal  degree  of  the 
characters  of  the  two  parent-races. 

Of  all  the  differences  between  the  races  of  man,  the  color 
of  the  skin  is  the  most  conspicuous  and  one  of  the  best 
marked.  It  was  formerly  thought  that  differences  of  this 
kind  could  be  accounted  for  by  long  exposure  to 
different  climates ;  but  Pallas  first  showed  that  this 
is  not  tenable  and  he  has  since  been  followed 
by  almost  all  anthropologists.  J  This  view  has  been 
rejected  chiefly  because  the  distribution  of  the  variously 
colored  races,  most  of  whom  must  have  long  inhabited  their 
present  homes,  does  not  coincide  with  corresponding  dif- 
ferences of  climate.  Some  little  weight  may  be  given  to 
such  cases  as  that  of  the  Dutch  families,  who,  as  we  hear  on 
excellent  authority, §  have  not  undergone  the  least  change 
of  color  after  residing  for  three  centuries  in  S.  Africa. 
An  argument  on   the  same  side  may  likewise  be  drawn 

*  "  The  Annals  of  Rural  Bengal,"  1868,  p.  134. 

f  "  The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  p.  95. 

^: Pallas,  "Act.  Acad.  St.  Petersburg,"  1780,  part  ii,  p.  69.  He 
was  followed  by  Rudolphi,  in  his  "  Beytrage  zur  Anthropologic," 
1812.  An  excellent  summary  of  the  evidence  is  given  by  Godron, 
"  De  I'Espece,"  1859,  vol.  ii,  p.  246,  etc. 

§  Sir  Andrew  Smith,  as  quoted  by  Knox,  "  Races  of  Man,"  1850, 
p.  473. 


2^0  fiSE  DESCENT  OF  MAN. 

from  th6  iiniform  appearance  in  various  parts  of  the  world 
of  gypsies  and  Jews,  though  the  uniformity  of  the  Litter 
has  been  somewhat  exaggerated.*  A  very  damp  or  a  very 
dry  atmosphere  has  been  supposed  to  be  more  influential  in 
modifying  the  color  of  the  skin  than  mere  heat;  but  Jis 
D'Orbigny  in  South  America,  and  Livingstone  in  Africa, 
arrived  at  diametrically  opposite  conclusions  with  respect  to 
dampness  and  dryness,  any  conclusion  on  this  head  must 
be  considered  as  very  doubtful,  f 

Various  facts,  which  I  have  given  elsewhere,  prove  that 
the  color  of  the  skin  and  hair  is  sometimes  correlated  in  a 
surprising  manner  with  a  complete  immunity  from  the 
action  of  certain  parasites.  Hence  it  occurred  to  me,  that 
negroes  and  other  dark  races  might  have  acquired  tlicir 
dark  tints  by  the  darker  individuals  escaping  from  the 
deadly  influence  of  the  miasma  of  their  native  countries, 
during  a  long  series  of  generations. 

I  afterward  found  that  this  same  idea  had  long  ago 
occurred  to  Dr.  Wells.  J;  It  has  long  been  known  that 
negroes,  and  even  mulattoes  are  almost  completely  exempt 
from  the  yellow  fever,  so  destructive  in  tro^^ical  America.  § 
They  likewise  escape  to  a  large  extent  the  fatal  intermit- 
tent fevers  that  prevail  along  at  least  2,000  miles  of  the 
shores  of  Africa,  and  which  annually  cause  one-fifth  of  the 
white  settlers  to  die  and  another  fifth  to  return  home 
invalided.  ||  This  immunity  in  the  negro  seems  to  be  partly 
inherent,  depending  on  some  unknown  peculiarity  of  con- 
stitution and  partly  the  result  of  acclimatization.  Pouchetl" 
states  that  the  negro  regiments  recruited  near  the  Soudan 

*  See  De  Quatrefages  on  this  head,  "Revue  des  Cours  Scien- 
tifiques,"  Oct.  17,  1868,  p.  731. 

f  Livingstone's  "  Travels  and  Researches  in  S.  Africa,"  1857,  pp. 
338,  339.  D'Orbigny,  as  quoted  by  Godron,  "  De  I'Espece,"  vol.  ii, 
p.  266. 

X  See  a  paper  read  before  the  Royal  Soc.  in  1813  and  published  in 
his  Essays  in  1818.  I  have  given  an  account  of  Dr.  Wells'  views  in 
the  Historical  Sketch  (p.  16)  to  my  "  Origin  of  Species."  Various 
cases  of  color  correlated  with  constitutional  peculiarities  are  given  in 
my  "  Variation  of  Animals  under  Domei^tication,"  vol.  ii,  pp.  227,335. 

§  See,  for  instance,  Nott  and  (Jliddon,  "  Ty])es  of  Mankind,"  p.  68. 

I  Maj.  Tulloch,  in  a  paper  read  before  the  Statistical  Society,  April 
20,  1840,  and  given  in  the  "  Athen«uin,"  1840,  p.  353. 
.  Y'  The  Plurality  of  the  Human  Race  "  (translat.),  1864,  p.  60. 


THE  RACES  OF  MAN.  221 

and  borrowed  from  the  Viceroy  of  Egypt  for  the  Mexican 
war  escaped  the  yellow  fever  almost  equally  with  the 
negroes  originally  brought  from  various  parts  of  Africa  and 
accustomed  to  the  climate  of  the  AVest  Indies.  That 
acclimatization  plays  a  part  is  shown  by  the  many  cases  in 
which  negroes  have  become  somewhat  liable  to  tropical 
fevers,  after  having  resided  for  some  time  in  a  colder 
climate.*  The  nature  of  the  climate  under  which  the 
white  races  have  long  resided,  likewise  has  some  influence 
on  them;  for  during  the  fearful  epidemic  of  yellow  fever 
in  Demerara  during  1837  Dr.  Blair  found  that  the  death- 
rate  of  the  immigrants  was  proportional  to  the  latitude  of 
the  country  whence  they  had  come.  With  the  negro  the 
immunity,  as  far  as  it  is  the  result  of  acclimatization, 
implies  exposure  during  a  prodigious  length  of  time;  for 
the  aborigines  of  tropical  America  who  have  resided  there 
from  time  imnjemorial  are  not  exempt  from  yellow  fever; 
and  the  Rev.  H.  B.  Tristram  states  that  there  are  districts 
in  Northern  Africa  which  the  native  inhabitants  are  com- 
pelled annually  to  leave,  though  the  negroes  can  remain 
with  safety. 

That  the  immunity  of  the  negro  is .  in  any  degree  corre- 
lated with  the  color  of  his  skin  is  a  mere  conjecture;  it 
may  be  correlated  with  some  difference  in  his  blood,  nerv- 
ous system  or  other  tissues.  Nevertheless,  from  the  facts 
above  alluded  to  and  from  some  connection  apparently  ex- 
isting between  complexion  and  a  tendency  to  consumption, 
the  conjecture  seemed  to  me  not  improbable.  Conse- 
quently I  endeavored,  with  but  little  success,!  to  ascertain 

*  Quatrefages,  "  Unite  de  I'Espece  Humaine,"  1861,  p.  205.  Waitz, 
"Introduct.  to  Anthropology,"  translat. ,  vol.  i,  1863,  p.  124.  Liv- 
ingsto'^e  gives  analogous  cases  in  his  "  Travels." 

f  In  the  spring  of  1863  I  obtained  permission  from  the  Director- 
General  of  the  Medical  Department  of  the  Army  to  transmit  to  the 
surgeons  of  the  various  regiments  on  foreign  service  a  blank  table, 
with  the  following  appended  remarks,  but  I  have  received  no 
returns:  "As  several  well-marked  cases  have  been  recorded  with 
our  domestic  animals  of  a  relation  between  the  color  of  the  dermal 
appendages  and  the  constitution;  and  it  being  notorious  that  there  is 
some  limited  degree  of  relation  between  the  color  of  the  races  of  man 
and  the  climate  inhabited  by  them;  the  following  investigation  seems 
worth  consideration.  Namely,  whether  there  is  any  relation  in  Euro- 
peans between  the  color  of  their  hair  and  their  liability  to  the  diseases 
of  tropical  countries.  If  the  surgeons  of  the  several  regiments,  when 
Stationed  in  unhealthy  tropical  districts,  would  b^  so  good  as  first  to 


222  THE  DESCENT  OF  MAN. 

how  far  it  holds  good.  The  late  Dr.  Daniell,  who  had 
long  lived  on  the  west  coast  of  Africa,  told  me  that  he  did 
not  believe  in  any  such  relation.  He  was  himself  unusually 
fair  and  had  withstood  the  climate  in  a  wonderful  manner. 
When  he  first  arrived  as  a  boy  on  the  coast  an  old  and  ex- 
perienced negro  chief  predicted  from  his  appearance  that 
this  would  prove  the  case.  Dr.  Nicholson,  of  Antigua, 
after  having  attended  to  this  subject,  writes  to  me  that 
dark-colored  Europeans  escape  the  yellow  fever  more  than 
those  that  are  light  colored.  Mr.  J.  M.  Harris  altogether 
denies  that  Europeans  with  dark  hair  withstand  a  hot  cli- 
mate better  than  other  men;  on  the  contrary,  experience 
has  taught  him  in  making  a  selection  of  men  for  service  on 
the  coast  of  Africa  to  choose  those  with  red  hair.*  As  far, 
therefore,  as  these  slight  indications  go,  there  seems  no 
foundation  for  the  hypothesis,  that  blackness  has  resulted 
from  the  darker  and  darker  individuals  having  survived 
better  during  long  exposure  to  fever-generating  miasma. 
Dr.  Sharpe  remarks,  f  that  a  tropical  sun,  which  burns 

count,  as  a  standard  of  comparison,  how  many  men,  in  the  force 
whence  the  sick  are  drawn,  have  dark  and  light-colored  hair  and 
hair  of  intermediate  or  doubtful  tints;  and  if  a  similar  account  were 
kept  by  the  same  medical  gentlemen  of  all  the  men  who  suffered 
from  malarious  and  yellow  fevers,  or  from  dysentery,  it  would  soon 
be  apparent,  after  some  thousand  cases  had  been  tabulated,  whether 
there  exists  any  relation  between  the  color  of  the  hair  and  constitu- 
tional liability  to  tropical  diseases.  Perhaps  no  such  relation  would 
be  discovered,  but  the  investigation  is  well  worth  making.  In  case 
any  positive  result  were  obtained  it  might  be  of  some  practical  use 
in  selecting  men  for  any  particular  service.  Theoretically  the  result 
would  be  of  high  interest,  as  indicating  one  means  by  which  a  race 
of  men  inhabiting  from  a  remote  period  an  unhealthy  tropical  cli- 
mate, might  have  become  dark-colored  by  the  better  preservation  of 
dark-haired  or  dark-complexioned  individuals  during  a  long  succes- 
sion of  generations." 

*"  Anthropological  Review,"  Jan.,  1866,  p.  21.  Dr.  Sharpe  also 
says,  with  respect  to  India  ("  Man  a  Special  Creation,"  1873,  p.  118), 
"  that  it  has  been  noticed  by  some  medical  officers  that  Europeans 
with  light  hair  and  florid  complexions  suffer  less  from  diseases  of 
tropical  countries  than  persons  with  dark  hair  and  sallow  complex 
ions;  and,  so  far  as  I  know,  there  appear  to  be  good  grounds  for 
this  remark."  On  the  other  hand,  Mr.  Heddle,  of  Sierra  Leone. 
"  who  has  had  more  clerks  killed  under  him  than  any  other  man," 
by  the  climate  of  the  West  African  Coast  (W.  Reade,  "African 
Sketch  Book,"  vol.  ii,  p.  522),  holds  a  directly  opposite  view,  as  doe^ 
Capt.  Burton. 

t  "Man  a  Special  Creation,"  1873,  p.  H9, 


THE  RACES  OF  MAN,  223 

and  blisters  a  white  skin,  does  not  injure  a  black  one  at  all; 
and,  as  he  adds,  this  is  not  due  to  habit  in  the  individual, 
for  children  only  six  or  eight  months  old  are  often  carried 
about  naked,  and  are  not  affected.  I  have  been  assured  by 
a  medical  man  that  some  years  ago  during  each  summer, 
but  not  during  the  winter,  his  hands  became  marked  with 
light  brown  patches,  like,  although  larger  than  freckles, 
and  that  these  patches  were  never  affected  by  sun-burning, 
while  the  white  parts  of  his  skin  have  on  several  occasions 
been  much  inflamed  and  blistered.  With  the  lower  ani- 
mals there  is,  also,  a  constitutional  difference  in  liability  to 
the  action  of  the  sun  between  those  parts  of  the  skin 
clothed  with  white  hair  and  other  parts.*  Whether  the 
saving  of  the  skin  from  being  thus  burned  is  of  sufficient 
importance  to  account  for  a  dark  tint  having  been  gradually 
acquired  by  man  through  natural  selection  I  am  unable  to 
judge.  If  it  be  so,  we  should  have  to  assume  that  the 
natives  of  tropical  America  have  lived  there  for  a  much 
shoiler  time  than  the  negroes  in  Africa,  or  the  Papuans  in 
the  southern  parts  of  the  Malay  Archipelago,  just  as  the 
lighter-colored  Hindoos  have  resided  in  India  for  a  shorter 
time  than  the  darker  aborigines  of  the  central  and  southern 
parts  of  the  peninsula. 

Although  with  our  present  knowledge  we  cannot  account 
for  the  differences  of  color  in  the  races  of  man,  through 
any  advantage  thus  gained,  or  from  the  direct  action  of 
climate;  yet  we  must  not  quite  ignore  the  latter  agency, 
for  there  is  good  reason  to  believe  that  some  inherited  effect 
is  thus  produced,  f 

We  have  seen  in  the  second  chapter  that  the  conditions 
of  life  affect  the  development  of  the  bodily  frame  in  a 
direct  manner,  and  that  the  effects  are  transmitted.  Thus, 
as  is  generally  admitted,  the  European  settlers  in  the 
United   States  undergo  a  slight  but  extraordinary  rapid 

*  "  Variation  of  Animals  and  Plants  under  Domestication,"  vol.  ii, 
pp.  336,  337. 

f  See,  for  instance,  Quatrefages  ("  Revue  des  Cours  Scientifiques," 
Oct.  10,  1868,  p.  724)  on  the  effects  of  residence  in  Abyssinia  and 
Arabia,  and  other  analogous  cases.  Dr.  Rolle  ("  Der  Mensch,  seine 
Abstammung,"  etc.,  1865,  s.  99)  states,  on  the  authority  of  Khanikof, 
that  the  greater  number  of  German  families  settled  in  Georgia  have 
acquired  in  the  course  of  two  generations  dark  hair  and  eyes.  Mr. 
D.  Forbes  informs  me  that  the  Quichuas  in  the  Andes  vary  greatly  in 
color,  according  to  the  position  of  the  valleys  inhabited  by  them. 


224  THE  DESCENT  OF  MAN. 

change  of  appearance.  Their  bodies  and  limbs  become 
elongated;  and  I  hear  from  Col.  Bernys  that  during  the 
late  war  in  the  United  States,  good  evidence  was  afforded 
of  this  fact  by  the  ridiculous  appearance  presented  by  the 
German  regiments  when  dressed  in  ready-made  clothes 
manufactured  for  the  American  market,  and  which  were 
much  too  long  for  the  men  in  every  way.  There  is,  also,  a 
considerable  body  of  evidence  showing  that  in  the  Southern 
States  the  house  slaves  of  the  third  generation  present  a 
markedly  different  appearance  from  the  field  slaves.* 

If,  however,  we  look  to  the  races  of  man  as  distributed 
over  the  world  we  must  infer  that  their  characteristic  dif- 
ferences cannot  be  accounted  for  by  the  direct  action  of 
different  conditions  of  life,  even  after  exposure  to  them  for 
an  enormous  period  of  time.  The  Esquimaux  live  exclu- 
sively on  animal  food;  they  are  clothed  in  thick  fur,  and 
are  exposed  to  intense  cold  and  to  prolonged  darkness;  yet 
they  do  not  differ  in  any  extreme  degree  from  the  inhabit- 
ants of  Southern  China,  who  live  entirely  on  vegetable 
food  and  are  exposed  almost  naked  to  a  hot,  glaring  cli- 
mate. The  unclothed  Fuegians  live  on  the  marine  pro- 
ductions of  their  inhospitable  shores ;  the  Botocudos  of 
Brazil  wander  about  the  hot  forests  of  the  interior  and  live 
chiefly  on  vegetable  productions;  yet  these  tribes  resemble 
each  other  so  closely  that  the  Fuegians  on  board  the 
"  Beagle"  were  mistaken  by  some  Brazilians  for  Botocudos. 
The  Botocudos  again,  as  well  as  the  other  inhabitants  of 
tropical  America,  are  wholly  different  from  the  negroes 
who  inhabit  the  opposite  shores  of  the  Atlantic,  are  ex- 
posed to  a  nearly  similar  climate  and  follow  nearly  the 
same  habits  of  life. 

Nor  can  the  differences  between  the  races  of  man  be  ac- 
counted for  by  the  inherited  effects  of  the  increased  or 
decreased  use  of  parts  except  to  a  quite  insignificant  degree. 
Men  who  habitually  live  in  canoes  may  have  their  legs 
somewhat  stunted;  those  who  inhabit  lofty  regions  may 
have  their  chests  enlarged;  and  those  who  constantly  use 
certain  sense  organs  may  have  the  cavities  in  which  they 
are  lodged  somewhat  increased  in  size,  and  their  features 
consequently  a  little  modified.     With  civilized  nations  the 

*  Harlan,  "Medical  Researches,"  p.  533,  Quatrefages  ("Unite  de 
I'Espece  Humaine,"  1861,  p.  128)  has  collected  much  evidence  on  this 
head. 


THE  RACES  OF  MAN,  225 

reduced  size  of  the  jaws  from  lessened  use — the  habitual 
play  of  different  muscles  serving  to  express  different  emo- 
tions— and  the  increased  size  of  the  brain  from  greater 
intellectual  activity  have  together  produced  a  considerable 
effect  on  their  general  appearance  when  compared  with 
savages.  *  Increased  bodily  stature,  without  any  corre- 
sponding increase  in  the  size  of  the  brain,  may  (Judging 
from  the  previously  adduced  case  of  rabbits),  have  given 
to  some  races  an  elongated  skull  of  the  dolichocephalic 
type. 

Lastly,  the  little  understood  principle  of  correlated  de- 
velopment has  sometimes  come  into  action,  as  in  the  case 
of  great  muscular  development  and  strongly  projecting 
supra-orbital  ridges.  The  color  of  the  skin  and  hair  are 
plainly  correlated,  as  is  the  texture  of  the  hair  with  its 
color  in  the  Mandans  of  North  America,  f  The  color  also 
of  the  skin  and  the  odor  emitted  by  it  are  likewise  in  some 
manner  connected.  AVith  the  breeds  of  sheep  the  number 
of  hairs  within  a  given  space  and  the  number  of  the  ex- 
cretory pores  are  related.];  If  we  may  Judge  from  the 
analogy  of  our  domesticated  animals,  many  modifications 
of  structure  in  man  probably  come  under  this  principle 
of  correlated  development. 

We  have  now  seen  that  the  external  characteristic  differ- 
ences between  the  races  of  man  cannot  be  accounted  for  in 
a  satisfactory  manner  by  the  direct  action  of  the  conditions 
of  life,  nor  by  the  effects  of  the  continued  use  of  parts, 
nor  through  the  principle  of  correlation.  We  are  there- 
fore led  to  inquire  whether  slight  individual  differences,  to 
which  man  is  eminently  liable,  may  not  have  been  pre- 
served and  augmented  during  a  long  series  of  generations 
through  natural  selection.     But  here  we  are  at  once  met 

*See  Prof.  ScLaaffliausen,  translat.,  in  "Anthropological  Review," 
Oct.,  1868,  p.  429. 

f  Mr.  Catlin  states  {"  Nortli  American  Indians,"  3d  edit.,  1842,  vol. 
i,  p.  49)  that  in  the  whole  tribe  of  the  Mandans,  about  one  in  ten  or 
twelve  of  the  members,  of  all  ages  and  both  sexes,  have  bright  sil- 
very gray  hair,  which  is  hereditary.  Now  this  hair  is  as  coarse  and 
harsh  as  that  of  a  horse's  mane,  while  the  hair  of  other  colors  is  fine 
and  soft. 

if  On  the  odor  of  the  skin,  Godron,  "  Siir  I'Espece,"  tom  ii,  p.  217. 
On  the  pores  in  the  skin,  Dr.  Wilckens,  *'  Die  Aufgaben  der  Land- 
wirth.     Zootechnik,"  1809,  s.  7. 


226  THE  DESCENT  OF  MAN, 

by  the  objection  that  beneficial  variations  alone  can  be 
thus  preserved;  and  as  far  as  we  are  enabled  to  judge, 
although  always  liable  to  err  on  this  head,  none  of  the  dif- 
ferences between  the  races  of  man  are  of  any  direct  or 
special  service  to  him.  The  intellectual  and  moral  or 
social  faculties  must  of  course  be  excepted  from  this 
remark.  The  great  variability  of  all  the  external  differ- 
ences between  the  races  of  man,  likewise  indicates  that 
they  cannot  be  of  much  importance;  for  if  important,  they 
would  long  ago  have  been  either  fixed  and  preserved  or 
eliminated.  In  this  respect  man  resembles  those  forms, 
called  by  naturalists  protean  or  polymorphic,  which  have 
remained  extremely  variable,  owing,  as  it  seems,  to  such 
variations  being  of  an  indifferent  nature,  and  to  their 
having  thus  escaped  the  action  of  natural  selection. 

We  have  thus  far  been  baffled  in  all  our  attempts  to 
account  for  •  the  differences  between  the  races  of  man  ;  but 
there  remains  one  important  agency,  namely  Sexual  Selec- 
tion, which  appears  to  have  acted  powerfully  on  man,  as 
on  many  other  animals.  I  do  not  intend  to  assert  that 
sectual  selection  will  account  for  all  the  differences  between 
the  races.  An  unexplained  residuum  is  left,  about  which 
we  can  only  say,  in  our  ignorance,  that  as  individuals  are 
continually  born  with,  for  instance,  heads  a  little  rounder 
or  narrower,  and  with  noses  a  little  longer  or  shorter,  such 
slight  differences  might  become  fixed  and  uniform,  if  the 
unknown  agencies  which  induced  them  were  to  act  in  a 
more  constant  manner,  aided  by  long-continued  inter- 
crossing. Such  variations  come  under  the  provisional 
class,  alluded  to  in  our  second  chapter,  which  for  the  want 
of  a  better  term  are  often  called  spontaneous.  Nor  do  I 
pretend  that  the  effects  of  sexual  selection  can  be  indicated 
with  scientific  precision  ;  but  it  can  be  shown  that  it 
would  be  an  inexplicable  fact  if  man  had  not  been  modi- 
fied by  this  agency,  which  appears  to  have  acted  power- 
fully on  innumerable  animals.  It  can  further  be  shown 
that  the  differences  between  the  races  of  man,  as  in  color, 
hairiness,  form  of  features,  etc.,  are  of  a  kind  which  might 
have  been  expected  to  come  under  the  influence  of  sexual 
selection.  But  in  order  to  treat  this  subject  properly,  I 
have  found  it  necessary  to  pass  the  whole  animal  kingdom 
in  review.  I  have  therefore  devoted  to  it  Part  II  of  this 
work,     At  the  qlos^  I  shall  return  to   man,    and,    after 


THE  RACES  OF  MAN.  227 

attempting  to  show  how  far  he  has  been  modified  through 
sexual  selection,  will  give  a  brief  summary  of  the  chapters 
in  Part  I. 

Note  on  the  Resemblances  and  Differences  in  the  Structure 
AND  the  Development  of  the  Brain  in  Man  and  Apes. 
By  Prof.  Huxley,  F.R.S. 

The  controversy  respecting  the  nature  and  the  extent  of  the  differ- 
ences in  the  structure  of  the  brain  in  man  and  the  apes,  which  arose 
some  fifteen  years  ago,  has  not  yet  come  to  an  end,  though  the  sub- 
ject matter  of  the  dispute  is,  at  present,  totally  different  from  what 
it  was  formerly.  It  was  originally  asserted  and  reasserted,  with  sin- 
gular pertinacity,  that  the  brain  of  all  the  apes,  even  the  highest, 
differs  from  that  of  man,  in  the  absence  of  such  conspicuous  struct- 
ures as  the  posterior  lobes  of  the  cerebral  hemispheres,  with  the  pos- 
terior cornu  of  the  lateral  ventricle  and  the  hippocampus  minor,  con- 
tained in  those  lobes,  which  are  so  obvious  in  man. 

But  the  truth  that  the  three  structures  in  question  are  as  well 
developed  in  apes  as  in  human  brains,  or  even  better;  and  that  it  is 
characteristic  of  all  the  Primates  (if  we  exclude  the  Lemurs)  to  have 
these  parts  well  developed,  stands  at  present  on  as  secure  a  basis  as 
any  proposition  in  comparative  anatomy.  Moreover,  it  is  admitted 
by  every  one  of  the  long  series  of  anatomists  who,  of  late  years,  have 
paid  special  attention  to  the  arrangement  of  the  complicated  sulci 
and  gyri  which  ap|>ear  upon  the  surface  of  the  cerebral  hemispheres 
in  man  and  the  higher  apes,  that  they  are  disposed  after  the  very 
same  pattern  in  him  as  in  them.  Every  principal  gyrus  and  sulcus 
of  a  chimpanzee's  brain  is  clearly  represented  in  that  of  a  man,  so 
that  the  terminology  which  applies  to  the  one  answers  for  the  other. 
On  this  point  there  is  no  difference  of  opinion.  Some  years  since. 
Prof.  Bischoff  published  a  memoir*  on  the  cerebral  convolutions  of 
man  and  apes;  and  as  the  purpose  of  my  learned  colleague  was  cer- 
tainly not  to  diminish  the  value  of  the  differences  between  apes  and 
men  in  this  respect,  I  am  glad  to  make  a  citation  from  him. 

•*  That  the  apes,  and  especially  the  orang,  chimpanzee  and  gorilla, 
come  very  close  to  man  in  their  organization,  much  nearer  than  to 
any  other  animal,  is  a  well-known  fact,  disputed  by  nobody.  Look- 
ing at  the  matter  from  the  point  of  view  of  organization  alone,  no 
one  probably  would  ever  have  disputed  the  view  of  Linnaeus,  that 
man  should  be  placed,  merely  as  a  peculiar  species,  at  the  head  of 
the  mammalia  and  of  those  apes.  Both  show,  in  all  their  organs,  so 
close  an  affinity  that  the  most  exact  anatomical  investigation  is  needed 
in  order  to  demonstrate  those  differences  which  really  exist.  So  it  is 
with  the  brains.  The  brains  of  man,  the  orang,  the  chimpanzee,  the 
gorilla,  in  spite  of  all  the  important  differences  which  they  present, 
come  very  close  to  one  another ''  (1.  c,  p.  101). 

There  i-emains.  then,  no  dispute  as  to  the  resemblance  in  funda- 
mental characters,  between  the  ape's  brain  and  man's;  nor  any  as  to 

*"Die  Grosshim-Windungen  des  Menschen;"   *' Abhandlungen  der  K. 
gayerischen  Ak^emie,"  Bd.  x,  186a 


228  THE  DESCENT  OF  MAN. 

the  wonderfully  close  similarity  between  the  chimpanzee,  orang  and 
man,  in  even  the  details  of  the  arrangement  of  the  gyri  and  sulci  of 
the  cerebral  hemispheres.  Nor,  turning  to  the  differences  between 
the  brains  of  the  highest  apes  and  that  of  man,  is  there  any  serious 
question  as  to  the  nature  and  extent  of  these  differences.  It  is  ad- 
mitted that  the  man's  cerebral  hemispheres  are  absohitely  and  rela- 
tively larger  tban  those  of  the  orang  and  chimpanzee;  that  his  frontal 
lobes  are  less  excavated  by  the  upward  protrusion  of  the  roof  of  the 
orbits;  that  his  gyri  and  sulci  are,  as  a  rule,  less  symmetrically  dis- 
posed, and  present  a  greater  number  of  secondary  plications.  And  it 
is  admitted  that,  as  a  rule,  in  man,  the  tempore  occipital  or  "exter- 
nal perpendicular "  fissure,  which  is  usually  so  strongly  marked  a 
feature  of  the  ape's  brain  is  but  faintly  marked.  But  it  is  also  clear, 
that  none  of  these  differences  constitutes  a  sharp  demarcation  between 
the  man's  and  the  ape's  brain.  In  respect  to  the  external  perpendic- 
ular fissure  of  Gratiolet,  in  the  human  brain  for  instance,  Prof.  Turner 
remarks  :  * 

"  In  some  brains  it  appears  simply  as  an  indentation  of  the  margin 
of  the  hemisphere,  but  in  others  it  extends  for  some  distance  more  or 
less  transversely  outward.  I  saw  it  in  the  right  hemisphere  of  a 
female  brain  pass  more  than  two  inches  outward;  and  on  another 
specimen,  also  the  right  hemisphere,  it  proceeded  for  four-tenths  of 
an  inch  outward,  and  then  extended  downward  as  far  as  the  lower 
margin  of  the  outer  surface  of  the  hemisphere.  The  imperfect  defi- 
nition of  this  fissure  in  the  majority  of  human  brains,  as  compared 
with  its  remarkable  distinctness  in  the  brain  of  most  Quadrumana,  is 
owing  to  the  presence  in  the  former  of  certain  superficial,  well- 
marked,  secondary  convolutions  which  bridge  it  over  and  connect  the 
parietal  with  the  occipital  lobe.  The  closer  the  first  of  these  bridg- 
ing gyri  lies  to  the  longitudinal  fissure  the  shorter  is  the  external 
parieto-occipital  fissure  "  (1.  c,  p.  12). 

The  obliteration  of  the  external  perpendicular  fissure  of  Gratiolet, 
therefore,  is  not  a  constant  character  of  the  human  brain.  On  the 
other  hand,  its  full  development  is  not  a  constant  character  of  the 
higher  ape's  brain.  For,  in  the  chimpanzee,  the  more  or  less  exten- 
sive obliteration  of  the  external  perpendicular  sulcus  by  "  bridging 
convolutions,"  on  one  side  or  the  other,  has  been  noted  over  and  over 
again  by  Prof.  Rolleston,  Mr.  Marshall,  M.  Broca  and  Prof.  Turner. 
At  the  conclusion  of  a  special  paper  on  this  subject  the  latter  writes :f 

*'  The  three  specimens  of  the  brain  of  a  chimpanzee  just  described, 
prove  that  the  generalization  which  Gratiolet  has  attempted  to  draw 
of  the  complete  absence  of  the  first  connecting  convolution  and  the 
concealment  of  the  second,  as  essentially  characteristic  features  in  the 
brain  of  this  animal,  is  by  no  means  universally  applicable.  In  only 
one  specimen  did  the  brain,  in  these  particulars,  follow  the  law 
which  Gratiolet  has  expressed.  As  regards  the  presence  of  the 
superior  bridging  convolution,  I  am  inclined  to  think  that  it  has 
existed  in  one  hemisphere,  at  least,  in  a  majority  of  the  brains  of  this 

*  "  Convolutions  of  the  Human  Cerebrum  Topogi-aphically  Considered," 
18(56,  p.  12. 

t  Notes  more  especially  on  the  bridffinf?  convolutions  in  the  brain  of  the 
chimpanzee,  "  Proceedinffs  of  the  Royal  Society  of  Edinburgh,"  1865-66. 


TBE  RACES  OF  MAN.  22^ 

animal  wbicli  have,  up  to  tliis  time,  been  figured  or  described.  Tbe 
superficial  position  of  tbe  second  bridging  convolution  is  evidently 
less  frequent,  and  bas  as  yet,  I  believe,  only  been  seen  in  tbe  brain 
(A)  recorded  in  tbis  communication.  Tbe  asyunnetrical  arrangement 
in  tbe  convolutions  of  tbe  two  bemispberes,  wbicb  previous  observ- 
ers bave  referred  to  in  their  descriptions,  is  also  well  illustrated  in 
these  specimens  "  (pp.  8,  9). 

Even  were  the  presence  of  the  temporo-occipital,  or  external  per- 
pendicular, sulcus,  a  mark  of  distinction  between  tbe  higher  apes 
and  man,  tbe  value  of  such  a  distinctive  character  would  be  ren- 
dered very  doubtful  by  tbe  structure  of  the  brain  in  the  Platyrrbine 
apes.  In  fact,  while  the  temporo-occipital  is  one  of  tbe  most  con- 
stant of  sulci  in  the  Catarrbine,  or  Old  World,  apes,  it  is  never  very 
strongly  developed  in  tbe  New  World  apes;  it  is  absent  in  tbe  smaller 
Platy rrhini ;  rudimentary  in  Pithecia  ;*  and  more  or  less  obliterated 
by  bridging  convolutions  in  Ateles. 

A  character  wbicb  is  thus  variable  within  tbe  limits  of  a  single 
group  can  bave  no  great  taxonomic  value. 

It  is  further  established  that  the  degree  of  asymmetry  of  tbe  con- 
volution of  the  two  sides  in  the  human  brain  is  subject  to  much  indi- 
vidual variation;  and  that,  in  those  individuals  of  the  Bushman 
race  who  have  been  examined,  tbe  gyri  and  sulci  of  the  two  hemis- 
pheres are  considerably  less  complicated  and  more  symmetrical  than 
in  tbe  European  brain,  while,  in  some  individuals  of  the  chimpanzee, 
their  complexity  and  asymmetry  become  notable.  This  is  particu- 
larly the  case  in  the  brain  of  a  young  male  chimpanzee  figured  by  M. 
Broca  ("  L'ordre  des  Primates,"  p.  165,  fig.  11). 

Again,  as  respects  the  question  of  absolute  size,  it  is  established 
that  tbe  difference  between  the  largest  and  the  smallest  healthy 
human  brain  is  greater  than  the  difference  between  tbe  smallest 
healthy  human  brain  and  the  largest  chimpanzee's  or  orang's  brain. 

Moreover,  there  is  one  circumstance  in  which  the  orang's  and  tbe 
chimpanzee's  brains  resemble  man's,  but  in  which  they  differ  from  tbe 
lower  apes,  and  that  is  the  presence  of  two  corpora  candicantia — tbe 
Gynomorpha  having  but  one. 

In  view  of  these  facts  1  do  not  hesitate  in  this  year,  1874,  to 
repeat  and  insist  upon  the  proposition  which  I  enunciated  in  1863:f 

"■  So  far  as  cerebral  structure  goes,  therefore,  it  is  clear  that  man 
differs  less  from  the  chimpanzee  or  the  orang,  than  these  do  even 
from  the  monkeys,  and  that  tbe  difference  between  the  brain  of  the 
chimpanzee  and  of  man  is  almost  insignificant  when  compared  with 
that  between  the  chimpanzee  brain  and  that  of  a  Lemur." 

In  the  })aper  to  wbicb  I  have  referred,  Prof.  Bischoff  does  not 
deny  the  second  part  of  tbis  statement,  but  he  first  makes  the  irrele- 
vant remark  that  it  is  not  wonderful  if  the  brains  of  an  orang  and  a 
Lemur  are  very  different;  and  secondly,  goes  on  to  assert  that,  "  If 
we  successively  compare  tbe  brain  of  a  man  with  that  of  an  orang; 
the  brain  of  tbis  with  that  of  a  chimpanzee;  of  tbis  with  that  of  a 
gorilla,  and  so  on  of  a  Hylohates,  Semnopitliecus,  Gynocephalua,  Ger- 

*  Flower  "On  the  Anatomy  of  Pitliecla  Manachtis,''  "  Proceedings  of  the 
Zoological  Society,"  18(J2. 

t "  Man's  Place  in  Nature,"  p.  102, 


2B0  ^liE  DESGEifT  OF  MA^tT. 

copithecuft,  Macacus,  Gebus,  Callithrix,  Lemur,  Stenops,  Itapate,  \v& 
shall  not  meet  with  a  greater,  or  even  as  great,  a  break  in  the  degree 
of  development  of  the  convolutions,  as  we  find  between  the  brain  of 
a  man  and  that  of  an  orang  or  chimpanzee." 

To  which  I  reply,  firstly,  that  whether  this  assertion  be  true  or 
false,  it  has  nothing  whatever  to  do  with  the  proposition  enunciated 
in  "  Man's  Place  in  Nature,"  which  refers  not  to  the  development  of 
the  convolutions  alone,  but  to  the  structure  of  the  whole  brain.  If 
Prof.  Bischoff  had  taken  the  trouble  to  refer  to  p.  96  of  the  work  he 
criticises,  in  fact,  he  would  have  found  the  following  passage:  "  And 
it  is  a  remarkable  circumstance  that  though,  so  far  as  our  present 
knowledge  extends,  there  is  one  true  structural  break  in  the  series  of 
forms  of  Simian  brains,  this  hiatus  does  not  lie  between  man  and  the 
manlike  apes,  but  between  the  lower  and  the  lowest  Simians,  or  in 
other  words,  between  the  Old  and  New  World  apes  and  monkeys  and 
the  Lemurs.  Every  Lemur  which  has  yet  been  examined,  in  fact, 
has  its  cerebellum  partially  visible  from  above;  and  its  posterior  lobe, 
with  the  contained  posterior  cornu  and  hippocampus  minor,  more  or 
less  rudimentary.  Every  marmoset,  American  monkey.  Old  World 
monkey,  baboon,  or  manlike  ape,  on  the  contrary,  has  its  cerebellum 
entirely  hidden,  posteriorly,  by  the  cerebral  lobes,  and  possesses  a 
large  posterior  cornu  with  a  well-developed  hippocampus  minor." 

This  statement  was  a  strictly  accurate  account  of  what  was  known 
when  it  was  made;  and  it  does  not  appear  to  me  to  be  more  than 
apparently  weakened  by  the  subsequent  discovery  of  the  relatively 
small  development  of  the  posterior  lobes  in  the  Siamang  and  in  the 
Howling  monkey.  Notwithstanding  the  exceptional  brevity  of  the 
posterior  lobes  in  these  two  species,  no  one  will  pretend  that  their 
brains  in  the  slightest  degree  approach  those  of  the  Lemurs.  And 
if,  instead  of  putting  Hapale  out  of  its  natural  place,  as  Prof  Bischoff 
most  unaccountably  does,  we  write  the  series  of  animals  he  has 
chosen  to  mention  as  follows  :  Homo,  Pithecus,  Troglodytes,  Jlylo- 
hates,  Seninopithecus,  Cynocephalus,  Gercopithecus,  Maeacus,  Ge'hus, 
Gallithrix,  Hapale,  Lemur,  Stenops.  I  venture  to  reaffirm  that  the 
groat  break  in  this  series  lies  between  Hapale  and  Jjemur,  and  that 
this  break  is  considerably  greater  than  that  between  any  other  two 
terms  of  that  series.  Prof.  Bischoflf  ignores  the  fact  that  long  before 
he  wrote  (Jratiolet  had  suggested  the  separation  of  the  Lemurs  from 
tlie  other  Primates  on  the  very  ground  of  the  difference  in  their  cere- 
bral characters  ;  and  that  Prof.  Flower  had  made  the  following 
observations  in  the  course  of  his  description  of  the  brain  of  the  Javan 


ioris 


* 


"  And  it  is  especially  remarkable  that,  in  the  development  of  the 
posterior  lobes,  there  is  no  approximation  to  the  Lem  urine,  short - 
hemisphered  brain,  in  those  monkeys  which  are  commonly  supposed 
to  approach  this  family  in  other  respects,  viz.,  the  lower  members  of 
the  Platyrrhine  group." 

So  far  as  the  structure  of  the  adult  brain  is  concerned,  then,  the 
very  considerable  additions  to  our  knowledge,  which  have  been  made 
by  the  researches  of  so  many  investigators  during  the  past  ten  years 
fully  justify  the  statement  which  I  made  in  1863.     But  it  has  been 

*  "  Transactions  of  the  Zoological  Society,"  vol.  v,  1862. 


me  hacms  op  man.  2^i 

said  that,  admitting  the  similarity  between  tlie  adult  brains  of  man 
and  apes,  they  are,  nevertheless,  in  reality,  widely  different,  because 
they  exhibit  fundamental  differences  in  the  mode  of  their  develop- 
ment. No  one  would  be  more  ready  than  I  to  admit  the  force  of  this 
argument,  if  such  fundamental  differences  of  development  really 
exist.  But  I  deny  that  they  do  exist.  On  the  contrary,  there  is  a 
fundamental  agreement  in  the  development  of  the  brain  in  men  and 
apes. 

Gratiolet  originated  the  statement  that  there  is  a  fundamental  dif- 
ference in  the  development  of  the  brains  of  apes  and  that  of  man — 
consisting  in  this;  that  in  the  apes  the  Sulci  which  first  make  their 
appearance  are  situated  on  the  posterior  region  of  the  cerebral  hem- 
ispheres, while  in  the  human  foetus  the  sulci  firp*  become  visible  on 
the  frontal  lobes.* 

This  general  statement  is  based  upon  two  observations,  the  one  of 
a  Gibbon  almost  ready  to  be  born,  in  which  the  posterior  gyri  were 
"well  developed,"  while  those  of  the  frontal  lobes  were  "hardly 
indicated  "f  (1.  c,  p.  39),  and  the  other  of  a  human  foetus  at  the 
22d  or  23d  week  of  uterogestation,  in  which  Gratiolet  notes  that  the 
insula  was  uncovered,  but  that  nevertheless  "des  incisures  sement 
de  lobe  anterieur,  une  scissure  peu  profonde  indique  la  separation  du 
lobe  occipital,  tres-reduit,  d'ailleurs  des  cette  epoque.  Le  reste  de  la 
surface  cerebrale  est  encore  absolumentlisse." 

Three  views  of  this  brain  are  given  in  plate  2,  figs.  1,  2,  3,  of  the 
work  cited,  showing  the  upper,  lateral  and  inferior  views  of  the 
hemispheres,  but  not  the  inner  view.  It  is  worthy  of  note  that  the 
figure  by  no  means  bears  out  Gratiolet's  description,  inasmuch  as  the 
fissure  (antero-temporal)  on  the  posterior  half  of  the  face  of  the  hem- 
isphere is  more  marked  than  any  of  those  vaguely  indicated  in  the 
anterior  half.  If  the  figure  is  correct,  it  in  no  way  justifies  Gratio- 
let's conclusion:  "II  y  a  done  entre  ces'cerveaux  [those  of  a  Calli- 
thrix  and  of  a  Gibbon]  et  celui  du  foetus  humain  une  difference  fonda- 
mental.  Chez  celui-ci,  longtemps  avant  que  les  plis  temporaux 
apparaissent,  les  plis  frontaux  essayent  ^'e^isier" 

Since  Gratiolet's  time,  however,  the  development  of  the  gyri  and 

*  "  Chez  tons  les  singes,  les  plis  posterieurs  se  developpent  les  premiers  ; 
les  plis  anterieurs  se  developpent  plus  tard,  aussi  la  vertebre  occipitale  et  la 
parietale  8«jnt-elles  relativement  tresgrandes  chez  le  fcetus.  L'Hurame  pres- 
ente  une  exception  reniarquable  quant  a  I'epoque  de  Tapparition  des  plis 
frontaux,  qui  sont  les  premiers  indiques  ;  mais  le  developpement  general  du 
lobe  frontal,  envisage  seulement  par  rapport  a  son  volume,  suit  les  memes  lois 
que  dans  les  singes  ;''  Gratiolet,  "  Memoire  sur  les  plis  cerebraux  de  I'Homme 
et  des  Primates,"  p.  39,  Tab.  iv,  fig.  3. 

+  Gratiolet's  words  are  (1.  c.,  p.  39):  "Dans  le  foetus  dont  11  a'agit  les  plis 
cerebraux  posterieurs  sont  bien  developpes,  tandis  que  les  plis  du  lobe  frontal 
sont  a  peine  indiques."  The  figure,  ht)wever  (PI.  iv,  fig.  3},  shows  the  fissure 
of  Rolando,  and  one  of  the  frontal  sulci,  plainly  enough.  Nevertheless,  M. 
Alix,  in  his  "  Notice  sur  les  travaux  anthropologiques  de  Gratiolet  "  (Mem.  de 
la  Societe  d' Anthropologic  de  Paris."  1868,  p.  3-2),  writes  thus:  *'  Gratiolet  a 
eu  entre  les  mains  le  cerveau  d'un  foetus  de  Gibbon,  singe  eminemment  supe- 
rieur,  et  tellemeut  rapproche  de  Torang,  que  des  naturalistes  tres-competents 
I'ont  range  parmi  les  anthropoides.  M.  Huxley,  par  exemple,  n'hesite  pas  sur 
ce  point.  En  bien,  c'est  sur  le  cerveau  d'un  foetus  de  Gibbon  que  Gratiolet  a 
vu  "  les  circonvolvtioit^  du  lobe  temporosphettoidal  d(ja  dereloppees  wrsqu'll  n''exist- 
ent  pas  encore  de  pli>t  xur  le  lobe  frotit(d.  II  etait  done  bien  autorise  a  dire  que, 
chez  I'Homme  les  circonvolutions  apparaissent  d'a  en  w,  tandis  que  chez  les 
singes  elles  se  developpent  d'zf?  en  a." 


23S  THE  DESCENT  OF  MAN. 

sulci  of  the  brain  has  been  made  the  subject  of  renewed  investigation 
by  Schmidt,  Bischoff,  Pansch,*  and  more  particularly  by  Ecker,+ 
whose  work  is  not  only  the  latest,  but  by  far  the  most  complete 
memoir  on  the  subject. 

The  final  results  of  their  inquiries  may  be  summed  up  as  follows: 

1.  In  the  human  foetus,  the  sylvian  fissure  is  formeci  in  the  course 
of  the  third  month  of  uterogestation.  In  this,  and  in  the  fourth 
month,  the  cerebral  hemispheres  are  smooth  and  rounded  (with  the 
exception  of  the  sylvian  depression),  and  they  project  backward  far 
beyond  the  cerebellum. 

2.  The  sulci,  properly  so  called,  begin  to  appear  in  the  interval 
between  the  end  of  the  fourth  and  the  beginning  of  the  sixth  month 
of  foetal  life,  but  Ecker  is  careful  to  point  out  that,  not  only  the 
time,  but  the  order,  of  their  appearance  is  subject  to  considerable 
individual  variation.  In  no  case,  however,  are  either  the  frontal  or 
the  temporal  sulci  the  earliest. 

The  first  which  appears,  in  fact,  lies  on  the  inner  face  of  the  hem- 
isphere (whence  doubtless  Gratiolet,  who  does  not  seem  to  have 
examined  that  face  in  his  foetus,  overlooked  it),  and  is  either  the 
internal  perpendicular  (occipito- parietal),  or  the  calcarine  sulcus, 
these  two  being  close  together  and  eventually  running  into  one 
another.     As  a  rule  the  occipito-parietal  is  the  earlier  of  the  two. 

3.  At  the  latter  part  of  this  period,  another  sulcus,  the  "  posterio- 
parietal,"  or  "  Fissure  of  Rolando,"  is  developed,  and  it  is  followed, 
in  the  course  of  the  sixth  month  by  the  other  principal  sulci  of  the 
frontal,  parietal,  temporal  and  occipital  lobes.  There  is,  however, 
no  clear  evidence  that  one  of  these  constantly  appears  laefore  the 
other;  and  it  is  remarkable  that,  in  the  brain  at  the  period  described 
and  figured  by  Ecker  (1.  c,  p.  212-213,  Taf.  II,  figs.  1,  2,  3,  4),  the 
antero-temporal  sulcus  {scissure parallele)  so  characteristic  of  the  ape's 
brain,  is  as  well  if  not  better  developed  than  the  fissure  of  Rolando, 
and  is  much  more  marked  than  the  proi)er  frontal  sulci. 

Taking  the  facts  as  they  now  stand,  it  appears  to  me  that  the 
order  .of  the  appearance  of  the  sulci  and  gyri  in  the  foetal  human 
brain  is  in  perfect  harmony  with  the  general  doctrine  of  evolution, 
and  with  the  view  that  man  has  been  evolved  from  some  ape-like 
form;  though  there  can  be  no  doubt  that  that  form  was,  in  many 
respects,  different  from  any  member  of  the  Primates  now  living. 

Von  Baer  taught  us,  half  a  century  ago,  that,  in  the  course  of 
their  development,  allied  animals  put  on  at  first,  the  characters  of 
the  greater  groups  to  which  they  belong,  and,  by  degrees,  assume 
those  which  restrict  them  within  the  limits  of  their  family,  genius, 
and  species;  and  he  proved,  at  the  same  time,  that  no  developmental 
stage  of  a  higher  animal  is  precisely  similar  to  the  adult  condition  of 
any  lower  animal.  It  is  quite  correct  to  say  that  a  frog  passes  through 
the  condition  of  a  fish,  inasmuch  as  at  one  x^eriod  of  its  life  the  tad- 
pole has  all  the  characters  of  a  fish,  and  if  it  went  no  further  would 

♦"Ueber  die  typische  Anordiiunj;  derFurchen  und  Windunfren  auf  den 
Grossbim-IIeniispharen  des  Menschen  und  der  Affen."  "  Archiv.  fur  Anthro- 
pologie,"  iii,  18(58. 

t "  Zur  EiitwickolunffS  fleschichte  der  Furchen  und  Wiiuhinge  i  der  Gross- 
hirn-llemispharen  im  Foetus  des  Menschen."  "  Archiv.  fur  Antliropologie," 
iii,  1868. 


THE  RACES  OF  MAN.  233 

have  to  be  grouped  among  fishes.  But  it  is  equally  true  that  a  tad- 
pole is  very  different  from  any  known  fish. 

In  like  manner,  the  brain  of  a  human  fcetus,  at  the  fifth  month, 
may  correctly  be  said  to  be,  not  only  the  brain  of  an  ape,  but  that  of 
an  Arctopithecine  or  marmoset-like  ape;  for  its  hemispheres,  with 
their  great  posterior  lobster,  and  with  no  sulci  but  the  sylvian  and 
the  calcarine,  present  the  characteristics  found  only  in  the  group  of 
the  Arctopithecine  Pnmates  But  it  is  equally  true,  as  Gratiolet 
remarks,  that  in  its  widely  open  sylvian  fissure  it  differs  from  the 
brain  of  any  actual  marmoset.  No  doubt  it  would  be  much  more 
similar  to  the  brain  of  an  advanced  foetus  of  a  marmoset.  But  we 
know  nothing  whatever  of  the  development  of  the  brain  in  the  mar- 
mosets. In  the  Platyrrhini  proper,  the  only  observation  with  which 
I  am  acquainted  is  due  to  Pansch,  who  found  in  the  brain  of  a  fcetal 
Cebtis  Apella,  in  addition  to  the  sylvian  fissure  and  the  deep  calcarine 
fissure,  only  a  very  shallow  antero-temporal  fissure  {scissure  parallele 
of  Gratiolet). 

Now  this  fact,  taken  together  with  the  circumstance  that  the 
antero-temporal  sulcus  is  present  in  such  Platyrrhini  as  the  Saimiri, 
which  present  mere  traces  of  sulci  on  the  anterior  half  of  the  exterior 
of  the  cerebral  hemispheres,  or  none  at  all,  undoubtedly,  so  far  as  it 
goes,  affords  fair  evidence  in  favor  of  Gratiolet's  hypothesis,  that  the 
posterior  sulci  appear  before  the  anterior,  in  the  brains  of  the 
Platyrrhini.  But  it  by  no  means  follows  that  the  rule  which  may 
hold  good  for  the  Platyrrhini  extends  to  the  Catarrhini.  We  have 
no  information  whatever  respecting  the  development  of  the  brain  in 
the  Cynomorpha;  and  as  regards  the  Anthroporaarpha,  nothing  but 
the  account  of  the  brain  of  the  Gibbon,  near  birth,  already  referred 
to.  At  the  present  moment  there  is  not  a  shadow  of  evidence  to  show 
that  the  sulci  of  a  chimpanzee's  or  orang's  brain  do  not  appear  in  the 
same  order  as  a  man's. 

Gratiolet  opens  his  preface  with  the  aphorism  :  "II  est  dangereux 
dans  les  sciences  de  conclure  trop  vite."  I  fear  he  must  have  for- 
gotten this  sound  maxim  by  the  time  he  had  reached  the  discussion 
of  the  differences  between  men  and  apes  in  the  body  of  his  work.  No 
doubt  the  excellent  author  of  one  of  the  most  remarkable  contribu- 
tions to  the  just  understanding  of  the  mammalian  brain  which  has 
ever  been  made,  would  have  been  the  first  to  admit  the  insufficiency 
of  his  data  had  he  lived  to  profit  by  the  advance  of  inquiry.  The 
misfortune  is  that  his  conclusions  have  been  employed  by  persons 
incompetent  to  appreciate  their  foundation  as  arguments  in  favor  of 
obscurantism.* 

But  it  is  important  to  remark  that,  whether  Gratiolet  was  right  or 
wrong  in  his  hypothesis  respecting  the  relative  order  of  api>earance 
of  the  temporal  and  frontal  sulci,  the  fact  remains,  that  before  either 
temporal  or  frontal  sulci  appear,  the  foetal  brain  of  man  presents 
characters  which  are  found  only  in  the  lowest  group  of  the  PHmates 
(leaving  out  the  Lemurs);  and  that  this  is  exactly  what  we  should 
expect  to  be  the  ca.se  if  man  ha.s  resulted  from  the  gradual  modifica- 
tion of  the  same  form  as  that  from  which  the  other  Primates  have 
sprung. 

*  For  example,  M.  I'Abbe  Lecomte  in  his  terrible  pamphlet,  "  Le  Darwin- 
ismo  et  I'origine  de  rHomme,"  1873. 


234  THE  DESCENT  OF  MAM, 


PART  11. 

SEXUAL  SELECTION. 


CHAPTER  VIII. 

PRIiq^CIPLES   OF   SEXUAL   SELECTION. 

Secondary  sexual  characters — Sexual  selection — Manner  of  action — 
Excess  of  males — Polygamy — The  male  alone  generally  modified 
through  sexual  selection — Eagerness  of  the  male — Variability  of 
the  male — Choice  exerted  by  the  female — Sexual  compared  with 
natural  selection — Inheritance,  at  corresponding  periods  of  life, 
at  corresponding  seasons  of  the  year,  and  as  limited  by  sex — 
Relations  between  the  several  forms  of  inheritance — Causes  why 
one  sex  and  the  young  are  not  modified  through  sexual  selection 
— Supplement  on  the  proportional  numbers  of  the  two  sexes 
throughout  the  animal  kingdom — The  proportion  of  the  sexes  in 
relation  to  natural  selection. 

With  animals  which  have  their  sexes  separated,  the 
males  necessarily  differ  from  the  females  in  their  organs  of 
reproduction;  and  these  are  the  primary  sexual  characters. 
But  the  sexes  often  differ  in  what  Hunter  has  called  secondary 
sexual  characters,  which  are  not  directly  connected  with 
the  act  of  reproduction;  for  instance,  the  male  possesses 
certain  organs  of  sense  or  lr>PAr>-»r>finn,  nf  -^yliinh  fl^p  f^pmir^ 
is  quite  "destitute,  or  has  them  mor^  1v'g-hly-dftvp|oped.  in 
order  that  lie  m a^ readily ^^ad^^-reack-ker-f-xjj-  again  the 
male  "Has  special  organs  of  prehension  for  holding  her 
securely.  These  latter  organs,  of  infinitely  diversified 
kinds,  graduate  into  those  which  are  commonly  ranked  as 
primary,  and  in  some  cases  can  hardly  be  distinguished 
from  them;  we  see  instances  of  this  in  the  complex  append- 
ages at  tlie  apex  of  tlie  abdomen  in  male  insects.  Unless 
indeed  we  confine  the  term  *'  primary  '^  to  the  reproductive 


SEXUAL  SELECTION.  235 

glands,  it  is  scarcely  possible  to  decide  which  ought  to  be 
called  primary  and  which  secondary. 

The  female  often  differs  from  the  male  in  having  organs 
for  the  nourishment  or  protection  of  her  young,  such  as  the 
mammary  glands  of  mammals  and  the  abdominal  sacks  of 
the  marsupials.  In  some  few  cases  also  the  male  possesses 
similar  organs,  which  are  wanting  in  the  female,  such  as 
receptacles  for  the  ova  in  certain  male  fishes,  and  those 
temporarily  developed  in  certain  male  frogs.  The  females 
of  most  bees  are  provided  with  a  special  apparatus  for  col- 
lecting and  carrying  pollen,  and  their  ovipositor  is  modified 
into  a  sting  for  the  defense  of  the  larvae  and  the  community. 
Many  similar  cases  could  be  given,  but  they  do  not  here 
concern  us.  There  are,  however,  other  sexual  differences 
quite  unconnected  with  the  primary  reproductive  organs, 
and  it  is  with  these  that  we  are  more  especially  concerned, 
such  as  the  greater  size,  strength  and  pugnacity  of  the  male, 
his  weapons  of  offense  or  means  of  defense  against  rivals, 
his  gaudy  coloring  aud  various  ornaments,  his  power  of  song 
and  other  such  characters. 

Besides  the  primary  and  secondary  sexual  differences, 
such  as  the  foregoing,  the  males  and  females  of  some 
animals  differ  in  structures  related  to  different  habits 
01  life,  and  not  at  all,  or  only  indirectly,  to  the  repro- 
ductive functions.  Thus  the  females  of  certain  flies/ 
(Culicidae  and  Tabanidae)  are  blood-suckers,  while  the* 
males,  living  on  flowers,  have  mouths  destitute  of  mandii 
bles.*  The  males  of  certain  moths  and  of  some  crustaceans 
(e.  g.  Tanais)  have  imperfect,  closed  mouths,  and  cannot 
feed.  The  complemental  males  of  certain  Cirripedes  live 
like  epiphytic  plants  either  on  the  female  or  the  hermaph- 
rodite form,  and  are  destitute  of  a  mouth  and  of  prehensile 
limbs.  In  these  cases  it  is  the  male  which  has  been  modi- 
fied and  has  lost  certain  important  organs  which  the 
females  possess.  In  other  cases  it  is  the  female  which  has 
lost  such  parts;  for  instance,  the  female  glow-worm  is  des 
titute  of  wings,  as  also  are  many  female  moths,  some  of 
which  never  leave  their  cocoons.  Many  female  parasitic 
crustaceans  have  lost  their  natatory  legs.     In  some  weevil- 

*  West  wood,  "Modern  Class  of  Insects,"  vol.  ii,  1840,  p.  541. 
For  the  statement  about  Tanais,  mentioned  below,  I  am  indebted  to 
Fritz  Miiller. 


^JJ6  THE  DESCENT  OF  MAN. 

beetles  (Curculioniclae)  there  is  a  great  difference  between 
the  male  and  the  female  in  the  length  of  the  rostrum  or 
snout;  *  but  the  meaning  of  this  and  of  many  analogous 
differences  is  not  at  all  understood.  Differences  of  structure 
between  the  two  sexes  in  relation  to  different  habits  of  life 
are  generally  confined  to  the  lower  animals;  but  with  some 
few  birds  the  beak  of  the  male  differs  from  that  of  the 
female.  In  the  Huia  of  New  Zealand  the  difference  is 
wonderfully  great,  and  we  hear  from  Dr.  Buller  \  that  the 
male  uses  his  strong  beak  in  chiseling  the  larvae  of  insects 
out  of  decayed  wood,  while  the  female  probes  the  softer 
parts  with  her  far  longer,  much  curved  and  pliant  beak; 
and  thus  they  mutually  aid  each  other.  In  most  cases 
differences  of  structure  between  the  sexes  are  more  or  less 
directly  connected  with  the  propagation  of  the  species;  thus 
a  female,  which  has  to  nourish  a  multitude  of  ova,  requires 
more  food  than  the  male,  and  consequently  requires  special 
means  for  procuring  it.  A  male  animal,  which  lives  for  a 
very  short  time,  might  lose  its  organs  for  procuring  food 
through  disuse,  without  detriment;  but  he  would  retain  his 
locomotive  organs  in  a  perfect  state,  so  that  he  might  reach 
the  female.  The  female,  on  the  other  hand,  might  safely 
lose  her  organs  for  flying,  swimming,  or  walking,  if  she 
gradually  acquired  habits  which  rendered  such  powers 
useless. 

We  are,  however,  here  concerned  only  with  sexual  selec- 
tion. This  depends  on  the  advantage  which  certain  indi- 
viduals have  over  others  of  the  same  sex  and  species  solely 
in  respect  of  reproduction.  When,  as  in  the  cases  above 
mentioned,  the  two  sexes  differ  in  structure  in  relation  to 
different  habits  of  life,  they  have  no  doubt  been  modified 
through  natural  selection,  and  by  inheritance  limited  to 
one  and  the  same  sex.  So  again  the  primary  sexual 
organs,  and  those  for  nourishing  or  protecting  the  young, 
come  under  the  same  influence;  for  those  individuals  which 
generated  or  nourished  their  offspring  best,  would  leave, 
cceteris  paribus,  the  greatest  number  to  inherit  their 
superiority;  while  those  which  generated  ornourislied  their 
offspring  badly  would  leave  but  few  to  inherit  their  weaker 
powers.     As  the  male  hae  to  find  the  female  he  requires 

*Kirby  and  Speuce,  "Introduction  to  Entomology,"  vol.  iii,  1826, 
p.  309. 

\  "  Birds  of  New  Zealand,"  1872,  p.  66. 


SEXUAL  SELECTION.  237 

oralis  of  sense  and  locomotion,  bnt  if  these  organs  are 
neces8Hry  for  the  other  jmrposes  of  life,  as  is  generally  the 
case,  they  will  have  been  tleveloped  through  natural  selec- 
tion. When  the  male  ha:<  found  the  female  he  sometimes 
absolutely  requires  prehensile  organs  to  hold  her;  thus  Dr. 
Wallace  informs  me  that  the  males  of  certain  moths  cannot 
unite  with  the  females  if  their  tai*si  or  feet  are  broken. 
The  males  of  many  oceanic  crustaceans,  when  adult,  have 
their  legs  and  antennie  modified  in  an  extraordinary 
manner  for  the  prehension. of  the  female;  hence  we  may 
suspect  that  it  is  because  these  animals  are  washed  about 
by  the  waves  of  the  open  sea  that  they  require  these  organs 
in  order  to  propagate  their  kind,  and,  if  so,  their  develop- 
ment has  been  the  result  of  ordinary  or  natural  selection. 
Some  animals  extremely  low  in  the  scale  have  been  modified 
for  this  same  purpose;  thus  the  males  of  certain  parasitic 
worms,  when  fully  grown,  have  the  lower  surface  of  the 
terminal  part  of  their  bodies  roughened  like  a  rasp,  and 
with  this  they  coil  round  and  permanently  hold  the 
females.* 

When  the  two  sexes  follow  exactly  the  same  habits  of 
life,  and  the  male  has  the  censory  or  locomotive  organs 
more  highly  developed  than  those  of  the  female,  it  may  be 
that  the  perfection  of  these  is  indispensable  to  the  male  for 
finding  the  female;  but  in  the  vast  majority  of  cases,  they 
serve  only  to  give  one  male  an  advantage  over  another,  for 
with  sufficient  time  the  less  well-endowed  males  would  suc- 
ceed in  pairing  with  the  females;  and  judging  from  the 
structure  of  the  female,  they  would  be  in  all  other  respjects 
equally  well  adapted  for  their  ordinary  habits  of  life.  Since 
in  such  cases  the  males  have  acquired  their  present  struct- 
ure not  from  being  better  fitted  to  survive  in  the  struggle 

*M.  Perrier  advances  this  case  ("Revue  Scieutifique,"  Feb.  1, 
1873,  p.  865)  as  one  fatal  to  the  belief  in  sexual  selection,  inasmuch 
as  he  supposes  that  I  attribute  all  the  diflferences  between  the  sexes 
to  sexual  selection.  This  distinguished  naturalist,  therefore,  like  so 
many  other  Frenchmen,  has  not  taken  the  trouble  to  understand  even 
the  first  principles  of  sexual  selection.  An  English  naturalist  insists 
that  the  claspers  of  certain  male  animals  could  not  have  been  devel- 
oped through  the  choice  of  the  female  !  Had  I  not  met  with  this 
remark  I  should  not  have  thought  it  possible  for  any  one  to  have 
read  this  chapter  and  to  have  imagined  that  I  maintain  that  the 
choice  of  the  female  had  anything  to  do  with  the  development  of  the 
prehensile  organs  in  the  male. 


238  THE  DESCENT  OF  MAN. 

for  existence,  but  from  having  gained  an  advantage  over 
other  males,  and  from  liaving  transmitted  this  advantage  to 
their  male  offspring  alone,  sexual  selection  must  here  have 
come  into  action.  It  was  the  importance  of  this  distinction 
which  led  me  to  designate  this  form  of  selection  as  sexual 
selection.  ^1^0  again,  if  the  chief  service  rendered  to  the 
male  by  his  prehensile  organs  is  to  prevent  the  escajie  of  the 
female  before  the  arrival  of  other  males,  or  when  assaulted 
by  them  these  organs  will  have  been  perfected  through 
sexual  selection,  that  is,  by  the  advantage  acquired  by  certain 
individuals  over  their  rivals.  J  But  in  most  cases  of  this 
kind  it  is  impossible  to  distinguish  between  the  effects  of 
natural  and  sexual  selection.  Whole  chapters  could  be 
filled  with  details  on  the  differences  between  the  sexes 
in  their  sensory,  locomotive  and  prehensile  organs.  As, 
however,  these  structures  are  not  more  interesting  than 
others  adapted  for  the  ordinary  purposes  of  life  I  shall  pass 
them  over  almost  entirely,  giving  only  a  few  instances  under 
each  class. 

CThere  are  many  other  structures  and  instincts  which 
must  have  been  developed  through  sexual  selection,  such 
as  the  weapons  of  offense  and  the  means  of  defense  of  the 
males  for  fighting  with  and  driving  away  their  rivals — their 
courage  and  pugnacity — their  various  ornaments — their 
contrivances  for  producing  vocal  or  instrumental  music — 
and  their  glands  for  omitting  odors,  most  of  these  latter 
structures  serving  only  to  allure  or  excite  the  female.  It 
is  clear  that  these  characters  are  the  result  of  sexual  and 
not  of  ordinary  selection,  since  unarmed,  unornamented,  or 
unattractive  males  would  succeed  equally  well  in  the  battle 
for  life  and  in  leaving  a  numerous  progeny,  but  for  the 
presence  of  better  endowed  males.  We  may  infer  that  this 
would  be  the  case,  because  the  females,  which  are  unarmed 
and  unornamented,  are  able  to  survive  and  procreate  their 
kind.  Secondary  sexual  characters  of  the  kind  just 
referred  to,  will  be  fully  discussed  in  the  following  chap- 
ters, as  being  in  many  respects  interesting,  but  especially 
as  depending  on  the  will,  choice,  and  rivalry  of  the  indi- 
viduals of  either  sex.  When  we  behold  two  males  fighting 
for  the  possession  of  the  female,  or  several  male  birds  dis- 
playing their  gorgeous  plumage  and  performing  strange 
antics  before  an  assembled  body  of  females,  we  cannot  doubt 
that,  though  led  by  instinct,  they  know  what  they  are 


SEXUAL  SELECTION.  239 

about,  and  consciously  exert  their  mental  and  bodily 
powers.  T 

Just  as  man  can  improve  the  breed  of  his  game-cocks  by 
the  selection  of  those  birds  which  are  victorious  in  the 
cock-pit,  so  it  appears  that  the  strongest  and  most  vigorous 
males,  or  those  pronded  with  the  best  weapons,  have  pre- 
vailed under  nature,  and  have  led  to  the  improvement  of 
the  natural  breed  or  species.  A  slight  degree  of  variability 
leading  to  some  advantage,  however  slight,  in  reiterated 
deadly  contests  would  suffice  for  the  work  of  sexual  selec- 
tion; and  it  is  certain  that  secondary  sexual  characters  are 
eminently  variable.  Just  as  man  can  give  beauty,  accord- 
ing to  his  standard  of  tase,  to  his  male  poultry,  or  more 
strictly  can  modify  the  beauty  originally  acquired  by  the 
parent  species,  can  give  to  the  Sebright  bantam  a  new  and 
elegant  plumage,  an  erect  and  peculiar  carriage — so  it 
appears  that  female  birds  in  a  state  of  nature  have  by  a 
long  selection  of  the  more  attractive  males  added  to 
their  beauty  or  other  attractive  qualities.  No  doubt 
this  implies  powers  of  discrimination  and  taste  on  the  part 
of  the  female,  which  will  at  first  appear  extremely  improb- 
able; but  by  the  facts  to  be  adduced  hereafter,  I  hope  to 
be  able  to  show  that  the  females  actually  have  these 
powers.  When,  however,  it  is  said  that  the  lower  animals 
have  a  sense  of  beauty,  it  must  not  be  supposed  that  such 
sense  is  comparable  with  that  of  a  cultivated  man,  with  his 
multiform  and  complex  associated  ideas.  A  more  just 
comparison  would  be  between  the  taste  for  the  beautiful  in 
animals,  and  that  in  the  lowest  savages,  who  admire  and 
deck  themselves  with  any  brilliant,  glittering,  or  curious 
object. 

From  our  ignorance  on  several  points,  the  precise  manner 
in  which  sexual  selection  acts  is  somewhat  uncertain. 
Nevertheless,  if  those  naturalists  who  already  believe  in  the 
mutability  of  species,  will  read  the  following  chapters,  they 
will,  I  think,  agree  with  me  that  sectual  selection  has 
played  an  important  part  in  the  history  of  the  organic 
world.  ^It  is  certain  that  among  almost  all  animals  there  is 
a  struggle  between  the  males  for  the  possession  of  the 
female.  This  fact  is  so  notorious  that  it  would  be  super- 
fluous to  give  instances.  Hence  the  females  have  the  oppor- 
tunity of  selecting  one  out  of  several  males,  on  the  suppo- 
sition that  their  mental  capacity  suffices  for  the  exertion  of 


240  THE  DESCENT  OF  MAN. 

a  choice.  In  many  cases  special  circumstances  tend  to 
make  the  struggle  between  the  males  particularly  severe. 
Thus  the  males  of  our  migratory  birds  generally  arrive  at 
their  places  of  breeding  before  the  females,  so  that  many 
males  are  ready  to  contend  for  each  female.'HI  am  informed 
by  Mr.  Jenner  Weir,  that  the  bird-catcherSlissert  that  this 
is  invariably  the  case  with  the  nightingale  and  blackcap, 
and  with  respect  to  the  latter  he  can  himself  confirm  the 
statement. 

Mr.  Swaysland,  of  Brighton,  has  been  in  the  habit  during 
the  last  forty  years  of  catching  our  migratory  birds  on 
their  first  arrival,  and  he  has  never  known  the  females  of 
any  species  to  arrive  before  their  males.  During  one 
spring  he  shot  thirty-nine  males  of  Eay^s  wagtail  {Budytes 
Rail)  before  lie  saw  a  single  female.  Mr.  Gould  has  ascer- 
tained by  the  dissection  of  those  snipes  which  arrive  the 
first  in  this  country  that  the  males  come  before  the  females. 
And  the  like  holds  good  with  most  of  the  migratory  birds 
of  the  United  States.*  The  majority  of  the  male  salmon 
in  our  rivers  on  coming  up  from  the  sea  are  ready  to  breed 
before  the  females.  So  it  appears  to  be  with  frogs  and 
toads.  CPln'oughout  the  great  class  of  insects  the  males 
almost  always  are  the  first  to  emerge  from  the  pupal  state, 
so  that  they  generally  abound  for  a  time  before  any  females 
can  be  seen.f  The  cause  of  this  difference  between  the 
males  and  females  in  their  periods  of  arrival  and  maturity 
is  sufficiently  obvious.  Those  males  which  annually  first 
migrated  into  any  country,  or  which  in  the  spring  were 
first  ready  to  breed,  or  the  most  eager,  would  leave  the 
largest  number  of  offspring;  and  these  would  tend  to  in- 
herit similar  instincts  and  constitutionsTj  It  must  be  borne 
in  mind  that  it  would  have  been  impossible  to  change  very 
materially  the  time  of  sexual  maturity  in  the  females  with- 
out at  the  same  time  interferiing  with  the  period  of  the 

*J.  A.  Allen  on  the  "Mammals  and  Winter  Birds  of  Florida," 
Bull.  Comp.  Zoology,  Harvard  College,  p.  268. 

f  Even  witli  tliose  plants  in  wliicli  the  sexes  are  separate,  the  male 
flowers  are  generally  mature  before  the  female.  As  first  shown  by 
C.  K.  Sprengel,  many  hermaphrodite  plants  are  dichogamous;  that 
is,  their  male  and  female  organs  are  not  ready  at  the  same  time,  so 
that  they  cannot  be  self- fertilized.  Now  in  such  flowers  the  pollen 
is  in  general  matured  before  the  stigma,  though  there  are  exceptional 
Cftses  io  which  the  female  organs  are  beforehand. 


SEXUAL  SELECTION.  241 

production  of  the  young — a  period  wliich  must  be  deter- 
mined by  the  seasons  of  the  year.  On  the  whole,  there 
can  be  no  doubt  that  mth  almost  all  animals  in  which  the 
sexes  are  separate  there  is  a  constantly  recurrent  struggle 
between  the  males  for  the  possession  of  the  females. 

Our  difficulty  in  regard  to  sexual  selection  lies  in  under- 
standing how  it  is  that  the  males  which  conquer  other 
males,  or  those  which  prove  the  most  attrative  to  the 
females,  leave  a  greater  number  of  offspring  to  inherit  their 
superiority  than  their  beaten  and  less  attractive  rivals. 
Unless  this  result  does  follow  the  characters  which  give  to 
certain  males  an  advantage  over  others  could  not  be  per- 
fected and  augmented  through  sexual  selection.  When 
the  sexes  exist  in  exactly  equal  numbers  the  worst  endowed 
males  will  (except  where  polygamy  prevails)  ultimately 
find  females  and  leave  as  many  offspring  as  well  fitted  for 
their  general  habits  of  life  as  the  best-endowed  males. 
From  various  facts  and  considerations  I  formerly  inferred 
that  with  most  animals,  in  which  secondary  sexual  charac- 
ters are  well  developed,  the  males  considerably  exceeded 
the  females  in  number;  but  this  is  not  by  any  means 
always  true.  If  the  males  were  to  the  females  as  two  to 
one,  or  three  to  two,  or  even  in  a  somewhat  lower  ratio  the 
whole  affair  would  be  simple;  for  the  better  armed  or  more 
attractive  males  would  leave  the  largest  number  of  offspring. 
But  after  investigating  as  far  as  possible  the  numerical 
proportion  of  the  sexes  I  do  not  believe  that  any  great  in- 
equality in  number  commonly  exists.  In  most  cases  sexual 
selection  appears  to  have  been  effective  in  the  following 
manner: 

CLet  us  take  any  species,  a  bird  for  instance,  and  divide 
the  females  inhabiting  a  district  into  two  equal  bodies,  the 
one  consisting  of  the  more  vigorous  and  better-nourished 
individuals,  and  the  other  of  the  less  vigorous  and  healthy. 
The  former,  there  can  be  little  doubt,  would  be  ready  to 
breed  in  the  spring  before  the  others ;  and  this  is  the 
opinion  of  Mr.  Jenner  Weir,  who  has  carefully  attended  to 
the  habits  of  birds  during  many  years.  There  can  also  be 
no  doubt  that  the  most  vigorous,  best-nourished  and  earliest 
breeders  would  on  an  average  succeed  in  rearing  the 
largest  number  of  fine  offspring.*     The  males,  as  we  have 

*  Here  is  excellent  evidence  on  the  character  of  the  offspring  from 
an  experienced  ornithologist.     Mr.  J.  A.  Allen,  in  speaking  ("  Mam- 


242  THE  DESCENT  OF  MAN. 

seen,  are  generally  ready  to  breed  before  the  females;  the 
stron<^est,  and  with  some  species  the  best  armed  of  the 
males,  drive  away  the  weaker;  and  the  former  woukl  tlicn 
unite  with  the  more  vigorous  and  better-nourislied  females, 
because  they  are  the  first  to  breed. ^  Such  vigorous  pairs 
would  surely  rear  a  larger  number  of  offspring  than  the 
retarded  females,  which  would  be  compelled  to  unite  with 
the  conquered  and  less  powerful  males,  supposing  the  sexes 
to  be  numerically  equal;  and  this  is  all  that  is  wanted  to 
add,  in  the  course  of  successive  generations,  to  the  size, 
strength  and  courage  of  the  males,  or  to  improve  their 
weapons. 

But  in  very  many  cases  the  males  which  conquer  their 
rivals  do  not  obtain  possession  of  the  females,  independently 
of  the  choice  of  the  latter.  The  courtship  of  animals  is 
by  no  means  so  simple  and  short  an  affair  as  might  be 
thought.  QThe  females  are  most  excited  by,  or  prefer  pair- 
ing with,  the  more  ornamented  males,  or  those  which  are 
the  best  songsters,  or  play  the  best  antics;  but  it  is  obviously 
probable  that  they  would  at  the  same  time  prefer  the  more 
vigorous  and  lively  males,  and  this  has  in  some  cases  been 
confirmed  by  the  actual  observation.!  Thus  the  more 
vigorous  females,  which  are  the  first  to  breed,  will  have  the 
choice  of  many  males;  and  though  they  may  not  always 
select  the  strongest  or  best  armed,  they  will  select  those 
which  are  vigorous  and  well  armed,  and  in  other  respects 
the  most  attractive.  Both  sexes,  therefore,  of  such  early 
pairs  would,  as  above  explained,  have  an  advantage  over 
others  in  rearing  offspring ;  and  this  apparently  has 
sufficed  during  a  long  course  of   generations  to  add  not 

mals  and  Winter  Birds  of  E.  Florida,"  p.  329)  of  the  later  broods 
after  the  accidental  destruction  of  the  first,  says  that  these  "  are  found 
to  be  smaller  and  paler-colored  than  those  hatched  earlier  in  the  sea- 
son. In  cases  where  several  broods  are  reared  each  year,  as  a  general 
rule  the  birds  of  the  earlier  broods  seem  in  all  respects  the  most  per 
feet  and  vigorous." 

*  Hermann  Miiller  has  come  to  this  same  conclusion  with  respect 
to  those  female  bees  which  are  the  first  to  emerge  from  the  pupa  each 
year.  See  his  remarkable  essay,  "  Anwendung  den  Darwin'schen 
Lehre  auf  Bienen,"  "  Verb.  d.  V,  Jahrg.,"  xxix,  p.  45. 

f  With  respect  to  poultry,  I  have  received  information,  hereafter  to 
be  given,  to  this  effect.  Even  with  birds,  such  as  pigeons,  which 
pair  for  life,  the  female,  as  I  hear  from  Mr.  Jenuer  Weir,  will  desert 
her  mate  if  he  is  injured  or  grows  weak. 


SEXUAL  SELECTION.  243 

only  to  the  strength  and  fighting  powers   of    the   males, 
but  likewise  to  their  various  ornaments  or  other  attractionsTi 

In  the  converse  and  much  rarer  case  of  the  males  select- 
ing particular  females  it  is  plain  that  those  which  were  the 
most  vigorous  and  had  conquered  others  would  have  the 
freest  choice;  and  it  is  almost  certain  that  they  would  select 
vigorous  as  well  as  attractive  females.  Such  pairs  would 
have  an  advantage  in  rearing  offspring,  more  especially  if 
the  male  had  the  power  to  defend  the  female  during  the 
pairing-season  as  occurs  with  some  of  the  higher  animals,  or 
aided  her  in  providing  for  the  young.  The  same  principles 
would  apply  if  each  sex  preferred  and  selected  certain 
individuals  of  the  opposite  sex;  supposing  that  they  selected 
not  only  the  more  attractive,,  but  likewise  the  more  vigor- 
ous individuals. 

Numerical  Proportion  of  the  Tiuo  Sexes. — I  have  remarked 
that  sexual  selection  would  be  a  simple  affair  if  the  males 
were  considerably  more  numerous  than  the  females.  Hence 
I  was  led  to  investigate,  as  far  as  I  could,  the  proportions 
between  the  two  sexes  of  as  many  animals  as  possible;  but 
the  materials  are  scanty.  I  will  here  give  only  a  brief 
abstract  of  the  results,  retaining  the  details  for  a  supple- 
mentary discussion  so  as  not  to  interfere  with  the  course  of 
my  argument.  Domesticated  animals  alone  afford  the 
means  of  ascertaining  the  proportional  numbers  at  birth; 
but  no  records  have  been  specially  kept  for  this  purpose. 
By  indirect  means,  however,  I  have  collected  a  considerable 
body  of  statistics,  from  which  it  appears  that  with  most 
of  our  domestic  animals  the  sexes  are  nearly  equal  at  birth. 
Thus  25,560  births  of  race-horses  have  been  recorded  during 
twenty-one  years,  ar^d  the  male  births  were  to  the  female 
births  as  99.7  to  100.  In  greyhounds  the  inequality  is 
greater  than  with  any  other  animal,  for  out  of  6,878  births 
during  twelve  years,  the  male  births  were  to  the  female  as 
110.1  to  100.  It  is,  however,  in  some  degree  doubtful 
whether  it  is  safe  to  infer  that  the  proportion  would  be  the 
same  under  natural  conditions  as  under  domestication;  for 
slight  and  unknown  differences  in  the  conditions  affect  the 
proportion  of  the  sexes.  Thus  with  mankind,  the  male 
births  in  England  are  as  104.5,  in  Russia  as  108.9,  and  with 
the  Jews  of  Livonia  as  120  to  100  female  births.  But  I 
shall  recur  to  this  curious  point  of  the  excess  of  male  births 


244  THE  DESCENT  OF  MAN. 

in  the  supplement  to  this  chapter.  At  the  Cape  of  Good 
Hope,  however,  male  chiklren  of  Europeon  extraction  have 
been  born  during  several  yeai's  in  the  proportion  of  between 
90  and  99  to  100  female  children. 

For  our  present  purpose  we  are  concerned  with  the  pro- 
portion of  the  sexes,  not  only  at  birth,  but  also  at  maturity, 
and  this  adds  another  element  of  doubt;  for  it  is  a  well- 
ascertained  fact  that  with  man  the  number  of  males  dying 
before  or  during  birth  and  during  the  first  few  years  of 
infancy  is  considerably  larger  than  that  of  females.  So  it 
almost  certainly  is  with  male  lambs,  and  probably  with 
some  other  animals.  The  males  of  some  species  kill  one 
another  by  fighting;  or  they  drive  one  another  about  until 
they  become  greatly  emaciated.  They  must  also  be  often 
exposed  to  various  dangers  while  wandering  about  in  eager 
search  for  the  females.  In  many  kinds  of  fish  the  males 
are  much  smaller  than  the  females,  and  they  are  believed 
often  to  be  devoured  by  the  latter  or  by  other  fishes.  The 
females  of  some  birds  appear  to  die  earlier  than  the  males; 
they  are  also  liable  to  be  destroyed  on  their  nests  or  while 
in  charge  of  their  young.  With  insects  the  female  larvge 
are  often  larger  than  those  of  the  males,  and  would  conse- 
quently be  more  likely  to  be  devoured.  In  some  cases  the 
mature  females  are  less  active  and  less  rapid  in  their  move- 
ments than  the  males  and  could  not  escape  so  well  from 
danger.  Hence,  with  animals  in  a  state  of  nature  we  must 
rely  on  mere  estimation  in  order  to  judge  of  the  propor- 
tions of  the  sexes  at  maturity;  and  this  is  but  little  trust- 
worthy except  when  the  inequality  is  strongly  marked. 
Nevertheless,  as  far  as  a  judgment  can  be  formed,  we  may 
conclude  from  the  facts  given  in  the  supplement  that  the 
males  of  some  few  mammals,  of  many  birds,  of  some  fish 
and  insects,  are  considerably  more  numerous  than  the 
females. 

The  proportion  between  the  sexes  fluctuates  slightly 
during  successive  years;  thus  with  race-horses,  for  every 
100  mares  born  the  stallions  varied  from  107.1  in  one  year 
to  92.6  in  another  year,  and  with  greyhounds  from  116.3 
to  95.3.  But  had  larger  numbers  been  tabulated  through- 
out an  area  more  extensive  than  England  these  fluctuations 
would  probably  have  disappeared ;  and  such  as  they  are, 
would  hardly  suffice  to  lead  to  effective  sexual  selection  in 
a  state  of  nature.     Nevertheless^  in  the  cases  of  some  few 


Sexual  selection.  245 

wild  animals,  as  shown  in  the  supplement,  the  proportions 
seem  to  fluctuate  either  during  different  seasons  or  in  dif- 
ferent localities  in  a  sufficient  degree  to  lead  to  such  selec- 
tion. For  it  should  be  observed  that  any  advantage  gained 
during  certain  years  or  in  certain  localities  by  those  males 
which  were  able  to  conquer  their  rivals,  or  were  the  most 
attractive  to  the  females,  would  probably  be  transmitted  to 
the  offspring  and  would  not  subsequently  be  eliminated. 
During  the  succeeding  seasons,  when  from  the  equality  of 
the  sexes  every  male  was  able  to  procure  a  female,  the 
stronger  or  more  attractive  males  previously  produced  would 
still  have  at  least  as  good  a  chance  of  leaving  offspring  as 
the  weaker  or  less  attractive. 


Polygamy. — The  practice  of  polygariiy  leads  to  the  same 
results  as  would  follow  from  an  actual  inequality  in  the 
number  of  the  sexes;  for  if  each  male  secures  two  or  more 
females  many  males  cannot  pair;  and  the  latter  assuredly-^ 
will  be  the  weaker  or  less  attractive  individuals.     Many    f 
mammals   and  some  few  birds  are  polygamous,  but  with 
animals  belonging  to  the  lower  classes  I  have  found  no  evi- 
dence of  this  habit.     The  intellectual  powers  of  such  ani-     j 
mals  are,  perhaps,  not  sufficient  to  lead  them  to  collect  and     ! 
guard  a  harem  of  females.  Cjhat  some  relation  exists  be- 
tween polygamy  and  the  development  of  secondary  sexual 
characters  appears  nearly  certain;  and  this  supports  the  "^ 
view  that  a  numerical  preponderance  of  males  would  be 
eminently  favorable   to   the   action   of    sexual    selection. 
Nevertheless  many  animals  which  are  strictly  monogamous, 
especially  birds,  display  strongly  marked  secondary  sexual 
characters;  while  some  few  animals  which  are  polygamous 
do  not  have  such  characters.^ 

We  will  first  briefly  run  through  the  mammals  and 
then  turn  to  birds.  The  .goriUaseems  to  be  polygamous, 
and  the  male  differs  consmeraBly  from  the  female ;  so 
it  is  with  some  baboons,  which  live  in  herds  containing 
twice  as  many  adult  females  as  males.  In  South  America 
the  Mycetes  caraya  presents  well-marked  sexual  differences, 
in  color,  beard,  and  vocal  organs  ;  and  the  male  generally 
lives  with  two  or  three  wives;  the  male  of  the  Cebti.^  capnci- 
nus  differs  somewhat  from  the  female,  and  appears  to  be 


UG  the  DmCENT  Of  MAN. 

polygamous.*  Little  is  known  on  this  head  with  respect  to 
most  other  monkeys,  but  some  species  are  strictly  monoga- 
mous. The  ruminants  are  eminently  polygamous,  and  they 
present  sexual  differences  more  frequently  than  almost  any 
other  group  of  mammals;  this  holds  good,  especially  in 
their  weapons,  but  also  in  other  characters.  Most  deer, 
cattle,  and  sheep  are  polygamous;  as  are  most  antelopes, 
though  some  are  monogamous.  Sir  Andrew  Smith,  in 
speaking  of  the  antelopes  of  S.  Africa,  says  that  in 
herds  of  about  a  dozen  there  was  rarely  more  than  one 
mature  male.  The  Asiatic  AntUope  saiga  appears  to  be  the 
most  inordinate  polygamist  in  the  world;  for  Pallasf  states 
that  the  male  drives  away  all  rivals  and  collects  a  herd  of 
about  a  hundred  females  and  kids  together;  the  female  is 
hornless  and  has  softer  hair,  but  does  not  otherwise  differ 
much  from  the  male.  The  wild  horse  of  the  Falkland 
Islands  and  of  the  Western  States  of  North  America  is 
polygamous,  but,  except  in  his  greater  size  and  the  propor- 
tions of  his  body,  ditt'ers  but  little  from  the  mare.  The 
wild  boar  presents  well-marked  sexual  characters,  in  his 
great  tusks  and  some  other  points.  In  Europe  and  in  India 
he  leads  a  solitary  life,  except  during  the  breeding-season  ; 
but  as  is  believed  by  Sir  W.  Elliot,  who  has  had  many 
opportunities  in  India  of  observing  this  animal,  he  consorts 
at  this  season  with  several  females.  Whether  this  holds 
good  in  Europe  is  doubtful,  but  it  is  supported  by  some 
evidence.  £The  adult  male  Indian  elephant,  like  the  boar, 
passes  much  of  his  time  in  solitude;  but  as  Dr.  Campbell 
states,  when  with  others,  **  it  is  rare  to  find  more  than  one 
male  with  a  whole  herd  of  females ;"  the  larger  males 
expelling  or  killing  the  smaller  and  weaker  ones.  The 
male  differs  from  the  female  in  his  immense  tusks,  greater 
size,  strength  and  endurance;  so  great  is  the  difference  in 
these  respects,  that  the  males  when  caught  are  valued  at 

*0n  the  Gorilla,  Savage  and  Wyman,  **  Boston  Journal  of  Nat. 
Hist.,"  vol.  V,  1845-47,  p.  423.  On  Cynocepbalus,  Brehm,  "  Illust. 
Tbierleben,"  B.  i,  1864,  s.  77.  On  Mycetes,  Rengger,  "  Naturgesch. : 
SJiugethiere  von  Paraguay,"  1830,  ss.  14,  20.  Cebus,  Brebm,  ibid,  s. 
108. 

f  Pallas,  "Spicilegia  Zoolog.,  Fasc,"  xii,  1777,  p.  29.  Sir  Andrew 
Smitb,  "  Illustrations  of  tbe  Zoology  of  S.  Africa,"  1849,  pi.  29,  on 
tbe  Kobus.  Owen,  in  bis  "Anatomy  of  Vertebrates"  (vol.  iii,  1868, 
p.  633)  gives  a  table  sbowing  incidentally  wbicb  species  of  antelopes 
are  gregarious. 


sMtJAL  SELECTION.  241' 

one-fifth  more  than  the  females.*-^ The  sexes  of  other 
pachydermatous  animals  differ  very  little  or  not  at  all,  and, 
as  far  as  known,  they  are  not  polygamists.  Nor  have  I 
heard  of  any  species  in  the  orders  of  Cheiroptera,  Edentata, 
Insectivora  and  Rodents  being  polygamous,  excepting  that 
among  the  Rodents,  the  common  rat,  according  to  some 
rat-catchers,  lives  with  several  females.  Nevertheless  the 
two  sexes  of  some  sloths  (Edentata)  differ  in  the  character 
and  color  of  certain  patches  of  hair  on  their  shoulders,  f 
And  many  kinds  of  bats  (Cheiroptera)  present  well- 
marked  sexual  differences,  chiefly  in  the  males  possessing 
odoriferous  glands  and  pouches,  and  by  their  being  of 
a  lighter  color.  J  In  the  great  order  of  Rodents,  as  far  as  I 
can  learn,  the  sexes  rarely  differ,  and  when  they  do  so  it 
is  but  slightly  in  the  tint  of  the  fur. 

As  I  hear  from  Sir  Andrew  Smith,  the  lion  in  S.  Africa 
sometimes  lives  with  a  single  female,  but  generally  with 
more,  and,  in  one  case,  was  found  with  as  many  as  five 
females;  so  that  he  is  polygamous.  As  far  as  I  can  dis- 
cover he  is  the  only  polygamist  among  all  the  terrestrial 
Camivora,  and  he  alone  presents  well-marked  sexual  char- 
acters. If,  however,  we  turn  to  the  mai-ine  Carnivora,  as 
we  shall  hereafter  see,  the  case  is  widely  different;  for  many 
species  of  seals  offer  extraordinary  sexual  differences, 
and  they  are  eminently  polygamous.  Thus,  according  to 
Peron,  the  male  sea -elephant  of  the  Southern  Ocean 
always  possesses  several  females,  and  the  sea-lion  of  Forster 
is  said  to  be  surrounded  by  from  twenty  to  thirty  females. 
In  the  North  the  male  sea-bear  of  Steller  is  accompanied 
by  even  a  greater  number  of  females.  It  is  an  interesting 
fact,  as  Dr.  Gill  remarks,  §  that  in  the  monogamous  species, 
"  or  those  living  in  small  communities,  there  is  little  differ- 
ence in  size  between  the  males  and  females;  in  the  social 
species,  or  rather  those  of  which  the  males  have  harems, 
the  males  are  vastly  larger  than  the  females. '^ 

*Dr.  Campbell,  in  '' Proc.  Zoolog.  Soc.,"  1869,  p.  138.  See  also 
an  interesting  paper,  by  Lieut.  Johnstone,  in  "  Proc.  Asiatic  Soc.  of 
Bengal,"  May,  1868. 

t  Dr.  Gray,  in  "Annals  and  Mag.  of  Nat.  Hist.,"  1871,  p.  302. 

JSee  Dr.  Dobson's  excellent  paper  in  "  Proc.  Zoolog.  Soc.,"  1873, 
p.  241. 

§Tlie  Blared  Seals,  "  American  Naturalist,"  vol.  iv,  Jan.,  1871. 


248  THE  DESCENT  OP  MAN. 

Among  birds,  many  species,  the  sexes  of  which  differ 
greatly  from  each  other,  are  certainly  monogamous.  In 
Great  Britain  we  see  well-marked  sexual  differences,  for 
instance,  in  the  wild  duck  which  pairs  with  a  single  female, 
the  common  blackbird,  and  the  bullfinch  which  is  said  to 
pair  for  life.  I  am  informed  by  Mr.  Wallace  that  the  like 
is  true  of  the  Chatterers  or  Cotingid^e  of  South  America, 
and  of  many  other  birds.  In  several  groups  I  have  not. 
been  able  to  discover  whether  the  species  are  polygamous  or 
monogamous.  Lesson  says  that  birds  of  paradise,  so 
remarkable  for  their  sexual  differences,  are  polygamous,  but 
Mr.  Wallace  doubts  whether  he  had  sufficient  evidence. 
Mr.  Salvin  tells  me  he  has  been  led  to  believe  that  hum- 
ming -  birds  are  polygamous.  The  male  widow  -  bird, 
remarkable  for  his  caudal  plumes,  certainly  seems  to  be  a 
polygamist.*  I  have  been  assured  by  Mr.  Jenner  Weir  and 
by  others  that  it  is  somewhat  common  for  three  starlings  to 
frequent  the  same  nest;  but  whether  this  is  a  case  of 
polygamy  or  polyandry  has  not  been  ascertained. 

The  Gallinacese  exhibit  almost  as  strongly  marked  sexual 
differences  as  birds  of  paradise  or  humming-birds,  and 
many  of  the  species  are,  as  is  well  known,  polygamous; 
others  being  strictly  monogamous.  What  a  contrast  is  pre- 
sented between  the  sexes  of  the  polygamous  peacock  or 
pheasant,  and  the  monogamous  guinea-fowl  or  partridge! 
Many  similar  cases  could  be  given,  as  in  the  grouse  tribe, 
in  which  the  males  of  the  polygamous  capercailzie  and 
black-cock  differ  greatly  from  the  females;  while  the  sexes 
of  the  monagamous  red  grouse  and  ptarmigan  differ  very 
little.  In  the  Cursores,  except  among  the  bustards,  few 
species  offer  strongly-marked  sexual  differences,  and  the 
great  bustard  ( Otis  tarda)  is  said  to  be  polygamous.  With 
the  Grallatores  extremely  few  species  differ  sexually,  but 
the  ruff'  {Machetes  piignax)  affords  a  marked  exception  and 
this  species  is  believed  by  Montagu  to  be  a  polygamist. 
Hence  it  appears  that  among  birds  there  often  exists  a  close 
relation  between  polygamy  and  the  development  of  strongly- 

*"The  Ibis,"  vol.  iii,  1861,  p.  133,  on  the  Progne  Widow-bird. 
See  also  on  tlie  Vidua  axillaHs,  ibid.,  vol.  ii,  1860,  p.  211.  On  the 
polygamy  of  tlie  Capercailzie  and  (jreat  Bustard,  see  Ij.  Lloyd, 
"Game  Birds  of  Sweden,"  1867,  pp.  19,  183.  Montagu  and  Selby 
speak  of  the  Black  Grouse  as  polygamous  and  of  the  Red  Grouse  as 
monogamous. 


8BLUAL  SELECTION.  249 

marked  sexual  differences.  I  asked  Mr.  Bartlett,  of  the 
Zoological  Gardens,  who  has  had  very  large  experience 
with  birds,  whether  the  male  tragopan  (one  of  the  Gallin- 
aceae)  was  polygamous,  and  I  was  struck  by  his  answering, 
*'  I  do  not  know,  but  should  think  so  from  his  splendid 
colors/' 

It  deserves  notice  that  the  instinct  of  pairing  with  a  single 
female  is  easily  lost  under  domestication.  The  wild-duck 
is  strictly  monogamous,  the  domestic  duck  highly  polyga- 
mous. The  Rev.  W.  I).  Fox  informs  me  that  out  of  some 
half-tamed  wild-ducks,  on  a  large  pond  in  his  neighbor- 
hood, so  many  mallards  were  shot  by  the  gamekeeper  that 
only  one  was  left  for  every  seven  or  eight  females;  yet 
unusually  large  broods  were  reared.  The  guinea-fowl  is 
strictly  monogamous;  but  Mr.  Fox  finds  that  his  birds  suc- 
ceed best  when  he  keeps  one  cock  to  two  or  three  hens. 
Canary-birds  pair  in  a  state  of  nature,  but  the  breeders  in 
England  successfully  put  one  male  to  four  or  five  females. 
I  have  noticed  these  cases  as  rendering  it  probable  that 
wild  monogamous  species  might  readily  become  either  tem- 
porarily or  permanently  polygamous. 

Too  little  is  known  of  the  habits  of  reptiles  and  fishes 
to  enable  us  to  speak  of  their  marriage  arrangements.  The 
stickle-back  (Gasterosteus),  however,  is  said  to  be  a  polyg- 
amist;*  and  the  male  during  the  breeding  season  differs 
conspicuously  from  the  female. 

^J'o  sum  up  on  tlie  means  through  which,  as  far  as  we  can 
judge,  sexual  selection  has  led  to  the  development  of  second- 
ary sexual  characters.  /,  It  has  been  shown  that  the  largest 
number  of  vigorous  offspring  will  be  reared  from  the  pair- 
ing of  the  strongest  and  best-armed  males,  victorious  in 
contests  over  other  males,  with  the  most  vigorous  and  best- 
nourished  females,  which  are  tlie  first  to  breed  in  the  spring.  A 
If  such  females  select  the  more  attractive,  and  at  the  same 
time  vigorous  males,  they  will  rear  a  larger  number  of  off'- 
spring  than  the  retarded  females,  which  must  pair  with  the 
less  vigorous  and  less  attractive  males.  So  it  will  be  if  the 
more  vigorous  males  select  the  more  attractive  and  at  the 
same  time  healthy  and  vigorous  females;  and  this  will  espe- 
cially hold  good  if  the  male  defends  the  female  and  aids 
in  providing  food  for   the   young.     The   advantage  thus 

*Noel  Humplireys,  "  River  Gardens,"  1857. 


:^50  "ttiti  MSCMT  OP'  MAN, 

gairte^d  by  the  more  vigorous  pairs  in  rearing  a  Ittrgei 
number  of  offspring  lias  apparently  sufficed  to  render  sex- 
ual selection  efficient,  liut  a  large  numei-ical  preponder- 
ance of  males  over  females  will  be  still  more  efficient; 
whether  the  preponderance  is  only  occasional  and  local,  or 
permanent;  whether  it  occurs  at  birth,  or  afterward  from 
the  greater  destruction  of  the  females;  or  whether  it  in- 
directly follows  from  the  practice  of  polygamy. 

r  The  Mate  Generallj/  More  Modified  than  the  Female. — 
xhroughout  the  animal  kingdom  when  the  sexes  differ 
in  external  appearance,  it  is,  with  rare  exceptions,  the  male 
which  has  been  the  more  modified;  for,  generally,  the 
female  retains  a  closer  resemblance  to  the  young  of  her  own 
species  and  to  other  adult  members  of  the  same  group. 
The  cause  of  this  seems  to  lie  in  the  males  of  almost  all 
animals  having  stronger  passions  than  the  females.  Hence 
it  is  the  males  that  fight  together  and  sedulously  display 
their  charms  before  the  females;  and  the  victors  transmit 
their  superiority  to  their  male  offspring.  Why  both  sexes 
do  not  thus  acquire  the  characters  of  their  fathers  will  be 
considered  hereafter.  That  the  males  of  all  mammals 
eagerly  pursue  the  females  is  notorious  to  every  one.  So  it 
is  with  birds;  but  many  cock  birds  do  not  so  much  pursue 
the  hen,  as  display  their  plumage,  perform  strange  antics, 
and  pour  forth  their  song  in  her  presence.  The  male  in  the 
few  fish  observed  seems  much  more  eager  than  the  female; 
aiul  the  same  is  true  of  alligators,  and  apparently  of 
Batrachians.  Throughout  the  enormous  class  of  insects, 
as  Kirby  remarks, 't.''  the  law  is  that  the  male  shall  seek  the 
female. ""3 Two  good  authorities,  Mr.  Blackwall  and  Mr.  C. 
Spence  l^te,  tell  me  that  the  males  of  spiders  aiul  crusta- 
ceans are  mom  active  and  more  erratic  in  their  habits  than 
tlie  females.  uiV^hen  the  organs  of  sense  or  locomotion  are 
present  in  the  one  sex  of  insects  and  crustaceans  and  absent 
in  the  other,  or  when,  as  is  frerjuently  tlie  case,  they  are 
more  highly  developed  in  the  one  than  in  the  other,  it  is,  as 
far  as  I  can  discover,  almost  invariably  the  nude  which 
retains  such  organs,  or  has  them  most  developed;  and  this 


*  Kirby  and  Spence,  •'  Introduction  to  Entoinolo^v,"  vol    iii,  1836, 
J).  '642 


BUXUAL  SELkCTIOM.  ^51 

Bhows  that  the  male  is  the  more  active  member  in  the 
courtship  of  the  sexes.  *3 

The  female,  on  the  other  hand,  with  the  rarest  excep- 
tions, is  less  eager  than  the  male.  As  the  illustrious 
Hunter  f  long  ago  observed  she  generally  "  requires  to  be 
courted;"  she  is  coy,  and  may  often  be  seen  endeavoring  for 
a  long  time  to  escape  from  the  male.  Every  observer  of 
the  habits  of  animals  will  be  able  to  call  to  mind  instances 
of  this  kind.  It  is  shown  by  various  facts,  given  hereafter, 
and  by  the  results  fairly  attributable  to  sexual  selection, 
that  the  female,  though  comparatively  passive,  generally 
exerts  some  choice  and  accepts  one  male  in  preference  to 
others.  Or  she  may  accept,  as  appearances  would  some- 
times lead  us  to  believe,  not  the  male  which  is  the  most 
attractive  to  her,  but  the  one  which  is  the  least  dis- 
tasteful. The  exei-tion  of  some  choice  on  the  part  of  the 
female  seems  a  law  almost  as  general  as  the  eagerness  of  the 
male. 

We  are  naturally  led  to  inquire  why  the  male,  in  so 
many  and  such  distinct  classes,  has  become  more  eager 
than  the  female,  so  that  he  searches  for  her  and  plays 
the  more  active  part  in  courtship.  It  would  be  no 
advantage  and  some  loss  of  power  if  each  sex  searched 
for  the  other;  but  why  should  the  male  almost  always  be 
the  seeker?  The  ovules  of  plants  after  fertilization  have 
to  be  nourished  for  a  time;  hence  the  pollen  is  necessarily 
brought  to  the  female  organs — being  placed  on  the  stigma, 
by  means  of  insects  or  the  wind,  or  by  the  spontaneous 
movements  of  the  stamens;  and  in  the  Algae,  etc.,  by  the 
locomotive  power  of  the  antherozooids.  With  lowly-organ- 
ized aquatic  animals,  permanently  affixed  to  the  same  spot 
and  having  their  sexes  separate,  the  male  element  is  invari- 
ably brought   to  the   female;  and  of  this  we  can  see  the 

*  One  parasitic  Hymenopterous  insect  (Westwood,  "  Modem  Class, 
of  Insects,"  vol.  ii,  p.  160)  forms  an  exception  to  the  rule,  as  the 
male  has  rudimentary  wings,  and  never  quits  the  cell  in  which  it  is 
born,  while  the  female  has  well-developed  wings.  Audouin  believes 
that  the  females  of  this  species  are  impregnated  by  the  males  which 
are  born  in  the  same  cells  with  them;  but  it  is  much  more  probable 
that  the  females  visit  other  cells,  so  that  close  interbreeding  is  thus 
avoided.  We  shall  hereafter  meet  in  various  classes,  with  a  few 
exceptional  cases,  in  which  the  female,  instead  of  the  male,  is  the 
seeker  and  wooer. 

f  "Essays  and  Observations,"  edited  by  Owen,  vol.  i,  1861,  p.  194. 


25^  THE  DESCENT  OF  MAN. 

reason^  for  even  if  the  ova  were  detached  before  fertiliza- 
tion, and  did  not  require  subsequent  nourishment  or  pro- 
tection, there  would  yet  be  greater  difficulty  in  transorting 
them  than  the  male  element,  because,  being  larger  than 
the  latter,  they  are  produced  in  far  smaller  numbers.  So 
that  many  of  the  lower  animals  are,  in  this  respect,  analo- 
gous with  plants.*  The  males  of  affixed  and  aquatic  ani- 
mals having  been  led  to  emit  their  fertilizing  elements  in 
this  way,  it  is  natural  that  any  of  their  descendants,  which 
rose  in  the  scale  and  became  locomotive,  should  retain  the 
same  habit;  and  they  would  approach  the  female  as  closely 
as  possible,  in  order  not  to  risk  the  loss  of  the  fertilizing 
element  in  a  long  passage  of  it  through  the  water.  With 
some  few  of  the  lower  animals,  the  females  alone  are  fixed, 
and  the  males  of  these  must  be  the  seekers.  But  it  is  dif- 
ficult to  understand  why  the  males  of  species,  of  which  the 
progenitors  were  primordially  free,  should  invariably  have 
acquired  the  habit  of  approaching  the  females,  instead  of 
being  approached  by  them.  But  in  all  cases,  in  order  that 
the  males  should  seek  efficiently,  it  would  be  necessary  that 
they  should  be  endowed  with  strong  passions;  (and  the 
acquirement  of  such  passions  would  naturally  follow  from 
the  more  eager  leaving  a  larger  number  of  offspring  than 
the  less  eager.  ^ 

[jlie  great  eagerness  of  the  males  has  thus  indirectly  led 
to  their  much  more  frequently  developing  secondary  sexual 
characters  than  the  females.  But  the  development  of  such 
chai'acters  would  be  much  aided,  if  the  males  were  more 
liable  to  vary  than  the  females — as  I  concluded  they  were — 
after  a  long  study  of  domesticated  animals.  A  Von  Nathu- 
sius,  who  has  had  very  wide  experience,  is  s^'ongly  of  the 
same  opinion,  f  Good  evidence  also  in  favor  of  this  con- 
clusion can  be  produced  by  a  comparison  of  the  two  sexes 
in   mankind.     J3uring    the    No  vara    Expedition  J;  a    vast 

*Prof.  Sachs  ("  Lehrbuch  der  Botanik,"  1870,  s.  638),  in  speaking 
of  the  male  and  female  reproductive  cells,  remarks,  '•  verhalt  sich 
die  eine  bei  der  Vereinigung  activ,  .  .  .  die  andere  erscheint  bei 
der  Vereinigung  passiv." 

t"  Vortrage  uber  Viehzucht,"  1872,  p.  63. 

X  "Reise  der  Novara,  Anthro])olog.  Theil,"  1867,  ss.  216-269.  The 
results  were  calculated  by  Dr.  Weisbach  from  measurements  made 
by  Drs.  K.  Scher/er  and  Schwarz.  On  the  greater  variability  of  the 
males  of  domesticated  animals,  see  my  *'  Variation  of  Animals  and 
Plants  under  Domestication,"  vol.  ii,  1868,  p.  75. 


SEXUAL  SELECTION.  253 

number  of  measurements  was  made  of  various  parts  of  the 
body  in  different  races,  and  the  men  were  found  in  almost 
every  case  to  present  a  greater  range  of  variation  than 
tlie  women  ;  but  I  shall  have  to  recur  to  this  subject  in 
a  future  chapter.  Mr.  J.  Wood,*  who  has  carefully 
attended  to  the  variation  of  the  muscles  in  man,  puts  in 
italics  the  conclusion  that  "  the  greatest  number  of 
abnormalities  in  each  subject  is  found  in  the  males."  He 
had  previously  remarked  that  "altogether  in  102  subjects, 
the  varieties  of  redundancy  were  found  to  be  half  as  many 
again  as  in  females,  contrasting  widely  with  the  greater 
frequency  of  deficiency  in  females  before  described."  Prof. 
Macalister  likewise  remarksf  that  variations  in  the  muscles 
"are  probably  more  common  in  males  than  females." 
Certain  muscles  which  are  not  normally  present  in  man- 
kind are  also  more  frequently  developed  in  the  male  than 
in  the  female  sex,  although  exceptions  to  this  rule  are  said 
to  occur.  Dr.  Burt  Wilder];  has  tabulated  the  cases  of  152 
individuals  with  supernumerary  digits,  of  which  86  were 
males  and  39,  or  less  than  half,  females,  the  remaining  27 
being  of  unknow  sex.  It  should  not,  however,  be  over- 
looked that  women  would  more  frequently  endeavor  to  con- 
ceal a  deformity  of  this  kind  than  men.  Again,  Dr.  L. 
Meyer  asserts  that  the  ears  of  man  are  more  variable  in 
form  than  those  of  a  woman.  §  Lastly,  the  temperature  is 
more  variable  in  man  than  in  woman,  n 

The  cause  of  the  greater  general  variability  in  the  male 
sex  than  in  the  female  is  unknown,  except  in  so  far  as  sec- 
ondary sexual  characters  are  extraordinarily  variable  and 
are  usually  confined  to  the  males;  and,  as  we  shall  presently 
see,  this  fact  is,  to  a  certain  extent,  intelligible.  Through 
the  action  of  sexual  and  natural  selection  male  animals 
have  been  rendered  in  very  many  instances  widely  different 
from  their  females ;  but  independently  of  selection  the 
two  sexes,  from  differing  constitutionally,  tend  to  vary  in 

*  "  Proceedings  Royal  Soc,"  vol.  xvi;  July,  1868.  pp.  519,  534. 

•I-  "  Proc.  Royal  Irish  Academy,"  vol.  x,  1868,  p.  123. 

X  "  Massachusetts  Medical  Soc,"  vol.  ii,  No.  3,  1868,  p.  9. 

§  "  Archiv  fiir  Path.  Anat.  und  Phys.,"  1871,  p.  488. 

I  The  conclusions  recently  arrived  at  by  Dr.  J.  Stockton  Hough,  on 
the  temperature  of  man,  are  given  in  the  "  Pop.  Science  Review," 
Jan.  1,  1874,  p.  97 


264  THE  DESCENT  OF  MAN. 

a  somewhat  different  manner.  The  female  has  to  expend 
much  organic  matter  in  the  formation  of  her  ova,  whereas 
the  male  expends  much  force  in  fierce  contests  with  his 
rivals,  in  wandering  about  in  search  of  the  female,  in  exert- 
ing his  voice,  pouring  out  odoriferous  secretions,  etc. ;  and 
this  expenditure  is  generally  concentrated  within  a  short 
period.  The  great  vigor  of  the  male  during  the  season  of 
love  seems  often  to  intensify  his  colors  independently  of 
any  marked  difference  from  the  female.*  In  mankind, 
and  even  as  low  down  in  the  organic  scale  as  in  the  Lepi- 
doptera,  the  temperature  of  the  body  is  higher  in  the  male 
than  in  the  female,  accompanied  in  the  case  of  man  by  a 
slower  pulse,  f  On  the  whole,  the  expenditure  of  matter 
and  force  by  the  two  sexes  is  probably  nearly  equal,  though 
effected  in  very  different  ways  and  at  different  rates. 

From  the  causes  just  specified  the  two  sexes  can  hardly 
fail  to  differ  somewhat  in  constitution,  at  least  during  the 
breeding  season;  and  although  they  may  be  subjected  to 
exactly  the  same  conditions  they  will  tend  to  vary  in  a 
different  manner.  If  such  variations  are  of  no  service  to 
either  sex  they  will  not  be  accumulated  and  increased  by 
sexual  or  natural  selection.  Nevertheless,  they  may  be- 
come permanent  if  the  exciting  cause  acts  permanently; 
and  in  accordance  with  a  frequent  form  of  inheritance 
they  may  be  transmitted  to  that  sex  alone  in  wliich  they 
first  appeared.  In  this  case  the  two  sexes  will  come  to 
present  permanent,  yet  unimportant,  differences  of  char- 
acter. For  instance,  Mr.  Allen  shows  that  with  a  large 
number  of  birds  inhabiting  the  northern  and  southern 
United  States,  the  specimens  from  the  south  are  darker- 
colored  than  those  from  the  north;  and  this  seems  to  be 
the  direct  result  of  the  difference  in  temperature,  light,  etc., 
between  the  two  regions.     Now,  in  some  few  cases,  the 

*Prof.  Mantegazza  is  inclined  to  believe  ("  Lettera  a  Carlo  Dar- 
win," '*  Arcbivio  per  I'Antbropologia,"  1871,  p.  306)  tbat  tbe  brigbt 
colors,  common  in  so  many  male  animals,  are  due  to  tbe  presence  and 
retention  by  tbera  of  tbe  spermatic  fluid;  but  tbis  can  bardly  be  tbe 
case;  for  many  male  birds,  for  instance  young  pbeasants,  become 
briglitly  colored  in  tbe  autumn  of  tbeir  first  year. 

f  For  mankind,  see  Dr.  J.  Stockton  Hougb,  wbose  conclusions  are 
given  in  tbe  "  Pop,  Science  Review,"  1874,  p.  97.  See  Girard's 
observations  on  tbe  Lepidoptera,  as  given  in  tbe  "Zoological  Record," 
1869,  p.  347. 


SEXUAL  SELECTION.  265 

two  sexes  of  the  same  species  appear  to  have  been  diifer- 
ently  affected;  in  the  Agelcens  phceniceus  the  males  have 
had  their  colors  greatly  intensified  in  the  south;  whereas 
with  Gardinalis  virginiayius  it  is  the  females  which  have 
been  thus  affected;  with  Qniscalns  major  the  females  have 
been  rendered  extremely  variable  in  tint,  while  the  males 
remain  nearly  uniform.* 

A  few  exceptional  cases  occur  in  various  classes  of  ani- 
mals, in  which  the  females  instead  of  the  males  have 
acquired  well-pronounced  secondary  sexual  characters,  such 
as  brighter  colors,  greater  size,  strength  or  pugnacity. 
With  birds  there  has  sometimes  been  a  complete  transposi- 
tion of  the  ordinary  characters  proper  to  each  sex;  the 
females  having  become  the  more  eager  in  courtship,  the 
males  remaining  comparatively  passive,  but  apparently 
selecting  the  more  attractive  females,  as  we  may  infer  from 
the  results.  Certain  hen  birds  have  thus  been  rendered 
more  highly  colored  or  otherwise  ornamented,  as  well  as 
more  powerful  and  pugnacious  than  the  cocks ;  these 
characters  being  transmitted  to  the  female  offspring  alone. 

It  may  be  suggested  that  in  some  cases  a  double  process 
of  selection  has  been  carried  on;  that  the  males  have  selected 
the  more  attractive  females  and  the  latter  the  more  attract- 
ive males.  This,  process,  however,  though  it  might  lead 
to  the  modification  of  both  sexes,  would  not  make  the  one 
sex  different  from  the  other,  unless  indeed  their  tastes  for 
the  beautiful  differed;  but  this  is  a  supposition  too  improba- 
ble to  be  worth  considering  in  the  case  of  any  animal,  except- 
ing man.  There  are,  however,  many  animals  in  which  the 
sexes  resemble  each  other,  both  being  furnished  with  the 
same  ornaments,  which  analogy  would  lead  us  to  attribute 
to  the  agency  of  sexual  selection.  In  such  cases  it  may  be 
suggested  with  more  plausibility  that  there  has  been  a 
double  or  mutual  process  of  sexual  selection;  the  more 
vigorous  and  precocious  females  selecting  the  more 
attractive  and  vigorous  males,  the  latter  rejecting  all 
except  the  more  attractive  females.  But  from  what  we 
know  of  the  habits  of  animals,  this  view  is  hardly  probable, 
for  the  male  is  generally  eager  to  pair  with  any  female.  It 
is  more  probable  that  the  ornaments  common  to  both  sexes 
were   acquired   by  one  sex,  generally  the  male,  and  then 

*  "  Mauamals  and  Birds  of  E.  Floida,"  pp.  234,  280,  29§. 


256  THE  DESCENT  OF  MAN. 

transmitted  to  the  offspring  of  both  sexes.  If,  indeed, 
during  a  lengthened  period  the  males  of  any  species  were 
greatly  to  exceed  the  females  in  number,  and  then  during 
another  lengthened  period,  but  under  different  conditions, 
the  reverse  were  to  occur,  a  double,  but  not  simultaneous, 
process  of  sexual  selection  might  easily  be  carried  on,  by 
which  the  two  sexes  might  be  rendered  widely  different. 

We  shall  hereafter  see  that  many  animals  exist,  of  which 
neither  sex  is  brilliantly  colored  or  provided  with  special 
ornaments,  and  yet  the  members  of  both  sexes  or  of  one 
alone  have  probably  acquired  simple  colors,  such  as  white 
or  black,  through  sexual  selection.  The  absence  of  bright 
tints  or  other  ornaments  may  be  the  result  of  variations  of 
the  right  kind  never  having  occurred,  or  of  the  animals 
themselves  having  preferred  plain  black  or  white.  Obscure 
tints  have  often  been  developed  through  natural  selection  for 
the  sake  of  protection,  and  the  acquirement  through  sexual 
selection  of  conspicuous  colors  appears  to  have  been  some- 
times checked  from  the  danger  thus  incurred.  But  in 
other  cases  the  males  during  long  ages  may  have  struggled 
together  for  the  possession  of  the  females,  and  yet  no  effect 
will  have  been  produced,  unless  a  larger  number  of 
offspring  were  left  by  the  more  successful  males  to  inherit 
their  superiority  than  by  the  less  successful;  and  this,  as 
previously  shown,  depends  on  many  complex  contingencies. 

Sexual  selection  acts  in  a  less  rigorous  manner  than 
natural  selection.  The  latter  produces  its  effects  by  the 
life  or  death  at  all  ages  of  the  more  or  less  successful  indi- 
viduals. Death,  indeed,  not  rarely  ensues  from  the 
conflicts  of  rival  males.  But  generally  the  less  successful 
male  merely  fails  to  obtain  a  female,  or  obtains  a  retarded 
and  less  vigorous  female  later  in  the  season,  or,  if  polyga- 
mous, obtains  fewer  females;  so  that  they  leave  fewer,  less 
vigorous,  or  no  offspring.  In  regard  to  structures  acquired 
through  ordinary  or  natural  selection  there  is  in  most  cases, 
as  long  as  the  conditions  of  life  remain  the  same,  a  limit  to 
the  amount  of  advantageous  modification  in  relation  to 
certain  special  purposes;  but  in  regard  to  structures  adapted 
to  make  one  male  victorious  over  another,  either  in  fighting 
or  in  charming  the  female,  there  is  no  definite  limit  to  the 
amount  of  advantageous  modification;  so  that  as  long  as 
the  proper  variations  arise  the  work  of  sexual  selection  will 
go   on.     This   circumstance   may  partly  account  for   the 


SEXUAL  SELECTION.  257 

frequent  and  extraordinary  amount  of  variability  presented 
by  secondary  sexual  characters.  Nevertheless,  natural 
selection  will  determine  that  such  characters  shall  not  be 
acquired  by  the  victorious  males,  if  they  would  be  highly 
injurious,  either  by  expending  too  much  of  their  vital 
powers  or  by  exposing  them  to  any  great  danger.  The 
development,  however,  of  certain  structures — of  the  horns, 
for  instance,  in  certain  stags — has  been  carried  to  a  won- 
derful extreme;  and  in  some  cases  to  an  extreme  which,  as 
far  as  the  general  conditions  of  life  are  concerned,  must  be 
slightly  injurious  to  the  male.  From  this  fact  we  learn 
that  the  advantages  which  favored  males  derive  from  con- 
quering other  males  in  battle  or  courtship,  and  thus  leaving 
a  numerous  progeny,  are  in  the  long  run  greater  than  those 
derived  from  rather  more  perfect  adaptation  to  their  condi- 
tions of  life.  We  shall  further  see,  and  it  could  never  have 
been  anticipated,  that  the  power  to  charm  the  female  has 
sometimes  been  more  important  than  the  power  to  conquer 
other  males  in  battle.  i 

Latos  of  Inheritance. — In  order  to  understand  how  sexual 
selection  has  acted  on  many  animals  of  many  classes,  and 
in  the  course  of  ages  has  produced  a  conspicuous  result,  it 
is  necessary  to  bear  in  mind  the  laws  of  inheritance  as  far 
as  they  are  known.  Two  distinct  elements  are  included 
under  the  term  '^inheritance"'' — the  transmission  and  the 
development  of  characters ;  but  as  these  generally  go 
together  the  distinction  is  often  overlooked.  We  see  this 
distinction  in  those  characters  which  are  transmitted 
through  the  early  years  of  life,  but  are  developed  only  at 
maturity  or  during  old  age.  We  see  the  same  distinction 
more  clearly  with  secondary  sexual  characters,  for  these  are 
transmitted  through  both  sexes,  though  developed  in  one 
alone.  That  they  are  present  in  both  sexes  is  manifest 
when  two  species  having  strongly  marked  sexual  characters 
are  crossed,  for  each  transmits  the  characters  proper  to  its 
own  male  and  female  sex  to  the  hybrid  offspring  of  either 
sex.  The  same  fact  is  likewise  manifest  when  characters 
proper  to  the  male  are  occasionally  developed  in  the  female 
when  she  grows  old  or  becomes  diseased,  as,  for  instance, 
when  tlie  common  hen  assumes  the  flowing  tail-feathers, 
hackles,  comb,  spurs,  voice,  and  even  pugnacity  of  the 
cock.     Conversely  the  same  thing  is  evident  more  or  less 


258  THE  DESCENT  OF  MAN, 

plainly  with  castrated  males.  Again,  independently  of 
old  age  or  disease,  characters  are  occasionally  transferred 
from  the  male  to  the  female,  as  when  in  certain  breeds  of 
the  fowl  spurs  regularly  appear  in  the  young  and  healthy 
females.  But  in  truth  they  are  simply  developed  in  the 
female;  for  in  every  breed  each  detail  in  the  structure  of 
the  spur  is  transmitted  through  the  female  to  her  male  off- 
spring. Many  cases  will  hereafter  be  given  where  the 
female  exhibits  more  or  less  perfectly  characters  proper  to 
the  male,  in  whom  they  must  have  been  first  developed  and 
then  transferred  to  the  female.  The  converse  case  of  the 
lirst  development  of  characters  in  the  female  and  of  trans- 
ference to  the  male  is  less  frequent;  it  will  therefore  be 
well  to  give  one  striking  instance.  With  bees  the  pollen- 
collecting  apparatus  is  used  by  the  female  alone  for  gather- 
ing pollen  for  the  larvae,  yet  in  most  of  the  species  it  is 
partially  developed  in  the  males  to  whom  it  is  quite  useless, 
and  it  is  perfectly  developed  in  the  males  of  Bombus  or  the 
humble-bee.*  As  not  a  single  other  Hymenopterous  insect, 
not  even  the  wasp,  which  is  closely  allied  to  the  bee,  is 
provided  with  a  pollen-collecting  apparatus,  we  have  no 
grounds  for  supposing  that  male  bees  primordially  collected 
pollen  as  well  as  the  females;  although  we  have  some  reason 
to  suspect  that  male  mammals  primordially  suckled  their 
young  as  well  as  the  females.  Lastly,  in  all  cases  of  rever- 
sion characters  are  transmitted  through  two,  three  or  many 
more  generations,  and  are  then  developed  under  certain 
unknown  favorable  conditions.  This  important  distinction 
between  transmission  and  development  will  be  best  kept  in 
mind  by  the  aid  of  the  hypothesis  of  pangenesis.  Accord- 
ing to  this  hypothesis  every  unit  or  cell  of  the  boby  throws 
off  gemmules  or  undeveloped  atoms  which  are  transmitted 
to  the  offspring  of  both  sexes  and  are  multiplied  by  self- 
division.  They  may  remain  undeveloped  during  the  early 
years  of  life  or  during  successive  generations;  and  their 
development  into  units  or  cells,  like  those  from  which  they 
were  derived,  depends  on  their  affinity  for  and  union  with 
other  units  or  cells  previously  developed  in  the  due  order 
of  growth. 
Inheritance  at  Corresponding   Periods  of  Life. — This 

*  H.  Miiller,  "  Anwendung  der  Durwiu'scben  Lehre,"  etc.     Verb, 
d.  n.  V.  Jahrg.  xxix,  p.  42. 


SEXUAL  SELECTION.  259 

tendency  is  well-established.  A  new  character,  appearing 
in  a  young  animal,  whether  it  lasts  throughout  life  or  is 
only  transient,  will,  in  general,  reappear  in  the  offspring  at 
the  same  age  and  last  for  the  same  time.  If,  on  the  other 
hand,  a  new  character  appears  at  maturity,  or  even  during 
old  age,  it  tends  to  reappear  in  the  offspring  at  the  same 
advanced  age.  AVhen  deviations  from  this  rule  occur,  the 
transmitted  characters  much  oftener  appear  before,  than 
after  the  corresponding  age.  As  I  have  dwelt  on  this  sub- 
ject sufficiently  in  another  work,*  I  will  here  merely  give 
two  or  three  instances,  for  the  sake  of  recalling  the  subject 
to  the  reader's  mind.  In  several  breeds  of  the  fowl,  the 
down-covered  chickens,  the  young  birds  in  their  first  true 
plumage,  and  the  adults  differ  greatly  from  one  another,  as 
well  as  from  their  common  parent-form,  the  G alius  hankiva; 
and  these  characters  are  faithfully  transmitted  by  each 
breed  to  their  offspring  at  the  corresponding  periods  of 
life.  For  instance,  the  chickens  of  spangled  Hamburgs, 
while  covered  with  down,  have  a  few  dark  spots  on  the 
head  and  rump,  but  are  not  striped  longitudinally,  as  in 
many  other  breeds;  in  their  first  true  plumage,  "  they  are 
beautifully  penciled,"  that  is,  each  feather  is  transversely 
marked  by  numerous  dark  bars;  but  in  their  second  plum- 
age the  feathers  all  become  spangled  or  tipped  with  a  dark 
round  spot.f  Hence  in  this  breed  variations  have. occurred 
at,  and  transmitted  to,  three  distinct  periods  of  life.  The 
pigeon  offers  a  more  remarkable  case,  because  the  aborigi- 
nal parent-species  does  not  undergo  any  change  of  plumage 
w^ith  advancing  age,  excepting  that  at  maturity  the  breast 
becomes  more  iridescent ;  yet  there  are  breeds  which  do 
not  acquire  their  characteristic  colors  until  they  have 
moulted  two,  three,  or  four  times;  and  these  modifications 
of  plumage  are  regularly  transmitted. 

Inheritance  at  Corresponding  Seasons  of  the  Year. — With 

*  "  The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  1868,  p.  75.  In  tlie  last  chapter  but  one  the  provisional  hypo- 
thesis of  pangenesis,  above  alluded  to,  is  fully  explained. 

f  These  facts  are  given  on  the  high  authority  of  a  great  breeder, 
Mr.  Teebay;  see  Tegetmeier's  "  Poultry  Book,"  1868,  p.  158.  On 
the  characters  of  chickens  of  different  breeds,  and  on  the  breeds  of 
the  pigeon,  alluded  to  in  the  following  paragraph,  see  "  Variation  of 
Animals,"  etc.,  vol.  i,  pp.  160,  249;  vol.  ii,  p.  77. 


2G0  THE  DESCENT  OF  MAN. 

animals  in  a  state  of  nature,  inniimenible  instances  occur 
of  characters  appearing  periodically  at  different  seasons. 
We  see  this  in  the  horns  of  the  stag,  and  in  the  fur  of  the 
Arctic  animals,  which  becomes  thick  and  white  during  the 
winter.  Many  birds  acquire  bright  colors  and  other  deco- 
rations during  the  breeding-season  alone.  Pallas  states,* 
that  in  Siberia  domestic  cattle  and  horses  become  lighter- 
colored  during  the  winter;  and  I  have  myself  observed,  and 
heard  of  similar  strongly-marked  changes  of  color,  that  is, 
from  brownish-cream  color  or  reddish-brown  to  a  perfect 
white,  in  several  ponies  in  England.  Al  though  I  do  not  know 
that  this  tendency  to  change  the  color  of  the  coat  during 
diiferent  seasons  is  transmitted,  yet  it  probably  is  so,  as  all 
shades  of  color  are  strongly  inherited  by  the  horse.  Nor  is 
this  form  of  inheritance  as  limited  by  the  seasons,  more 
remarkable  than  its  limitation  by  age  or  sex. 

Inheritance  as  TAmited  by  Sex. — The  equal  transmission 
of  characters  to  both  sexes  is  the  commonest  form  of  inher- 
itance, at  least  with  those  animals  which  do  not  present 
strongly-marked  sexual  differences,  and  indeed  with  many 
of  these.  But  characters  are  somewhat  commonly  trans- 
ferred exclusively  to  that  sex  in  which  they  first  appear. 
Ample  evidence  on  this  head  has  been  advanced  in  my  work 
on  '^Variation  Under  Domestication,"  but  a  few  instances 
may  here  be  given.  There  are  breeds  of  the  sheep  and  goat, 
in  which  the  horns  of  the  male  differ  greatly  in  shape  from 
those  of  the  female;  and  these  differences  acquired  under 
domestication  are  regularly  transmitted  to  the  same  sex. 
As  a  rule,  it  is  the  females  alone  in  cats  which  are  tortoise- 
shell,  the  corresponding  color  in  the  males  being  rusty-red. 
With  most  breeds  of  the  fowl  the  characters  proper  to  each 
sex  are  transmitted  to  the  same  sex  alone.  So  general  is 
this  form  of  transmission  that  it  is  an  anomaly  when  varia- 
tions in  certain  breeds  are  transmitted  equally  to  both 
sexes.  There  are  also  certain  sub-breeds  of  the  fowl  in 
which  the  males  can  hardly  be  distinguished  from  one 
another,  while  the  females  differ  considerably  in  color. 
The  sexes  of  the  pigeon  in  the  parent-species  do  not  differ 

*  "  Novae  species  Quadrupedum  e  Glirium  ordine,"  1778,  p.  7.  On 
the  transmission  of  color  by  the  horse,  see  "  Variation  of  Animals, 
etc.,  under  Domestication."  vol.  i,  p.  51.  Also  vol.  ii,  p.  71,  for  a 
general  discussion  on  "  Inheritance  as  Limited  by  Sex." 


BEXUAL  SELWriOir.  •      ^61 

in  any  external  character;  nevertheless,  in  certain  domesti- 
cated breeds  the  male  is  colored  differently  from  the  female.  * 
The  wattle  in  the  English  carrier  pigeon  and  the  crop  in  the 
Pouter  are  more  highly  developed  in  the  male  than  in  the 
female;  and  although  these  characters  have  been  gained 
through  long-continued  selection  by  man,  the  slight  differ- 
ences between  the  sexes  are  wholly  due  to  the  form  of 
inheritance  which  has  prevailed;  for  they  have  arisen,  not 
from,  but  rather  in  opposition  to,  the  wish  of  the  breeder. 

Most  of  our  domestic  races  have  been  formed  by  the 
accumulation  of  many  slight  variations;  and  as  some  of  the 
successive  steps  have  been  transmitted  to  one  sex  alone,  and 
some  to  both  sexes,  we  find  in  the  different  breeds  of  the 
same  species  all  gradations  between  great  sexual  dissimilar- 
ity and  complete  similarity.  Instances  have  already  been 
given  with  the  breeds  of  the  fowl  and  pigeon,  and  under 
nature  analogous  cases  are  common.  With  animals  under 
domestication,  but  whether  in  nature  I  will  not  venture  to 
say,  one  sex  may  lose  characters  proper  to  it,  and  may  thus 
come  somewhat  to  resemble  the  opposite  sex;  for  instance, 
the  males  of  some  breeds  of  the  fowl  have  lost  their  mascu- 
line tail-plumes  and  hackles.  On  the  other  hand,  the  dif- 
ferences between  the  sexes  may  be  increased  under  domesti- 
cation, as  with  merino  sheep,  in  which  the  ewes  have  lost 
their  liorns.  Again,  characters  proper  to  one  sex  may  sud- 
denly appear  in  the  other  sex;  as  in  those  sub-breeds  of  the 
fowl  in  which  the  hens  acquire  spurs  while  young;  or,  as  in 
certain  Polish  sub-breeds,  in  which  the  females,  as  there  is 
reason  to  believe,  originally  acquired  a  crest,  and  subse- 
quently transferred  it  to  the  males.  All  these  cases  are 
intelligible  on  the  hypothesis  of  pangenesis;  for  they  depend 
on  the  gemmules  of  certain  parts,  although  present  in  both 
sexes,  becoming,  through  the  influence  of  domestication, 
either  dormant  or  developed  in  either  sex. 

There  is  one  difficult  question  which  it  will  be  convenient 
to  defer  to  a  future  chapter  ;  namely,  whether  a  character 
at  first  developed  in  both  sexes  could  through  selection  be 
limited  in  its  development  to  one  sex  alone.  If,  for 
instance,  a  breeder  observed  that  some  of  his  pigeons  (of 

*  Dr.  Chapuis,  "  Le  Pigeon  Voyageur  Beige,"  1865,  p.  87.  Boitard 
et  Cofbie,  "  Les  Pigeons  dc  Voliere,"  etc.,  1824,  p.  173.  See,  also, 
on  similar  differences  in  certain  breeds  at  Modena,  "  Le  variazioni  dei 
Colombi  domestici,"  del  Paolo  Bouizzi,  1873. 


262  THE  BESCENT  OF  MaM. 

which  the  characters  are  usually  transferred  in  an  equal 
degree  to  both  sexes)  varied  into  pale  blue,  could  he  by 
long-continued  selection  make  a  breed,  in  which  the  males 
alone  should  be  of  tliis  tint,  while  the  females  remained 
unchanged?  I  will  here  only  say  that  this,  though  perhaps 
not  impossible,  would  ])e  extremely  difficult;  for  the  natural 
result  of  breeding  from  the  pale-blue  males  would  be  to 
change  the  whole  stock  of  both  sexes  to  this  tint.  If, 
however,  variations  of  the  desired  tint  appeared,  which 
were  from  the  first  limited  in  their  development  to  the 
male  sex,  there  would  not  be  the  least  difficulty  in  making 
a  breed  with  the  two  sexes  of  a  diiferent  color,  as  indeed 
has  been  eifected  with  a  Belgian  breed,  in  which  the  males 
alone  are  streaked  with  black.  In  a  similar  manner,  if  any 
variation  appeared  in  a  female  pigeon,  which  was  from  the 
first  sexually  limited  in  its  development  to  the  females,  it 
would  be  easy  to  make  a  breed  with  the  females  alone  thus 
characterized;  but  if  the  variation  was  not  thus  originally 
limited  the  process  would  be  extremely  difficult,  perhaps 
impossible.* 

On  the  Relatio7i  Between  the  Period  of  Development  of  a 
Character-  and  Its  Transmission  to  (Me  Sex  or  to  Both 
Sexes. — Why  certain  characters  should  be  inherited  by  both 
sexes  and  other  characters  by  one  sex  alone,  namely,  by  that 
sex  in  which  the  character  first  appeared,  is  in  most  cases 
quite  unknown.  We  cannot  even  conjecture  why  with  cer- 
tain sub-breeds  of  the  pigeon  black  stria?,  though  trans- 
mitted through  the  female,  should  be  developed  in  the 
inale  alone,  while  every  other  character  is  equally  trans- 
ferred to  both  sexes.  Why,  again,  with  cats,  the  tortoise- 
shell  color  should,  with  rare  exceptions,  be  developed  in 
the  female  alone.  The  very  same  character,  such  as  defi- 
cient or  supernumerary  digits,  color-blindness,  etc.,  may 

*  Since  tlie  i)ul)lication  of  tlie  first  edition  of  tliis  work,  it  has  been 
highly  satisfactory  to  me  to  find  the  following  remarks  (the  "  Field," 
Sept.,  1872)  from  so  experienced  a  breeder  as  Mr.  Tegetmeier. 
After  describing  some  cnrious  cases  in  pigeons,  of  the  transmission  of 
color  by  one  sex  alone,  and  the  formation  of  a  sub-breed  with  this 
character,  he  says:  "  It  is  a  singular  circumstance  that  Mr.  Darwin 
should  have  suggested  the  possibility  of  modifying  the  sexual  .colors 
of  birds  by  a  course  of  ari,ificial  selection.  When  he  did  so,  he  was 
in  ignorance  of  these  facts  that  1  have  related ;  but  it  is  remarkable 
how  very  closely  he  suggested  the  right  method  of  i)rocedure." 


§MtTAL  SBLEGTtdif.  ^63 

with  mankind  be  inherited  by  the  males  alone  of  one 
family,  and  in  another  family  by  the  females  alone,  though 
in  both  cases  transmitted  tlirough  the  opposite  as  well  as 
through  the  same  sex.*  Altliough  we  are  thus  ignorant, 
the  two  following  rules  seem  often  to  hold  good — that  varia- 
tions which  first  appear  in  either  sex  at  a  late  period  of  life 
tend  to  be  developed  in  the  same  sex  alone;  while  varia- 
tions which  first  appear  early  in  life  in  either  sex  tend  to 
be  developed  in  both  sexes.  I  am,  however,  far  from  sup- 
posing that  this  is  the  sole  determining  cause.  As  I  have 
not  elsewhere  discussed  this  subject,  and  as  it  has  an  impor- 
tant bearing  on  sexual  selection,  I  must  here  enter  into 
lengthy  and  somewhat  intricate  details. 

It  is  in  itself  probable  that  any  character  appearing  at  an 
early  age  would  tend  to  be  inherited  equally  by  both  sexes, 
for  the  sexes  do  not  differ  much  in  constitution  before  the 
power  of  reproduction  is  gained.  On  the  other  hand,  after 
this  power  has  been  gained  and  the  sexes  have  come  to 
differ  in  constitution,  the  gemmules  (if  I  may  again  use 
the  language  of  pangenesis)  which  are  cast  off  from  each 
varying  part  in  the  one  sex  would  be  much  more  likely  to 
possess  the  proper  affinities  for  uniting  with  the  tissues  of 
the  same  sex  and  thus  becoming  developed  than  with  those 
of  the  opposite  sex. 

I  was  first  led  to  infer  that  a  relation  of  this  kind  exists 
from  the  fact  that  whenever  and  in  whatever  manner  the 
adult  male  differs  from  the  adult  female,  he  differs  in  the 
same  manner  from  the  young  of  both  sexes.  The  generality 
of  this  fact  is  quite  remarkable;  it  holds  good  with  almost 
all  mammals,  birds,  amphibians  and  fishes;  also  with  many 
crustaceans,  spiders  and  some  few  insects,  such  as  certain 
orthoptera  and  libellulae.  In  all  these  cases  the  variations, 
through  the  accumulation  of  which  the  male  acquired  his 
proper  masculine  characters,  must  have  occurred  at  a  some- 
what late  period  of  life;  otherwise  the  young  males  would 
have  been  similarly  characterized;  and  conformably  with 
our  rule,  the  variations  are  transmitted  to  and  developed  in 
the  adult  males  alone.  When,  on  the  other  hand,  the  adult 
male  closely  resembles  the  young  of  both  sexes  (these,  with 
rare  exceptions,  being  alike),  he  generally  resembles  the 

*  References  are^iven  in  my  "  Variation  of  Animals  under  Domes- 
tication," vol.  ii,  p.  72. 


S64  THE  DESCMT  of  man. 

adult  female;  and  in  most  of  these  cases  the  variations 
through  which  the  young  and  old  acquired  their  present 
cliaracters,  probably  occurred,  according  to  our  rule,  during 
youth.  But  there  is  here  room  for  doubt,  for  characters 
are  sometimes  transferred  to  the  offspring  at  an  earlier  age 
than  that  at  which  they  first  appeared  in  the  parents,  so 
that  the  parents  may  have  varied  when  adult  and  have 
transferred  their  characters  to  their  offspring  while  young. 
There  are,  moreover,  many  animals  in  which  the  two  sexes 
closely  resemble  each  other,  and  yet  both  differ  from  their 
young;  and  here  the  characters  of  the  adults  must  have 
been  acquired  late  in  life;  nevertheless,  these  characters,  in 
apparent  contradiction  to  our  rule,  are  transferred  to  both 
sexes.  We  must  not,  however,  overlook  the  possibility  or 
even  probability  of  successive  variations  of  the  same  nature 
occurring,  under  exposure  to  similar  conditions,  simul- 
taneously in  both  sexes  at  a  rather  late  period  of  life;  and 
in  this  case  the  variations  would  be  transferred  to  the  off- 
spring of  both  sexes  at  a  corresponding  late  age;  and  there 
would  then  be  no  real  contradiction  to  the  rule  that  varia- 
tions occurring  late  in  life  are  transferred  exclusively  to  the 
sex  in  which  they  first  appeared.  This  latter  rule  seems  to 
hold  true  more  generally  than  the  second  one,  namely,  that 
variations  which  occur  in  either  sex  early  in  life  tend  to  be 
transferred  to  both  sexes.  As  it  was  obviously  impossible 
even  to  estimate  in  how  large  a  number  of  cases  throughout 
the  animal  kingdom  these  two  propositions  held  good,  it 
occurred  to  me  to  investigate  some  striking  or  crucial 
instances  and  to  rely  on  the  result. 

An  excellent  case  for  investigation  is  afforded  by  the 
deer  family.  In  all  the  species  but  one  the  horns  are 
developed  only  in  the  males,  though  certainly  transmitted 
through  the  females  and  capable  of  abnormal  development 
in  them.  In  the  reindeer,  on  the  other  hand,  the  female 
is  provided  with  horns;  so  that  in  this  species  the  horns 
ought,  according  to  our  rule,  to  appear  early  in  life,  long 
before  the  two  sexes  are  mature  and  have  come  to  differ 
much  in  constitution.  In  all  the  other  species  the  horns 
ought  to  appear  later  in  life,  which  would  lead  to  their 
development  in  that  sex  alone  in  which  they  first  appeared 
in  the  progenitor  of  the  whole  family.  Now  in  seven 
species  belonging  to  distinct  sections  of  tlie  family  and 
inhabiting  different  regions  in  which  the  stags  alone  bear 


SEXUAL  SELECTION.  2G5 

horns,  I  find  that  the  horns  first  appear  at  periods  varying 
from  nine  months  after  birth  in  the  roebuck  to  ten,  twelve 
or  even  more  months  in  the  stags  of  the  six  other  and 
larger  species.*  But  with  the  reindeer  the  case  is  widely 
different;  for,  as  I  hear  from  Prof.  Xilsson,  who  kindly 
made  special  inquiries  for  me  in  Lapland,  the  horns  appear 
in  the  young  animals  within  four  or  five  weeks  after  birth, 
and  at  the  same  time  in  both  sexes.  So  that  here  we  have 
a  structure  developed  at  a  most  unusually  early  age  in  one 
species  of  the  family  and  likewise  common  to  both  sexes  in 
this  one  species  alone. 

In  several  kinds  of  antelopes  only  the  males  are  provided 
with  horns,  while  in  the  greater  number  both  sexes  bear 
horns.  With  respect  to  the  period  of  development,  Mr. 
Blyth  informs  me  that  there  was  at  one  time  in  the  Zoo- 
logical Gardens  a  young  koodoo  {Ant.  strepsiceros)  of 
which  the  males  alone  are  horned,  and  also  the  young  of  a 
closely  allied  species,  the  eland  {Ant.  areas) ,  in  which  both 
sexes  are  horned.  N^ow  it  is  in  strict  conformity  with  our 
rule  that  in  the  young  male  koodoo,  although  t«n  months 
old,  the  horns  were  remarkably  small,  considering  the  size 
ultimately  attained  by  them;  while  in  the  young  male 
eland,  although  only  three  months  old,  the  horns  were 
already  very  much  larger  than  in  the  koodoo.  It  is  also  a 
noticeable  fact  that  in  the  prong-horned  antelope  f  only  a 
few  of  the  females,  about  one  in  five,  have  horns,  and 
these  are  in  a  rudimentary  state,  though  sometimes  above 
four  inches  long;  so  that  as  far  as  concerns  the  possession 
of  horns  by  the  males  alone,  this  species  is  in  an  inter- 
mediate condition  and  the  horns  do  not  appear  until  about 
five  or  six  months  after  birth.     Therefore  in  comparison 

*  I  am  much  obliged  to  Mr.  Cupples  for  haviug  Pi»de  inquiries  for 
me  in  regard  to  the  Roebuck  and  Red  Deer  of  Scotland  from  Mr. 
Robertson,  the  experienced  head-forest«r  to  the  MarquL*  of  Breadal- 
bane.  In  regard  to  Fallow-deer,  I  have  to  thank  Mr.  Eyton  and 
others  for  information.  For  the  Cermis  alces  of  North  America,  see 
"  Land  and  Water,"  1868,  pp.  221,  254;  and  for  the  O.  Vi^'ginianus 
and  strongyloceros  of  the  same  continent,  see  J.  D.  Caton,  in  '  Ottawa 
Acad,  of  Nat.  Sc,"  1868,  p.  13.  For  Cermis  Eldi  of  Pegu,  see  Lieut. 
Beavan,  "  Proc.  Zoolog.  Soc.,"  1867,  p.  762. 

f  Aiitilocupra  Ameiicana.  I  have  to  thank  Dr.  C'anfield  for  infor- 
mation with  respect  to  the  horns  of  the  female;  see  also  his  paper  in 
"  Pnxj.  Zoolog.  Soc."  1866,  p.  109.  Also  Owen,  '*  Anatonj  of  Verte- 
brates," vol.  iii,  p.  627. 


^(^0  THE  DESCENT  OF  MAN. 

with  what  little  we  know  of  the  development  of  the  horns 
in  other  antelopes  and  from  what  we  do  know  with  respect 
to  the  horns  of  deer,  cattle,  etc.,  those  of  the  prong-horned 
antelope  appear  at  an  intermediate  period  of  life — that  is 
not  very  early,  as  in  cattle  and  sheep,  nor  very  late,  as  in 
the  larger  deer  and  antelopes.  The  horns  of  sheep,  goats 
and  cattle  which  are  well  developed  in  both  sexes,  though 
not  quite  equal  in  size,  can  be  felt,  or  even  seen,  at  birth 
or  soon  afterward.*  Our  rule,  however,  seems  to  fail  in 
some  breeds  of  sheep,  for  instance  merinos,  in  which  the 
rams  alone  are  horned;  for  I  cannot  find  on  inquiry f  that 
the  horns  are  developed  later  in  life  in  this  breed  than  in 
ordinary  sheep  in  which  both  sexes  are  horned.  But  with 
domesticated  sheep  the  presence  or  absence  of  horns  is  not 
a  firmly  fixed  character;  for  a  certain  proportion  of  the 
merino  ewes  bear  small  horns,  and  some  of  the  rams  are 
hornless;  and  in  most  breeds  hornless  ewes  are  occasionally 
produced. 

Dr.  W.  Marshall  has  lately  made  a  special  study  of  the 
protuberances  so  common  on  the  heads  of  birds,  J;  and  he 
comes  to  the  following  conclusion:  that  with  those  species 
in  which  they  are  confined  to  the  males,  they  are  developed 
late  in  life;  whereas  with  those  species  in  which  they  are 
common  to  the  two  sexes,  they  are  developed  at  a  very 
early  period.  This  is  certainly  a  striking  confirmation  of 
my  two  laws  of  inheritance. 

In  most  of  the  species  of  the  splendid  family  of  the 
pheasants,  the  males  differ  conspicuously  from  the  females, 
and  they  acquire  their  ornaments  at  a  rather  late  period  of 

*  I  have  been  assured  that  the  horns  of  the  sheep  in  North  Wales 
can  always  be  felt,  and  are  sometimes  even  an  inch  in  length  at 
birth.  Youatt  says  ("Cattle,"  1834,  p.  377),  that  the  prominence  of 
the  frontal  bone  in  cattle  penetrates  the  cutis  at  birth,  and  that  the 
horny  matter  is  soon  formed  over  it. 

f  I  am  greatly  indebted  to  Prof.  Victor  Carus  for  having  made 
inquiries  for  me,  from  the  highest  authorities,  with  respect  to  the 
merino  sheeji  of  Saxony.  On  the  Guinea  coast  of  Africa  there  is, 
however,  a  breed  of  sheep  in  which,  as  with  merinos,  the  rams  alone 
bear  horns;  and  Mr.  Winwood  Reade  informs  me  that  in  one  case 
observed  by  him,  a  young  ram,  born  on  Feb.  10th,  first  showed  horns 
on  March  6th,  so  that  in  this  instance,  in  conformity  with  rule,  tlie 
development  of  the  horns  occurred  at  a  later  period  of  life  than  in 
Welsh  sheep,  in  which  both  sexes  are  horned. 

X  "  Ueber  die  knochermen  Schadelhocker  der  Vogel  "  in  the  "  Nie- 
derlandischen  Archiv.  fiir  Zoologie,"  Band  1,  Heft.  2,  1872. 


SBliTAL  SELfSCTTO^.  ^6t 

life.  The  eared  pheasant  (Orossoptilon  miritum),  howler, 
offers  a  remarkable  exception,  for  both  sexes  possess  the 
fine  caudal  plumes,  the  large  ear-tufts  and  the  crimson 
velvet  about  the  head;  I  find  that  all  these  characters 
appear  very  early  in  life  in  accordance  with  rule.  The 
adult  male  can,  however,  be  distinguished  from  the  adult 
female  by  the  presence  of  spurs;  and,  conformably  with 
our  rule,  "these  do  not  begin  to  be  developed  before  the  age 
of  six  months,  as  I  am  assured  by  Mr.  Bartlett,  and  even 
at  this  age  the  two  sexes  can  hardly  be  distinguished.  *  The 
male  and  female  peacock  differ  conspicuously  from  each 
other  in  almost  every  part  of  their  plumage,  excejJt  in  the 
elegant  head-crest,  which  is  common  to  both  sexes;  and  this 
is  developed  very  early  in  life,  long  before  the  other  orna- 
ments which  are  confined  to  the  male.  The  wild  duck 
offers  an  analogous  case,  for  the  beautiful  green  speculum 
on  the  wings  is  common  to  both  sexes,  though  duller  and 
somewhat  smaller  in  the  female,  and  it  is  developed  early 
in  life,  while  the  curled  tail-feathers  and  other  ornaments 
of  the  male  are  developed  later,  f  Between  such  extreme 
cases  of  close  sexual  resemblance  and  wide  dissimilarity,  as 
those  of  the  Orossoptilon  and  peacock,  many  intermediate 

*  In  the  common  peacock  (Pavo  crisiatus)  tbe  male  alone  possesses 
spurs,  while  both  sexes  of  tbe  Java  Peacock  (P.  mutieus)  offer  tbe 
unusual  case  of  being  furnished  with  spurs.  Hen<je  I  fully  expected 
that  in  tbe  latter  species  they  would  have  been  developed  earlier  in 
life  than  in  tbe  common  peaCock;  but  M.  Hegt  of  Amsterdam  informs 
me,  that  with  young  birds  of  tbe  previous  year,  of  both  species, 
compared  on  April  23,  1869,  there  was  no  difference  in  tbe  develop- 
ment of  the  spurs.  The  spurs,  however,  were  as  yet  represented 
merely  by  slight  knobs  or  elevations.  I  presume  that  I  should  have 
been  informed  if  any  difference  in  tbe  rate  of  development  had  been 
observed  subsequently, 

f  In  some  other  species  of  the  Duck  family  the  speculum  differs  in 
a  greater  degree  in  the  two  sexes;  but  I  have  not  l)een  able  to  dis- 
cover whether  its  full  development  occurs  later  in  life  in  the  males  of 
such  species,  than  in  the  males  of  tbe  common  duck,  as  ought  to  be  the 
case  according  to  our  rule.  With  the  allied  Mergus  cucullatus  we 
have,  however,  a  case  of  this  kind:  tbe  two  sexes  differ  conspicu- 
ously in  general  plumage,  and  to  a  ccmsiderable  degree  in  the  specu- 
lum, which  is  pure  white  in  tbe  male  and  grayish  white  in  the 
female.  Now  tbe  young  males  at  first  entirely  resemble  the  females, 
and  have  a  grayish- white  speculum,  which  becomes  pure  white  at  an 
earlier  age  than  that  at  which  the  adult  male  acquires  his  other  and 
more  strongly-marked  sexual  differences:  see  Audubon,  "  Ornitholo- 
gical Biography,"  vol.  iii,  1835,  i)p.  249-250. 


268  THE  DESCENT  OF  MAN. 

one^  could  be  given,  in  which  the  characters  follow  our  two 
rules  in  their  order  of  development. 

As  most  insects  emerge  from  the  pupal  state  in  a  mature 
condition  it  is  doubtful  whether  the  period  of  development 
can  determine  the  transference  of  their  characters  to  one  or 
to  both  sexes.  But  we  do  not  know  that  the  colored  scales, 
for  instance,  in  two  species  of  butterflies,  in  one  of  which 
the  sexes  differ  in  color,  while  in  the  other  they  are  alike, 
are  developed  at  the  same  relative  age  in.  the  cocoon.  Nor 
do  we  know  whether  all  the  scales  are  simultaneously  devel- 
oped on  the  wings  of  the  same  species  of  butterfly,  in 
which  certain  colored  marks  are  confined  to  one  sex,  while 
others  are  common  to  both  sexes.  A  difference  of  this  kind 
in  the  period  of  development  is  not  so  improbable  as  it  may 
at  first  appear;  for  with  the  Orthoptera,  which  assume  their 
adult  state,  not  by  a  single  metamorphosis,  but  by  a  suc- 
cession of  moults,  the  young  males  of  some  species  at  first 
resemble  the  females,  and  acquire  their  distinctive  mascu- 
line characters  only  at  a  later  moult.  Strictly  analogous 
cases  occur  at  the  successive  moults  of  certain  male 
crustaceans. 

We  have  as  yet  considered  the  transference  of  characters, 
relatively  to  their  period  of  development,  only  in  species  in 
a  natural  state;  we  will  now  turn  to  domesticated  animals, 
and  first  touch  on  monstrosities  and  diseases.  The  presence 
of  supernumerary  digits,  and  the  absence  of  certain 
phalanges,  must  be  determined  at  an  early  embryonic 
period — the  tendency  to  profuse  bleeding  is  at  least  con- 
genital, as  is  probably  color-blindness — yet  these  peculiar- 
ities, and  other  similar  ones,  are  often  limited  in  their 
transmission  to  one  sex;  so  that  the  rule  that  characters, 
developed  at  an  early  period,  tend  to  be  transmitted  to  both 
sexes,  here  wholly  fails.  But  this  rule,  as  before  remarked, 
does  not  appear  to  be  nearly  so  general  as  the  converse  one, 
namely,  that  characters  which  appear  late  in  life  in  one  sex 
are  transmitted  exclusively  to  the  same  sex.  From  the 
fact  of  the  above  abnormal  peculiarities  becoming  attached 
to  one  sex,  long  before  the  sexual  functions  are  active,  we 
may  infer  that  there  must  be  some  difference  between  the 
sexes  at  an  extremely  early  age.  With  respect  to  sexually- 
limited  diseases  we  know  too  little  of  the  period  at  which 
they  originate  to  draw  any  safe  conclusion.  Gout,  however, 
se(nns  to  fall  under  our  rule,  for  it  is  generally  caused  by 


SKXUAL  SKLEGTION.  269 

intemperance  during  manhood,  and  is  transmitted  from  the 
father  to  his  sons  in  a  much  more  marked  manner  than  to 
his  daughters. 

In  the  various  domestic  breeds  of  sheep,  goats,  and 
cattle  the  males  differ  from  their  respective  females  in 
the  shape  or  development  of  their  horns,  forehead,  mane, 
dewlap,  tail  and  hump  on  the  shoulders;  and  these  pecu- 
liarities, in  accordance  with  our  rule,  are  not  fully  devel- 
oped until  a  rather  late  period  of  life.  The  sexes  of  dogs 
do  not  differ,  except  that  in  certain  breeds,  especially  in 
the  Scotch  deer-hound,  the  male  is  much  larger  and  heavier 
than  the  female;  and,  as  we  shall  see  in  a  future  chapter, 
the  male  goes  on  increasing  in  size  to  an  unusually  late 
period  of  life,  which,  according  to  rule,  will  account  for 
his  increased  size  being  transmitted  to  his  male  offspring 
alone.  On  the  other  hand,  the  tortoise-shell  color,  which 
is  confined  to  female  cats,  is  quite  distinct  at  birth,  and 
this  case  violates  the  rule.  There  is  a  breed  of  pigeons  in 
which  the  males  alone  are  streaked  with  black,  and  the 
streaks  can  be  detected  even  in  the  nestlings;  but  they 
become  more  conspicuous  at  each  successive  moult,  so  that 
this  case  partly  opposes  and  partly  supports  the  rule.  With 
the  English  carrier  and  Pouter  pigeons,  the  full  develop- 
ment of  the  wattle  and  crop  occurs  rather  late  in  life, 
and  conformably  with  the  rule,  these  characters  are  trans- 
mitted in  full  perfection  to  the  males  alone.  The  follow- 
ing cases  perhaps  come  within  the  class  previously  alluded 
to,  in  which  both  sexes  have  varied  in  the  same  manner  at 
a  rather  late  period  of  life,  and  have  consequently  trans- 
ferred their  new  characters  to  both  sexes  at  a  corresponding 
late  period;  and  if  so,  these  cases  are  not  opposed  to  our 
rule;  there  exist  sub-breeds  of  the  pigeon,  described  by 
Neumeister,*  in  which  both  sexes  change  their  color  during 
two  or  three  moults  (as  is  likewise  the  case  with  the  Almond 
Tumbler);  nevertheless,  these  changes,  though  occurring 
rather  late  in  life,  are  common  to  both  sexes.  One  variety 
of  the  canary-bird,  namely,  the  London  Prize,  offers  a 
nearly  analogous  case. 

With  the  breeds  of  the  fowl  the  inheritance  of  various 
characters  by  one  or  both  sexes  seems  generally  determined 

*  "  Das  Ganze  der  Taubenzucht,"  1837,  ss.  21.  24.  For  the  case  of 
the  streaked  pigeons,  see  Dr.  Chapuis,  "  Le  pigeon  voyageur  Beige," 
1865,  p.  87. 


270  THE  DESCENT  OF  MAN. 

by  the  period  at  wliicli  such  cliamcters  are  developed.  Thus 
in  all  the  many  breeds  in  which  the  adult  male  differs 
greatly  in  color  from  the  female,  as  well  as  from  tlie  wild 
parent-species,  he  differs  also  from  the  young  male,  so  that 
the  newly-acquired  characters  must  have  appeared  {it  a 
rather  late  period  of  life.  On  tlie  other  hand,  in  most  of 
the  breeds  in  which  the  two  sexes  resemble  each  other,  the 
young  are  colored  in  nearly  tlie  same  manner  as  their 
parents,  and  this  renders  it  probable  that  their  colors  first 
ap})eared  early  in  life.  We  have  instances  of  this  fact  in 
all  black  and  white  breeds,  in  which  the  young  and  old  of 
both  sexes  are  alike;  nor  can  it  be  maintained  that  there  is 
soinetliing  peculiar  in  a  black  or  white  plumage,  which 
leads  to  its  transference  to  both  sexes;  for  the  males  alone 
of  many  natural  species  are  either  black  or  white,  the 
feiaales  being  differently  colored.  With  the  so-called 
Cuckoo  sub-breeds  of  the  fowl  in  which  the  feathers  are 
transversely  penciled  with  dark  stripes,  both  sexes  and  the 
chickens  are  colored  in  nearly  the  same  manner.  The 
lacod  plumage  of  the  Sebright  bantam  is  the  same  in  both 
sexes,  and  in  the  young  chickens  the  wing-feathers  are  dis- 
tinctly, though  imperfectly,  laced.  Spangled  Ilamburgs, 
however,  offer  a  partial  exception ;  for  the  two  sexes, 
though  not  quite  alike,  resemble  each  other  more  closely 
than  do  the  sexes  of  the  aboriginal  parent-species;  yet  they 
acquire  their  characteristic  plumage  late  in  life,  for  the 
chickens  are  distinctly  penciled.  With  respect  to  other 
characters  besides  color,  in  the  wild-parent  species  and  in 
most  of  the  domestic  breeds  the  males  alone  possess  a  well- 
leveloped  comb;  but  in  the  young  of  the  Spanish  fowl  it 
is  largely  developed  at  a  very  early  age,  and,  in  accordance 
with  this  early  development  in  the  male,  it  is  of  unusual 
size  in  the  adult  female.  In  the  game  breeds  pugnacity  is 
developed  at  a  wonderfully  early  age,  of  which  curious 
proofs  could  be  given;  and  this  character  is  transmitted  to 
both  sexes,  so  that  the  hens,  from  their  extreme  pugnacity, 
are  now  generally  exhibited  in  separate  pens.  With  the 
Polish  breeds  the  bony  protuberance  of  the  skull  which 
supports  the  crest  is  partially  developed  even  before  the 
chickens  are  hatched,  and  the  crest  itself  soon  begins  to 
grow,  though  at  first  feebly;*  and  in  this  breed  the  adults 

*For  full  particulars  and  references  on  all  these  points  respecting- 
the  severa.  breeds  of  the  fowl,  see  "  Variation  of  Animals  and  Plants 


SEXUAL  SELECTION.  2 71 

of  both  sexes  are  characterized  by  a  great  bony  protuber- 
ance and  an  immense  crest. 

Finally,  from  what  we  have  now  seen  of  the  relation 
which  exists  in  many  natural  species  and  domesticated 
races  between  the  period  of  the  development  of  their  char- 
acters and  the  manner  of  their  transmission — for  example, 
the  striking  fact  of  the  early  growth  of  the  horns  in  the 
reindeer,  in  which  both  sexes  bear  horns,  in  comparison 
with  their  much  later  growth  in  the  other  species  in  which 
the  male  alone  bears  horns — we  may  conclude  that  one, 
though  not  the  sole  cause  of  characters  being  exclusively 
inherited  by  one  sex,  is  their  development  at  a  late  age. 
And  secondly,  that  one,  though  apparently  a  less  effective 
cause  of  characters  being  inherited  by  both  sexes,  is  their 
development  at  an  early  age,  while  the  sexes  differ  but 
little  in  constitution.  It  appears,  however,  that  some  dif- 
ference must  exist  between  the  sexes  even  during  a  very 
early  embryonic  period,  for  characters  developed  at  this 
age  not  rarely  become  attached  to  one  sex. 

Summary  and  Concluding  Remarks. — From  the  forego- 
ing discussion  on  the  various  laws  of  inheritance  we  learn 
that  the  characters  of  the  parents  often,  or  even  generally, 
tend  to  become  developed  in  the  offspring  of  the  same  sex, 
at  the  same  age,  and  periodically  at  the  same  season  of  the 
year  in  Avhicli  they  first  appeared  in  the  parents.  But 
these  rules,  owing  to  unknown  causes,  are  far  from  being 
fixed.  Hence,  during  the  modification  of  a  species  the 
successive  changes  may  readily  be  transmitted  in  different 
ways;  some  to  one  sex  and  some  to  both;  some  to  the  off- 
spring at  one  age  and  some  to  the  offspring  at  all  ages. 
Not  only  are  the  laws  of  inheritance  extremely  complex, 
but  so  are  the  causes  which  induce  and  govern  variability. 
The  variations  thus  induced  are  preserved  and  accumulated 
by  sexual  selection,  which  is  in  itself  an  extremely  complex 
affair,  depending  as  it  does  on  the  ardor  of  love,  the  cour- 
age and  the  rivalry  of  the  males  as  well  as  on  the  powers 
of  perception,  the  taste  and  will  of  the  female.  Sexual 
selection  will  also  be  largely  dominated  by  natural  selection 

under  Domestication,"  vol.  i,  pp.  250,  256.  In  regard  to  the  higher 
animals,  the  sexual  differences  which  liave  arisen  under  domestica- 
tion are  described  in  the  same  work  under  the  head  of  each  species. 


272  THE  DESCENT  OF  MAN 

tending  toward  the  general  welfare  of  the  species.  Hence 
the  manner  in  which  the  individuals  of  either  oi'  both 
sexes  have  been  affected  through  sexual  selection  cannot 
fail  to  be  complex  in  the  highest  degree. 

When  variations  occur  late  in  life  in  one  sex  and  are 
transmitted  to  the  same  sex  at  the  same  age  the  other  sex 
and  the  young  are  left  unmodified.  When  they  occur  late 
in  life  but  are  transmitted  to  botli  sexes  at  the  same  age 
the  young  alone  are  left  unmodified.  Variations,  however, 
may  occur  at  any  period  of  life  in  one  sex  or  in  both,  and 
be  transmitted  to  both  sexes  at  all  ages,  and  then  all  the 
individuals  of  the  species  are  similarly  modified.  In  the 
following  chapters  it  will  be  seen  that  all  these  cases  fre- 
quently occur  in  nature. 

Sexual  selection  can  never  act  on  any  animal  before  the 
age  for  reproduction  arrives.  From  the  great  eagerness  of 
the  male  it  has  generally  acted  on  this  sex  and  not  on  the 
females.  The  males  have  thus  become  provided  with 
weapons  for  fighting  with  their  rivals,  with  organs  for  dis- 
covering and  securely  holding  the  female  and  for  exciting 
or  charming  her.  When  the  sexes  differ  in  these  respects 
it  is  also,  as  we  have  seen,  an  extremely  general  law  that 
the  adult  male  differs  more  or  less  from  the  young  male; 
and  we  may  conclude  from  this  fact  that  the  successive 
variations  by  which  the  adult  male  became  modified  did 
not  generally  occur  much-before  the  age  for  reproduction. 
Whenever  some  or  many  of  the  variations  occurred  early  in 
life  the  young  males  would  partake  more  or  less  of  the 
characters  of  the  adult  males;  and  differences:  of  this  kind 
between  the  old  and  young  males  may  be  observed  in  many 
species  of  animals. 

It  is  probable  that  young  male  animals  have  often  tended 
to  vary  in  a  manner  which  would  not  only  have  been  of  no 
use  to  them  at  an  early  age,  but  would  have  been  actually 
injurious  —  as  by  acquiring  bright  colors  which  would 
render  them  conspicuous  to  their  enemies,  or  by  acquiring 
structures,  such  as  great  horns,  which  would  expend  much 
vital  force  in  their  development.  Variations  of  this  kind 
occurring  in  the  young  males  would  almost  certainly  be 
eliminated  through  natural  selection.  With  the  adult  and 
experienced  males,  on  the  other  hand,  the  advantages 
derived  from  the  acquisition  of  such  characters  would 
more  than  counterbalance  some  exposure  to  danger  and 
some  loss  of  vital  force. 


SEXUAL  SELECTION.  273 

As  variations  which  give  to  the  male  a  better  cliance  of 
conquering  other  males  or  of  finding,  securing  or  charm- 
ing the  opposite  sex  would,  if  they  happened  to  arise  in  the 
female,  be  of  no  service  to  her,  they  would  not  be  pre- 
served in  her  through  sexual  selection.  We  have  also  good 
evidence  with  domesticated  animals  that  variations  of  all 
kinds  are,  if  not  carefully  selected,  soon  lost  through  inter- 
crossing and  accidental  deaths.  Consequently  in  a  state 
of  nature  if  variations  of  the  above  kind  chanced  to  arise 
in  the  female  line,  and  to  be  transmitted  exclusively  in 
this  line,  they  would  be  extremely  liable  to  be  lost.  If, 
however,  the  females  varied  and  transmitted  their  newly 
acquired  characters  to  their  offspring  of  both  sexes  the 
characters  which  were  advantageous  to  the  males  would  be 
preserved  by  them  through  sexual  selection,  and  the  two 
sexes  would  in  consequence  be  modified  in  the  same  man- 
ner, although  such  characters  were  of  no  use  to  the 
females;  but  I  shall  hereafter  have  to  recur  to  these  more 
intricate  contingencies.  Lastly,  the  females  may  acquire 
and  apparently  have  often  acquired  by  transference  char- 
acters from  the  male  sex. 

As  variations  occurring  late  in  life  and  transmitted  to 
one  sex  alone  have  incessantly  been  taken  advantage  of  and 
accumulated  through  sexual  selection  in  relation  to  the 
reproduction  of  the  species;  therefore  it  appears,  at  first 
sight,  an  unaccountable  fact  that  similar  variations  have 
not  frequently  been  accumulated  through  natural  selection, 
in  relation  to  the  ordinary  habits  of  life.  If  this  had 
occurred,  the  two  sexes  would  often  have  been  differently 
modified,  for  the  sake,  for  instance,  of  capturing  prey  or 
of  escaping  from  danger.  Differences  of  this  kind  between 
the  two  sexes  do  occasionally  occur,  especially  in  the  lower 
classes.  But  this  implies  that  the  two  sexes  follow  different 
habits  in  their  struggles  for  existence,  which  is  a  rare  cir- 
cumstance with  the  higher  animals.  The  case,  however,  is 
widely  different  with  the  reproductive  functions,  in  which 
respect  the  sexes  necessarily  differ.  For  variations  in 
structure,  which  are  related  to  these  functions,  have  often 
proved  of  value  to  one  sex,  and  from  having  arisen  at  a  late 
period  of  life,  have  been  transmitted  to  one  sex  alone;  and 
such  variations,  thus  preserved  and  transmitted,  have  given 
rise  to  secondary  sexual  characters. 

In  the  following  chapters  1  shall  treat  of  the  secondary 


274  THE  DESCENT  OF  MAN. 

sexual  characters  in  animals  of  all  classes,  and  shall 
endeavor  in  each  case  to  apply  the  principles  explained  in 
the  present  chapter.  The  lowest  classes  will  detain  us  for 
a  very  short  time,  but  the  higher  animals,  especially  birds, 
must  be  treated  at  considerate  length.  It  should  be  borne 
in  mind  that  for  reasons  already  assigned  I  intend  to  give 
only  a  few  illustrative  instances  of  the  innumerable 
structures  by  the  aid  of  which  the  male  finds  the  female, 
or,  when  found,  holds  her.  On  the  other  hand,  all 
structures  and  instincts  by  the  aid  of  which  the  male  con- 
quers other  males,  and  by  which  he  allures  or  excites  the 
female,  will  be  fully  discussed,  as  these  are  in  many  ways 
the  most  interesting. 

SUPPLEMENT    ON   THE    PROPORTIONAL     NUMBERS    OF   THE 
TWO.  SEXES     IN     ANIMALS     BELONGING    TO     VARIOUS 

CLASSES. 

As  no  one,  as  far  as  I  can  discover,  has  paid  attention  to 
the  relative  numbers  of  the  two  sexes  throughout  the 
animal  kingdom,  I  will  here  give  such  materials  as  I  have 
been  able  to  collect,  although  they  are  extremely  imperfect. 
They  consist  in  only  a  few  instances  of  actual  enumeration 
and  the  numbers  are  not  very  large.  As  the  proportions 
are  known  with  certainty  only  in  mankind,  1  will  first  give 
them  as  a  standard  of  comparison. 

Man. — In  England  during  ten  years  (from  1857  to  1866) 
the  average  number  of  children  born  alive  yearly  was 
707,1!;J0,  in  the  proportion  of  104.5  males  to  100  females. 
VfWl  in  1857  the  male  births  throughout  England  were  as 
105.^,  and  in  1865  as  104  to  100.  Looking  to  separate 
districts,  in  Buckinghamshire  (where  about  5,000  children 
are  annually  born)  the  mean  proportion  of  male  to  female 
births  during  the  whole  period  of  the  above  ten  years  was 
as  102.8  to  100,  while  in  N.  Wales  (where  the  average 
annual  births  are  12,873)  it  was  as  high  as  106.2  to  100. 
Taking  a  still  smaller  district,  viz.,  Rutlandshire  (where 
the  annual  births  average  only  739),  in  1864  the  male 
births  were  as  114.6,  and  in  1862  as  only  97  to  100;  but 
even  in  this  small  district  the  average  of  the  7,385  births 
.during   the  whole   ten   years  was   as   104.5  to  100  ;  that 


PROPORTION  OF  THE  SEXES.  275 

is  in  the  same  ratio  as  throughout  England.*  The  propor- 
tions are  sometimes  slightly  disturbed  by  unknown  causes; 
thus  Prof.  Faye  states  '^  that  in  some  districts  of  Norway 
there  has  been  during  a  decennial  period  a  steady  deficiency 
of  boys,  while  in  others  the  opposite  condition  has  existed." 
In  France,  during  forty-four  years,  the  male  to  the  female 
births  have  been  as  106.2  to  100;  but  during  this  period  it 
has  occurred  five  times  in  one  department  and  six  times 
in  anotlier,  that  the  female  births  have  exceeded  the  males. 
In  Russia  the  average  proportion  is  as  high  as  108.9,  and 
in  Philadelphia,  in  the  United  States,  as  110.5  to  100. f  The 
average  for  Europe,  deduced  by  Bickes  from  about  70,000,- 
000  births,  is  106  males  to  100  females.  On  the  other 
hand,  with  white  children  born  at  the  Cape  of  Good  Hope, 
the  proportion  of  males  is  so  low  as  to  fluctuate  during  suc- 
cessive years  between  90  and  99  males  for  every  100  females. 
It  is  a  singular  fact  that  with  Jews  the  proportion  of  male 
births  is  decidedly  larger  than  with  Christians ;  thus  in 
Prussia  the  proportion  is  as  113,  in  Breslau  as  114,  and  in 
Livonia  as  120  to  100;  the  Christrian  births  in  these  coun- 
tries being  the  same  as  usual,  for  instancy,  in  Livonia  as 
104  to  100.  t 

Prof.  Faye  remarks  that  "  a  still  greater  preponderance 
of  males  would  be  met  with,  if  death  struck  both  sexes  in 
equal  porportion  in  the  womb  and  during  birth.  But  tlie 
fact  is,  that  for  every  100  still-born  females  we  have  in 
seveml  countries  from  134.6  to  144.9  still-born  males. 
During  the  first  four  or  five  years  of  life,  also,  more  male 
children  die  than  females,  for  example  in  England,  during 
the  first  year,  126  boys  die  for  every  100  girls — a  proportion 
which  in  France  is  still  more  unfavorable. '''§     Dr.  Stock- 

*"  Twenty-ninth  Annual  Report  of  the  Ragistrar-Oeneral  for 
1866."     In  this  report  (p.  12)  a  special  decennial  table  is  given. 

f  For  Norway  and  Russia,  see  abstract  of  Prof.  Fare's  researches 
in  "  British  and  Foreign  Medico-Chirurg.  Review,"  April,  1867,  pp. 
343,345.  For  France,  the  "  Annuaire  pour  I'An,  1867,"  p.  213. 
For  Philadelphia,  Dr.  Stockton  Hough.  *' Social  Science  Assoc.," 
1874.  For  the  Cape  of  Good  Hope,  Quetelet  as  quoted  by  Dr.  H.  H. 
Zouteveen  in  the  Dutch  translation  of  this  work  (vol.  i,  p.  417),  where 
much  information  is  given  on  the  proportion  of  the  sexes. 

:j:In  regard  to  the  Jews,  see  M.  Thury,  "  La  Loi  de  Production  des 
Sexes,"  1863,  p.  25. 

§"  British  and  Foreign  Medico-Chirurg.  Review,"  April,  1867,  p. 
343.     Dr.  Stark  also   remarks  ("  Tenth   Annual   Report  of  Births, 


276  ^^^  DESCENT  OF  MAN. 

ton  Hough  accounts  for  these  facts  in  part  by  the  more 
frequent  defective  development  of  males  tlian  of  females. 
We  have  before  seen  that  the  male  sex  is  more  variable  in 
structure  than  the  female  ;  and  variations  in  important 
organs  would  generally  be  injurious.  But  the  size  of  the 
body,  and  especially  of  the  head,  being  greater  in  male 
than  female  infants  is  another  cause;  for  the  males  are  thus 
more  liable  to  be  injured  during  parturition.  Consequently 
the  still-born  males  are  more  numerous;  and  as  a  highly 
competent  judge.  Dr.  C  rich  ton  Browne,*  believes,  male 
infants  often  suffer  in  health  for  some  years  after  birth. 
Owing  to  this  excess  in  the  death-rate  of  male  children, 
both  at  birth  and  for  some  time  subsequently,  and  owing  to 
the  exposure  of  grown  men  to  various  dangers  and  to  their 
tendency  to  emigrate,  the  females  in  all  old-settled  coun- 
tries, where  statistical  records  have  been  kept,f  are  found 
to  preponderate  considerably  over  the  males. 

It  seems  at  first  sight  a  mysterious  fact  that  in  different 
nations,  under  different  conditions  and  climates,  in  Naples, 
Prussia,  Westphalia,  Holland,  France,  England  and  the 
United  States,  the  excess  of  male  over  female  births  is  less 
when  they  are  illegitimate  than  when  legitimate.;]:  This 
has  been  explained  by  different  writers  in  many  different 
ways,  as  from  the  mothers  being  generally  young,  from  the 
large   proportion  of   first  pregnancies,  etc.     But  we   have 

Deaths,  etc.,  in  Scotland,"  1867,  p.  28)  tliat  "These  examples  may 
suffice  to  show  that,  at  almost  every  stage  of  life,  the  males  in  Scot- 
land have  a  greater  liability  to  death  and  a  higher  death-rate  than 
the  females.  The  fact,  however,  of  this  peculiarity  being  most 
strongly  developed  at  that  infantile  period  of  life  when  the  dress, 
food  and  general  treatment  of  both  sexes  are  alike,  seems  to  prove 
that  the  higher  male  death-rate  is  an  impressed,  natural  and  consti- 
tutional peculiarity  due  to  sex  alone." 

*  •'  West  Riding  Lunatic  Asylum  Reports."  vol.  i,  1871,  p.  8.  Sir 
J,  Simpson  has  proved  that  the  head  of  the  male  infant  exceeds  that 
of  the  female  by  three-eighths  of  an  inch  in  circumference  and  by 
one  eighth  in  transverse  diameter.  Quetelet  has  shown  that  woman 
is  born  smaller  than  man  ;  see  Dr.  Duncan,  "  Fecundity,  Fertility, 
Sterility,"  1871,  p.  382. 

f  With  the  savage  Guaranys  of  Paraguay,  according  to  the  accu- 
rate Azara  ("  Voyages  dans  I'Amerique  merid.,"  tom.  ii,  1809,  pp.  60, 
179)  the  women  are  to  the  men  in  the  porportion  of  14  to  13. 

:}:  Babbage,  "Edinburgh  Journal  of  Science,"  1829,  vol.  i,  p.  88; 
also  p.  90,  on  still-born  children.  On  illegitimate  children  in  En- 
gland, see  "  Report  of  Registrar -General  for  1866,"  p.  15. 


pROPokrioN  OF  mi:  sexes.  277 

seen  that  male  infants,  from  the  large  size  of  their  heads, 
suffer  more  than  female  infants  during  parturition;  and  as 
the  mothers  of  illegitimate  children  must  be  more  liable 
than  other  women  to  undergo  bad  labors,  from  various 
causes,  such  as  attempts  at  concealment  by  tight  lacing, 
hard  work,  distress  of  mind,  etc.,  their  male  infants  would 
proportionately  suffer.  And  this  probably  is  the  most  effi- 
cient of  all  the  causes  of  the  porportion  of  males  to  females 
bom  alive  being  less  among  illegitimate  children  than 
among  the  legitimate.  With  most  animals  the  greater  size 
of  the  adult  male  than  of  the  female,  is  due  to  the  stronger 
males  having  conquered  the  weaker  in  their  struggles  for 
the  possession  of  the  females,  and  no  doubt  it  is  owing  to 
this  fact  that  the  two  sexes  of  at  least  some  animals  differ 
in  size  at  birth.  Thus  we  have  the  curious  fact  that  we 
may  attribute  the  more  frequent  deaths  of  male  than 
female  infants,  especially  among  the  illegitimate,  at  least 
in  part  to  sexual  selection. 

It  has  often  been  supposed  that  the  relative  age  of  the 
two  parents  determines  the  sex  of  the  offspring;  and  Prof. 
Leuckart  *  has  advanced  what  he  considers  sufficient  evi- 
dence, with  respect  to  man  and  certain  domesticated 
animals,  that  this  is  one  important  though  not  the  sole 
factor  in  the  result.  So  again  the  period  of  impregnation 
relatively  to  the  state  of  the  female  has  been  thought  by 
some  to  be  the  efficient  cause;  but  recent  observations  dis- 
countenance this  belief.  According  to  Dr.  Stockton 
Hough,  t  the  season  of  the  year,  the  poverty  or  wealth  of 
the  parents,  residence  in  the  country  or  in  cities,  the  cross- 
ing of  foreign  immigrants,  etc.,  all  influence  the  proportion 
of  the  sexes.  With  mankind,  polygamy  has  also  been  sup- 
posed to  lead  to  the  birth  of  a  greater  proportion  of  female 
infants;  but  Dr.  J.  Campbell  J  carefully  attended  to  this 
subject  in  the  harems  of  Siam,  and  concludes  that  the  pro- 
portion of  male  to  female  births  is  the  same  as  from 
monogamous  unions.  Hardly  any  animal  has  been  rendered 
so  highly  polygamous  as  the  English  race-horse,  and  we 
shall  immediately  see  that  his  male  and  female  offspring 

*  Leuckart,  in  Wagner,  "  Handworterbuch  der  Phys.,"  B.  iv,  1853, 
s.  774. 

f  Social  Science  Assoc,  of  Philadelphia,  1874. 
J"  Anthropological  Review,"  April,  1870,  p.  108. 


278  '^'H^  l)t:8GENT  OF  MAN, 

are  almost  exactly  equal  in  number.  I  will  tidW  give  tlie 
facts  which  I  have  collected  with  respect  to  the  proportional 
numbers  of  the  sexes  of  various  animals;  and  will  then 
briefly  discuss  how  far  selection  has  come  into  play  in 
determining  the  result. 

Horses. — Mr.  Tegetiaeier  has  been  so  kind  as  to  tabulate  for  me 
from  the  "Racing  Calendar"  the  births  of  race-horses  during  a 
period  of  twenty-one  years,  viz.,  from  1846  to  1867;  1849  being 
omitted,  as  no  returns  were  that  year  published.  The  total  births 
were  25,560,*  consisting  of  12,763  males  and  12,797  females,  or  in  the 
proportion  of  99.7  males  to  100  females.  As  these  numbers  are  tol- 
erably large,  and  as  they  are  drawn  from  all  parts  of  England,  dur- 
ing several  years,  we  may  with  much  confidence  conclude  that  with 
the  domestic  horse,  or  at  least  with  the  race-horse,  the  two  sexes  are 
produced  in  almost  equal  numbers.  The  fluctuations  in  the  propor- 
tions during  successive  years  are  closely  like  those  which  occur  with 
mankind,  when  a  small  and  thinly  populated  area  is  considered;  thus 
in  1856  the  male  horses  were  as  107.1,  and  in  1867  as  only  92.6  to 
100  females.  In  the  tabulated  returns  the  proportions  vary  in  cycles, 
for  the  males  exceeded  the  females  during  six  successive  years;  and 
the  females  exceeded  the  males  during  two  periods  each  of  four 
years;  this,  however,  may  be  accidental;  at  least  I  can  detect  nothing 
of  the  kind  with  man  in  the  decennial  table  in  the  Registrar's  Report 
for  1866. 

Dogs. — During  a  period  of  twelve  years,  from  1857  to  1868,  the 
births  of  a  large  number  of  greyhounds  throughout  England  were 
sent  to  the  "Field"  newspaper;  and  I  am  again  indebted  to  Mr. 
Tegetmeier  for  carefully  tabulating  the  results.  The  recorded  births 
were  6,878,  consisting  of  3,605  males  and  3,273  females,  that  is,  in 
the  proportion  of  1 10. 1  males  to  100  females.  The  greatest  fluctua- 
tions occurred  in  1864,  when  the  proportion  was  as  95.3  males,  and 
in  1867,  as  116.3  males  to  100  females.  The  above  average  propor- 
tion of  110.1  to  100  is  probably  nearly  correct  in  the  case  of  the  grey- 
hound, but  whether  it  would  hold  with  other  domesticated  breeds  is 
in  some  degree  doubtful.  Mr.  Cupples  has  inquired  from  several 
great  breeders  of  dogs,  and  finds  that  all  without  exception  believe 
that  females  are  produced  in  excess;  but  he  suggests  that  this  belief 
may  have  arisen  from  females  being  less  valued,  and  from  the 
consequent  disappointment  producing  a  stronger  impression  on  the 
mind. 

Sheep. — The  sexes  of  sheep  are  not  ascertained  by  agriculturists 
until  several  months  after  birth,  at  the  period  when  the  males  are 

*  During  eleven  years  a  record  was  kept  of  the  number  of  mares  which 
proved  ban-en  or  prematurely  slipped  their  foals  ;  and  it  deserves  notice,  as 
showinj?  how  infertile  these  highly  nurtured  and  rather  closely  interbred  ani- 
mals have  become,  that  not  far  from  one-third  of  the  mares  failed  to  produce 
living  foals.  Thus  during  1860,  809  male  eolts  and  816  female  colts  were  born, 
and  74:^  mares  failed  to  produce  offspring.  During  1867,  836  males  and  902 
females  were  born,  and  794  mares  failed. 


PROPORTION  OF  THB  SEXES.  ^•^'O 

castrated;  so  that  the  following  returns  do  not  give  the  proportions 
at  birth.  Moreover,  I  find  that  several  great  breeders  in  Scotland, 
who  annually  raise  some  thousand  sheep,  are  firmly  convinced  that 
a  larger  proportion  of  males  than  of  females  die  during  the  first  year 
or  two.  Therefore  the  proportion  of  males  would  be  somewhat  larger 
at  birth  than  at  the  age  of  castration.  This  is  a  remarkable  coinci- 
dence with  what,  as  we  have  seen,  occurs  with  mankind,  and  both 
cases  probably  depend  on  the  same  cause.  I  have  received  returns 
from  four  gentlemen  in  England  who  have  bred  Lowland  sheep, 
chiefly  Leicesters,  during  the  last  ten  to  sixteen  years;  they  amount 
altogether  to  8,965  births,  consisting  of  4,407  males  and  4,558  females; 
that  is  in  the  proportion  of  96.7  males  to  100  females.  With  respect 
to  Cheviot  and  black-faced  sheep  bred  in  Scotland,  I  have  received 
returns  from  six  breeders,  two  of  them  on  a  large  scale,  chiefly  for 
the  years  1867-1869,  but  some  of  the  returns  extend  back  to  1862. 
The  total  number  recorded  amounts  to  50,685,  consisting  of  25,071 
males  and  25,614  females,  or  in  the  proportion  of  97.9  males  to  100 
females.  If  we  take  the  English  and  Scotch  returns  together,  the 
total  number  amounts  to  59,650,  consisting  of  29,478  males  and  30,172 
females,  or  as  97.7  to  100.  So  that  with  sheep  at  the  age  of  castra- 
tion the  females  are  certainly  in  excess  of  the  males,  but  probably 
this  would  not  hold  good  at  birth.* 

CatUe. — I  have  received  returns  from  nine  gentlemen  of  982  births, 
too  few  to  be  trusted  ;  these  consisted  of  477  bull-calves  and  505 
cow-calves;  *.  e.,  in  the  proix)rtion  of  94.4  males  to  100  females. 
The  Rev.  W.  D.  Fox  informs  me  that  in  1867  out  of  34  calves  born 
on  a  farm  in  Derbyshire  only  one  was  a  bull.  Mr.  Harrison  Weir 
has  inquired  from  several  breeders  of  pigs,  and  most  of  them  esti- 
mate the  male  to  the  female  births  as  about  7  to  6.  This  same 
gentleman  has  bred  rabbits  for  many  years,  and  has  noticed  that  a 
far  greater  number  of  bucks  are  produced  than  does.  But  estima- 
tions are  of  little  value. 

Of  mammalia  in  a  state  of  nature  I  have  been  able  to  learn  very 
little.  In  regard  to  the  common  rat,  I  have  received  conflicting 
statements.  Mr.  R.  Elliot,  of  Laighwood,  informs  me  that  a  rat- 
catcher assured  him  that  he  had  always  found  the  males  in  great 
excess,  even  with  the  young  in  the  nest.  In  consequence  of  this, 
Mr.  Elliot  himself  subsequently  examined  some  hundred  old  ones 
and  found  the  statement  true.  Mr.  F.  Buckland  has  bred  a  large 
number  of  white  rats,  and  he  also  believes  that  the  males  greatly 
exceed  the  females.  In  regard  to  moles,  it  is  said  that  "  the  males 
are  much  more  numerous  than  the  females  ;"  f  and  as  the  catching 
of  these  animals  is  a  special  occupation,  the  statement  may  perhaps 
be  trusted.     Sir  A.  Smith,  in  describing  an  antelope  of  S.   Af  ricaj 

*  I  ara  much  indebted  to  Mr.  Cupples  for  having  procured  for  me  the  above 
returns  from  Scotland,  as  well  as  some  of  the  foUowine:  returns  on  cattle.  Mr. 
R.  Elliot,  of  Laighwoo<l,  fii-st  called  my  attention  to  the  premature  deaths  of 
the  males— a  statement  subsequently  confirmed  by  Mr.  Aitchison  and  others. 
To  tliis  latter  gentleman,  and  to  Mr.  Payan,  1  owe  my  thanks  for  large  returns 
as  to  sheep. 

t  Bell,  ."  History  of  British  Quadrupeds,"  p.  100. 

X  "  Illustrations  of  the  Zoology  of  S.  Africa,"  1849,  pi,  29. 


280  THE  DESCENT  OF  MAN. 

{Kobus  ellipsiprymnus),  remarks,  that  in  the  herds  of  this  and  othei, 
species,  the  males  are  few  in  number  compared  with  the  females  ; 
the  natives  believe  that  they  are  born  in  this  proportion;  others 
believe  that  the  younger  males  are  expelled  from  the  herds,  and  Sir 
A.  Smith,  says,  that  though  he  has  himself  never  seen  herds  con- 
sisting of  young  males  alone,  others  affirm  that  this  does  occur.  It 
appears  probable  that  the  young  when  expelled  from  the  herd  would 
often  fall  a  prey  to  the  many  beasts  of  prey  of  the  country. 

Birds. — With  respect  to  the  fowl,  I  have  received  only  one 
account,  namely,  that  out  of  1,001  chickens  of  a  highly-bred  stock  of 
Cochins,  reared  during  eight  years  by  Mr.  Stretch,  487  proved  males 
and  514  females;  i.  e.,  as  94.7  to  100.  In  regard  to  domestic  pigeons 
there  is  good  evidence  either  that  the  males  are  produced  in  excess, 
or  that  tbey  live  longer  ;  for  these  birds  invariably  pair,  and  single 
males,  as  Mr.  Tegetmeier  informs  me,  can  always  be  purchased 
cheaper  than  females.  Usually  the  two  birds  reared  from  the  two 
eggs  laid  in  the  same  nest  are  a  male  and  a  female;  but  Mr.  Harrison 
Weir,  who  has  been  so  large  a  breeder,  says  that  he  has  often  bred 
two  cocks  from  the  same  nest,  and  seldom  two  hens  ;  moreover,  the 
hen  is  generally  the  weaker  of  the  two  and  more  liable  to  perish. 

With  respect  to  birds  in  a  state  of  nature,  Mr.  Gould  and  others  * 
are  convinced  that  the  males  are  generally  the  more  numerous  ;  and 
as  the  young  males  of  many  species  resemble  the  females,  the  latter 
would  naturally  appear  to  be  the  more  numerous.  Large  numbers 
of  pheasants  are  reared  by  Mr.  Baker  of  Ijeadenhall  from  eggs  laid 
by  wild  birds,  and  he  informs  Mr.  Jenner  Weir  that  four  or  five 
males  to  one  female  are  generally  produced.  An  experienced 
observer  remarks, f  that  in  Scandinavia  the  broods  of  the  capercailzie 
and  black-cock  contain  more  males  than  females  :  and  that  with  the 
Dal  ripa  (a  kind  of  ptarmigan)  more  males  than  females  attend  the 
leks  or  places  of  courtship  ;  but  this  latter  circumstance  is  accounted 
for  by  some  observers  by  a  greater  number  of  hen  birds  being 
killed  by  vermin.  From  various  facts  given  by  White  of  Selborne,:}: 
it  seems  clear  that  the  males  of  the  partridge  must  be  in  considerable 
excess  in  the  south  of  England  ;  and  1  have  been  assured  that  this  is 
the  case  in  Scotland.  Mr.  Weir  on  inquiring  from  the  dealers  who 
receive  at  certain  seasons  large  numbers  of  ruflfs  (Machetes  pugnax), 
was  told  that  the  males  are  much  the  more  numerous.  This  same 
naturalist  has  also  inquired  for  me  from  the  bird-catchers,  who  annu- 
ally catch  an  astonishing  number  of  various  small  species  alive  for 
the  London  market,  and  he  was  unhesitatingly  answered  by  an 
old  and  trustworthy  man,  that  with  the  chaffinch  the  males 
are  in  large  excess  ;  he  thought  as  high  as  2  males 
to   1    female,     or    at     least     as     high     as    5   to  3.  §     The    males 

*  Brehm  ("  Illust  Thierleben,"  B.  iv.  s.  990)  comes  to  the  same  conclusion. 

t  On  the  authority  of  L.  Lloyd,  "  Game  Birds  of  Sweden,"  1867,  pp.  12, 132. 

t"Nat.  Hist,  of  Selborne,"  letter  xxix.  edit,  of  1825,  vol.  i,  p.  139. 

§Mr.  Jenner  Weir  received  similar  information,  on  making:  inquiries 
during?  the  followinj?  year.  To  show  the  number  of  livlnj;  ehsiflfinches  caught 
I  may  mention  that  in  1869  there  was  a  match  between  two  expert*?,,  and  one 
man  caught  in  a  day  62,  and  another  40,  male  chaffinches.  The  greatest  num- 
ber ever  caught  by  one  man  in  a  single  day  was  70. 


PROPORTION  OF  THE  SEXES.  ^81 

of  the  blackbird,  he  likewise  maintained,  were  bv  far  the  more 
numerous,  whether  caught  by  traps  or  by  netting  at  night.  These 
statements  may  apparently  be  trusted,  because  this  same  man  said 
that  the  sexes  are  about  equal  with  the  lark,  the  twite  {^Linaria 
montana),  and  goldfinch.  On  the  other  hand,  he  is  certain  that  with 
the  common  linnet,  the  females  preponderate  greatly,  but  unequally, 
during  different  years;  during  some  years  he  has  found  the  females 
to  the  males  as  4  to  1.  It  should,  however,  be  borne  in  mind, 
that  the  chief  season  for  catching  birds  does  not  begin  till  September, 
so  that  with  some  species  partial  migrations  may  have  begun,  and 
the  flocks  at  this  period  often  consist  of  hens  alone.  Mr.  Salvin 
paid  particular  attention  to  the  sexes  of  the  humming-birds  'n  Cen- 
tral America,  and  he  is  convinced  that  with  most  of  the  species  the 
males  are  in  excess;  thus  one  year  he  procured  204  specimens  belong- 
ing to  ten  species,  and  these  consisted  of  166  males  and  of  only  S^ 
females.  With  two  other  species  the  females  were  in  excess;  but 
the  proportions  apparently  vary  either  during  different  seasons  or  in 
different  localities;  for  on  one  occasion  the  males  of  Campglopterus 
hemileucurus  were  to  the  females  as  5  to  2.  and  on  another  occasion* 
in  exactly  the  reversed  ratio.  As  bearing  on  this  latter  point,  I  may 
add  that  Mr.  Powys  found  in  Corfu  and  Epirus  the  sexes  of  the 
chaffinch  keeping  apart,  and  "the  females  by  far  the  most  numer- 
ous;" while  in  Palestine,  Mr.  Tristram  found  "the  male  flocks 
appearing  greatly  to  exceed  "the  female  in  number. "f  So  again 
with  the  Quiscalus  major,  Mr,  G.  Taylor:}:  says,  that  in  Florida  there 
were  "  very  few  females  in  proportion  to  the  males,"  while  in  Hon- 
duras the  proportion  was  the  other  way,  the  species  there  having  the 
character  of  a  polygamist. 

Fish. — With  fish  the  proportional  numbers  of  the  sexes  can  be 
ascertained  only  by  catching  them  in  the  adult  or  nearly  adult  state; 
and  there  are  many  difficulties  in  arriving  at  any  just  conclusion. § 
Infertile  females  might  readily  be  mistaken  for  males,  as  Dr.  Giin- 
ther  has  remarked  to  me  in  regard  to  trout.  With  some  species  the 
males  are  believed  to  die  soon  after  fertilizing  the  ova.  With  many 
species  the  males  are  of  much  smaller  size  than  the  females,  so  that 
a  large  number  of  males  would  escape  from  the  same  net  by  which 
the  females  were  caught.  M.  Carbonnier,|  who  has  especially 
attended  to  the  natural  history  of  the  pike  {Esox  lucius),  states  that 
many  males,  owing  to  their  small  size,  are  devoured  by  the  larger 
females;  and  he  believes  that  the  males  of  almost  all  fish  are  exposed 
from  this  same  cause  to  greater  danger  than  the  females.  Neverthe- 
less, in  the  few  cases  in  which  the  proportional  numbers  have  been 
actually  observed,  the  males  appear  to  be  largely  in  excess.  Thus 
Mr.  R.  Buist,  the  superintendent  of  the  Stormontfield  exi^eriments, 

*" Ibis,"  vol.  ii,  p.  260,  as  quoted  in  "Gould's  Trochilidae,"  1861,  p.  52. 
For  the  foregoing  proportions,  I  am  indebted  to  Mr.  Salvin  for  a  table  of  his 
results. 

t  "  Ibis,"  1860,  p,  137;  and  1867,  p.  369. 

%  "  Ibis,"  1862.  p,  187. 

ILeuckart  quotes  Bloch  (Wagner,  "  Handworterbucb  der  Phys.,"  B.  iv, 
1853,  8.  77.1),  that  with  fish  there  are  twice  as  many  males  as  females. 

1  Quoted  in  the  "  Farmer,"  March  18, 1869,  p.  369. 


282  THE  bESGENT  OF  MAN. 

says  tliat  in  1865,  out  of  70  salmon  first  landed  for  tlie  purpose  of 
obtaining  the  ova,  upward  of  60  were  males.  In  1867  lie  again 
"  calls  attention  to  the  vast  disproportion  of  the  males  to  the  females. 
We  had  at  the  outset  at  least  ten  males  to  one  female."  Afterward 
females  sufficient  for  obtaining  ova  were  })rocured.  lie  adds,  "  from 
the  great  proportion  of  the  males,  Hiey  are  constantly  fightiug  and 
tearing  e£tch  other  on  the  spawning-beds."*  This  disproportion,  no 
doubt,  can  be  Jlccourited  for  in  part,  but  whether  wholly  is  doubtful, 
by  the  ma,les  ascending  the  rivers  before  the  females.  Mr.  F.  Buck- 
land  remarks  in  regard  to  trout,  that  "it  is  a  curious  fact  that  the 
males  preponderate  very  largely  in  number  over  the  females.  It 
invariably  happens  that  when  the  first  rush  of  fish  is  made  to  the 
net  there  will  be  at  least  seven  or  eight  males  to  one  female  found 
captive.  I  cannot  quite  account  for  this;  either  the  males  are  more 
numerous  than  the  females,  or  the  latter  seek  safety  by  concealment 
rather  than  flight,"  He  then  adds,  that  by  carefully  searching  the 
banks  sufficient  females  for  obtaining  ova  can  be  found,  f  Mr.  H. 
Lee  informs  me  that  out  of  212  trout  taken  for  this  purpose  in  Lord 
Portsmouth's  park,  150  were  males  and  62  females. 

The  males  of  the  Cyprinidae  likewise  seem  to  be  in  excess;  but  sev- 
eral members  of  this  family,  viz.,  the  carp,  tench,  bream  and  min- 
now, appear  regularly  to  follow  the  practice,  rare  in  the  animal  king- 
dom, of  polyandry;  tor  the  female  while  spawning  is  always  attended 
by  two  males,  one  on  each  side,  and  in  the  case  of  the  bream  by  three 
or  four  males.  This  fact  is  so  weh  known  that  it  is  always  recom- 
mended to  stock  a  pond  with  two  male  tenches  to  one  female,  or  at 
least  with  three  males  to  two  females.  With  the  minnow,  an  excel- 
lent observer  states,  that  on  the  spawning-beds  the  males  are  ten 
times  as  numerous  as  the  females;  when  a  female  comes  among  the 
males,  "  she  is  immediateh  pressed  closely  by  a  male  on  each  side; 
and  when  they  have  been  in  that  situation  for  a  time  are  superseded 
by  two  other  males."  % 

Insects. — In  this  great  class  the  Lepidoptera  almost  alone  afford 
means  for  judging  of  the  proportional  numbers  of  the  sexes;  for  they 
have  been  collected  with  special  care  by  many  good  observers,  and 
have  been  largely  bred  from  the  egg  or  caterpillar  state.  I  had  hoped 
that  some  breeders  of  silk-moths  might  have  kept  an  exact  record, 
but  after  writing  to  France  and  Italy,  and  consulting  various  treatises, 
I  cannot  find  that  this  has  ever  been  done.  The  general  opinion  ap- 
pears to  be  that  the  sexes  are  nearly  equal,  but  in  Italy,  as  I  hear 
from  Prof.  Canestrini,  many  breeders  are  convinced  that  the  females 
are  produced  in  excess.  This  same  naturalist,  however,  informs  me 
that  in  the  two  yearly  broods  of  the  Ailanthus  silk-moth  {Bombyx 
cynthia),  the  males  greatly  preponderate  in  the  first,  while  in  the 
second  the  two  sexes  are  nearly  equal,  or  the  females  rather  in 
excess. 

* "  The  Storm  on  tfield  Pisciciiltural  Experiments,"  1866,  p.  23.  The 
*'  Field  "  newspaper,  June  29,  1867. 

t  "  Land  and  Water,"  1868,  ;\  41. 

X  Yan-ell,  "  Hist.  British  Fishes,"  vol.  i,  1826,  p.  307;  on  the  Cyprimis  cai^iio, 
p.  asi;  on  the  Tinea  vulgaris,  p.  331;  on  the  Abramis  bmma,  p.  336.  See,  for  the 
minnow  {I^vcisms  phoxinm),  "  Loudon's  Mag.  of  Nat.  Hist.,"  vol.  v,  1832,  p.  682. 


pROPORTtON  OP  THE  sMM  ^83 

In  regard  to  butterflies  in  a  state  of  nature,  several  observers  have 
been  much  struck  by  the  apparently  fehormous  preponderance  of  the 
males.*  Thus  Mr.  Bates,  f  in  speaking  of  several  species,  about  a 
hundred  in  number,  which  inhabit  the  Upper  Amazons,  says  that 
the  males  are  much  more  numerous  than  the  females,  even  in  the 
proportion  of  100  to  1.  In  North  America,  Edwards,  who 
had  great  experience,  estimates  in  the  genus  Papilio  the  males  to  the 
females  as  4  to  1;  and  Mr.  Walsh,  who  informed  me  of  this 
statement,  says  that  with  P.  turnus  this  is  certainly  the  case.  In 
S.  Africa,  Mr.  R.  Trimen  found  the  males  in  excess  in  nineteen  spe- 
cies; X  aiid  in  one  of  these,  which  swarms  in  open  places,  he  estimated 
the  number  of  males  as  50  to  1  female.  With  another  species, 
in  which  the  males  are  numerous  in  certain  localities,  he  collected 
only  five  females  during  seven  years.  In  the  Island  of  Bourbon,  M. 
Maillard  states  that  the  males  of  one  species  of  Papilio  are  twenty 
times  as  numerous  as  the  females.  §  Mr.  Trimen  informs  me  that  as 
far  as  he  has  himself  seen,  or  heard  from  others,  it  is  rare  for  the 
females  of  any  butterfly  to  exceed  the  males  in  number;  but  three 
South  African  species  perhaps  offer  an  exception.  Mr.  Wallace|| 
states  that  the  females  of  Orrdthoptera;  crcesus,  in  the  Malay  Archi 
pelago,  are  more  common  and  more  easily  caught  than  the  males; 
but  this  is  a  rare  butterfly.  I  may  here  add  that  in  Hyperythra,  a 
genus  of  moths,  Guenee  says,  that  from  four  to  five  females  are  sent 
in  collections  from  India  for  one  male. 

When  this  subject  of  the  proportional  numbers  of  the  sexes  of 
insects  was  brought  before  the  Entomological  Society,^[  it  was 
generally  admitted  that  the  males  of  most  Lepidoptera,  in  the 
adult  or  imago  state,  are  caught  in  greater  numbers  than  the  females: 
but  this  fact  was  attributed  by  various  observers  to  the  more 
retiring  habits  of  the  females,  and  to  the  males  emerging  earlier 
from  the  cocoon.  This  latter  circumstance  is  well  known  to  occur 
with  most  Lepidoptera,  as  well  as  with  other  insects.  So  that,  as  M. 
Personnat  remarks,  the  males  of  the  domesticated  Bombyx  Tamamai 
are  useless  at  the  beginning  of  the  season,  and  the  females  at  the 
end,  from  the  want  of  mates.**  I  cannot,  however,  persuade  myself 
that  these  causes  suffice  to  explain  the  great  excess  of  males  in  the 
above  cases  of  certain  butterflies  which  are  extremely  common  in 
their  native  countries.  Mr.  Stainton,  who  has  paid  very  close  atten- 
tion during  many  years  to  the  smaller  moths,  infonns  me  that  when 
he  collected  them  in  the  imago  state,  he  thought  that  the  males  were 
ten  times  as  numerous  as  the  females,  but  that  since  he  has  reared 
them  on  a  large  scale  from  the  caterpillar  state  he  is  convinced  that 
the  females  are  the  more  numerous.     Several  entomologists  concur 

*Leuckart  quotes  Meinecke  (Wagner,  "  Handworterbuch  der  Phys.,"  B. 
Iv,  1853,  s.  775),  tnat  the  males  of  butterflies  are  three  or  four  times  as  numer- 
ous as  the  females. 

t  "  The  Naturalist  on  the  Amazons,"  vol.  ii,  1863,  pp,  2«,  347. 

X  "  Four  of  these  cases  are  given  by  Mr.  Trimen  in  his  "  Rhopalocera  AfricaB 
Australis." 

§  Quoted  by  Trimen,  "  Transact.  Ent.  Soc.,"  vol.  v,  part  iv,  1866,  p.  330. 

1 "  Transact.  Linn.  Soc.,"  vol.  xxv,  p.  37. 

1  •'  Proc.  Entomoloff.  Soc.,"  Feb.  17, 1868. 

**Quoted  by  Dr.  Wallace  in  "  Proc.  Ent.  Soc,"  3d  series,  vol.  v,  1867,  p.  487. 


284  I'H^  DESCENT  OF  MAN. 

in  this  view.  Mr.  Doubleday,  however,  and  some  others,  take  an 
opposite  view,  and  are  convinced  that  they  have  reared  from  the 
eggs  and  caterpillars  a  larger  proportion  of  males  than  of  females. 

Besides  the  more  active  habits  of  the  males,  their  earlier  emergence 
from  the  cocoon,  and  in  some  cases  their  frequenting  more  open 
stations,  other  causes  may  be  assigned  for  an  ajiparent  or  real  differ- 
ence in  the  proportional  numbers  of  the  sexes  of  Lepidoptera,  when 
captured  in  the  imago  state,  and  when  reared  from  the  egg  or  cater- 
pillar state.  I  hear  from  Prof.  Canestrini  that  it  is  believed  by  many 
breeders  in  Italy  that  the  female  caterpillar  of  the  silk-moth  suffers 
more  from  the  recent  disease  than  the  male;  and  Dr.  Staudinger 
informs  me  that  in  rearing  Lepidoptera  more  females  die  in  the 
cocoon  than  males.  With  many  species  the  female  caterpillar  is 
larger  than  the  male,  and  a  collector  would  naturally  choose  the 
finest  specimens,  and  thus  unintentionally  collect  a  larger  number  of 
females.  Three  collectors  have  told  me  that  this  was  their  practice; 
but  Dr.  Wallace  is  sure  that  most  collectors  take  all  the  speci- 
mens which  they  can  find  of  the  rarer  kinds,  which  alone  are  worth 
the  trouble  of  rearing.  Birds  when  surrounded  by  caterpillars 
would  probably  devour  the  largest;  and  Prof,  Canestrini  informs  me 
that  in  Italy  some  breeders  believe,  though  on  insufficient  evidence, 
that  in  the  first  broods  of  the  Ailanthus  silk-moth  the  wasps  destroy 
a  larger  number  of  the  female  than  of  the  male  caterpillars.  Dr. 
Wallace  further  remarks  that  female  caterpillars,  from  being  larger 
than  the  males,  require  more  time  for  their  development  and  con- 
sume more  food  and  moisture;  and  thus  they  would  be  exposed 
during  a  longer  time  to  danger  from  ichneumons,  birds,  etc.,  and  in 
times  of  scarcity  would  perish  in  greater  numbers.  Hence  it  appears 
quite  possible  that  in  a  state  of  nature,  fewer  female  Lepidoptera 
may  reach  maturity  than  males;  and  for  our  special  object  we  are 
concerned  with  their  relative  numbers  at  maturity,  when  the  sexes 
are  ready  to  propagate  their  kind. 

The  manner  in  which  the  males  of  certain  moths  congregate  in 
extraordinary  numbers  round  a  single  female,  apparently  indicates  a 
great  excess  of  males,  though  this  fact  may  perhaps  be  accounted 
for  by  the  earlier  emergence  of  the  males  from  their  cocoons.  Mr. 
Stainton  informs  me  that  from  twelve  to  twenty  males  may  often  be 
seen  congregated  round  a  female  Elachista  rufocinerea.  It  is  well 
known  that  if  a  virgin  Ladocampa  quereus  or  Saturnia  carpini  be 
exposed  in  a  cage,  vast  numbers  of  males  collect  round  her,  and  if 
confined  in  a  room  will  even  come  down  the  chimney  to  her.  Mr. 
Doubleday  believes  that  he  has  seen  from  fifty  to  a  hundred  males  of 
both  these  species  attracted  in  the  course  of  a  single  day  by  a  female 
in  confinement.  In  the  Isle  of  Wight,  Mr.  Trimen  exposed  a  box  in 
which  a  female  of  the  Lasiocampa  liad  been  confined  on  the  previous 
day,  and  five  males  soon  endeavored  to  gain  admittance.  In  Aus- 
tralia, M.  Verreaux,  having  placed  the  female  of  a  small  Bombyx  in 
a  box  in  his  pocket,  was  followed  by  a  crowd  of  males,  so  that  about 
200  entered  the  house  with  him.  * 

Mr.   Doubleday  has  called  my  attention  to  M.   Staudinger'sf  list 

*  Blanchard,  "  Metamorphoses,  Moeurs  des  Insectes,"  1868,  pp;  225-226. 
t  "  Lepidopteren-Doubletten  Liste,"  Berlin,  No.  x,  1866. 


PROPORTION  OF  THE  SEXES. 


286 


of  Lepidoptera,  which  ^ives  the  prices  of  the  males  and  females  of 
800  species  or  well-marked  varieties  of  butterflies  (Rhopalocera). 
The  prices  for  both  sexes  of  the  very  common  species  are  of  course 
the  same;  but  in  114  of  the  rarer  species  they  differ;  the  males 
being  in  all  cases,  excepting  one,  the  cheaper.  On  an  average  of  the 
prices  of  the  113  species,  the  price  of  the  male  to  that  of  the 
female  is  as  100  to  149;  and  this  apparently  indicates  that  inversely 
the  males  exceed  the  females  in  the  same  proportion.  About 
2,000  species  or  varieties  of  moths  (Heterocera)  are  catalogued, 
those  with  wingless  females  being  here  excluded  on  account 
of  the  difference  in  habits  between  the  two  sexes:  of  these 
2,000  species,  141  differ  in  price  according  to  sex,  the  males  of  130 
being  cheaper,  and  those  of  only  11  being  dearer  than  the  females. 
The  average  price  of  the  males  of  the  130  species,  to  that  of  the 
females,  is  as  100  to  143.  With  respect  to  the  butterflies  in  this 
price-list,  Mr.  Doubleday  thinks  (and  no  man  in  England  has  had 
more  experience),  that  there  is  nothing  in  the  habits  of  the  species 
which  can  account  for  the  difference  in  the  prices  of  the  two  sexes, 
and  that  it  can  be  accounted  for  only  by  an  excess  in  the  number 
of  the  males.  But  I  am  bound  to  add  that  Dr.  Staudinger  informs 
me  that  he  is  himself  of  a  different  opinion.  He  thinks  that  the 
less  active  habits  of  the  females  and  the  earlier  emergence  of  the 
males  will  account  for  his  collectors  securing  a  larger  number  of 
males  than  of  females,  and  consequently  for  the  lower  prices  of  the 
former.  With  respect  to  specimens  reared  from  the  caterpillar 
state.  Dr.  Staudinger  believes,  as  previously  stated,  that  a  greater 
number  of  females  than  of  males  die  while  confined  in  the  cocoons. 
He  adds  that  with  certain  species  one  sex  seems  to  preponderate  over 
the  other  during  certain  years. 

Of  direct  observations  on  the  sexes  of  Lepidoptera,  reared  either 
from   eggs  or  caterpillars,  I  have  received  only  the  few  following 


Males. 

Females . 

The  Rev.  J.  Hellins  *  of  Exeter  reared,  during  1868,  images 
of  73  species,  which  consisted  of 

Mr.  Albert  Jones  of  Eltham  reared,  during  1868,  imagos  of 
9  species,  which  consisted  of  

During  1869  he  reared  imagos  from  4  species,  consisting 

153 
159 
114 
180 

52 
224 

52 

137 
126 
112 

Mr.   Buckler  of    Emsworth,    Hants,  during  1869,  reared 
imagos  from  74  species,  consisting  of 

Dr.  Wallace  of  Colchester  reared  from  one  brood  of  Bom- 
l)vx  cvnthia                                            ... 

169 
48 

Dr.  Wallace  raised,  from  cocoons  of  Bombyx  Pernyi  sent 
from  China,  during  1869  

Dr.  Wallace  raised,  during  1868  and  1869,  from  two  lots  of 
cocoons  of  Bombj'x  yama-mai  

123 
46 

Total 

934 

761 

*This  naturalist  has  been  so  kind  as  to  send  me  some  results  from  former 
years,  in  which  the  females  seemed  to  preponderate ;  but  so  many  of  the 
figures  were  estimates  that  I  found  it  impossible  to  tabulate  them. 


286  THE  DESGKNT  OF  MAN, 

So  that  in  these  eight  lots  of  cocoons  and  eggs  males  were  pro- 
duced in  excess.  Taken  together  the  proj)ortion  of  males  is  as  122.7 
to  100  feradles.  But  the  numbers  are  hardly  large  enough  to  be 
trustworthy. 

On  the  whole,  from  these  various  sources  of  evidence,  all  pointing 
in  the  same  direction,  I  infer  that  with  most  species  of  Lepidopteru 
the  mature  males  generally  exceed  the  females  in  number,  whatever 
the  proportions  may  be  at  their  first  emergence  from  the  egg. 

With  reference  to  the  other  orders  of  insects,  I  have  been  able  to 
collect  very  little  reliable  information.  With  the  stag-beetle  {La- 
canus  cei'viis)  "  the  males  appear  to  be  much  more  numerous  than 
the  females:"  but  when,  as  Cornelius  remarked  during  1867,  an 
unusual  number  of  these  beetles  appeared  in  one  part  of  Germany, 
the  females  appeared  to  exceed  the  males  as  6  to  1.  With  one 
of  the  Elateridae,  the  males  are  said  to  be  much  more  numerous  than 
the  females,  and  "two  or  three  are  often  found  united  with  one 
female;*  so  that  here  polyandry  seems  to  prevail."  With  Siagonium 
(Staphylinidae),  in  which  the  males  are  furnished  with  horns,  ' '  the 
females  are  far  more  numerous  than  the  opposite  sex."  Mr.  Janson 
stated  at  the  Entomological  Society  that  the  females  of  the  bark- 
feeding  Tomicus  villosus^SLTe  so  common  as  to  be  a  plague,  while  the 
males  are  so  rare  as  to  be  hardly  known. 

It  is  hardly  worth  while  saying  anything  about  the  proportion  of 
the  sexes  in  certain  species  and  even  groups  of  insects,  for  the  males 
are  unknown  or  very  rare,  and  the  females  are  parthenogenetic, 
that  is,  fertile  without  sexual  union  ;  examples  of  this  are 
afforded  by  several  of  the  Cynipidse.f  In  all  the  gall-making 
CynipidsB  known  to  Mr.  Walsh,  the  females  are  four  or  five  times 
as  numerous  as  the  males;  and  so  it  is,  as  he  informs  me,  with  the 
gall-making  Cecidomyiidse  (Diptera).  With  some  common  species 
of  Saw-flies  (Tenthredinse)  Mr,  F.  Smith  has  reared  hundreds  of 
specimens  from  larvae  of  all  sizes,  but  .has  never  reared  a  single 
male;  on  the  other  hand,  Curtis  says,:|:  that  with  certain  species 
(Athalia)  bred  by  him,  the  males  were  to  the  females  as  6  to  1  ; 
while  exactly  the  reverse  occurred  with  the  mature  insects  of  the 
same  species  caught  in  the  fields.  In  the  family  of  bees,  Hermann 
Miiller^  collected  a  large  number  of  specimens  of  many  species,  and 
reared  others  from  the  cocoons,  and  counted  the  sexes.  He  found 
that  the  males  of  some  species  greatly  exceeded  the  females  in  num- 
ber; in  others  the  reverse  occurred;  and  in  others  the  two  sexes  were 
nearly  equal.  But  as  in  most  cases  the  males  emerge  from  the  co- 
coons l)efore  the  females,  they  are  at  the  commencement  of  the  breed- 
ing season  practically  in  excess.  Miiller  also  observed  that  the  rela- 
tive number  of  the  two  sexes  in  some  species  differed  much  in  differ- 
ent localities.  But  as  H.  Miiller  has  himself  remarked  to  me,  these 
remarks  must  be  received  with  some  caution,  as  one  sex  might  more 

*  Gunther's  "  Record  of  Zoological  Literature,"  1867,  p.  260.  On  the  excess 
of  female  Lucanus,  ibid.  p.  250.  On  the  males  of  Lucanus  in  England,  West- 
wood,  "Modern  Class  of  Insects,'' vol  i.  p.  187.   On  the  Siagonium,  ibid.  p.  172. 

t  Walsh  in  "The  American  Entomologist,"  vol.  i,  1869,  p.  103.  F.Smith, 
"  Record  of  Zoological  Literature,"  1867,  p.  328. 

t  "  Farm  Insects,"  pp.  45-46. 

§  "  Anwendung  der  Darwinschen  Lehre  Verh.  d.  n.  V.  Jahrg.,"  xxiv. 


PROPORTION  OF  THE  SEXES.  287 

easily  escape  observation  tLan  the  other.  Thus  his  brother  Fritz 
Miiller  has  noticed  in  Brazil  that  the  two  sexes  of  the  same  species  of 
bee  sometimes  frequent  different  kinds  of  flowers.  With  respect  to 
the  Orthoptera,  1  know  hardly  anything  about  the  relative  number  of 
the  sexes;  Korte,*  however,  says  that  out  of  500  locusts  which  he 
examined,  the  males  were  to  the  females  as  5  to  6.  With  the 
Neuroptera,  Mr.  Walsh  states  that  in  many,  but  by  no  means  in  all 
the  species  of  the  Odonatous  group,  there  is  a  great  overplus  of  males; 
in  the  genus  Hetaerina,  also,  the  males  are  generally  at  least  four 
times  as  numerous  as  the  females.  In  certain  species  in  the  genus 
Gomphus  the  males  are  equally  in  excess,  while  in  two  other  species 
the  females  are  twice  or  thrice  as  numerous  as  the  males.  In  some 
European  species  of  Psocus  thousands  of  females  may  be  collected 
without  a  single  male,  while  with  other  species  of  the  same  genus 
both  sexes  are  common,  f  In  England,  Mr.  MacLachlan  has  captured 
hundreds  of  the  female  Apatania  muliebris,  but  has  never  seen  the 
male;  and  of  Boreus  hyemalis  only  four  or  five  males  have  been  seen 
here.  J  With  most  of  these  species  (excepting  the  Tenthredinse)  there 
is  at  present  no  evidence  that  the  females  are  subject  to  partheno- 
genesis; and  thus  we  see  how  ignorant  we  are  of  the  causes  of  the 
apparent  discrepancy  in  the  proportion  of  the  two  sexes. 

In  the  other  classes  of  the  Articulata  I  have  been  able  to  collect 
still  less  information.  With  spiders,  Mr.  Blackwall,  who  has  care- 
fully attended  to  this  class  during  many  years,  writes  to  me  that  the 
males  from  their  more  erratic  habits  are  more  commonly  seen,  and 
therefore  appear  more  numerous.  This  is  actually  the  case  with  a 
few  species;  but  he  mentions  several  species  in  six  genera,  in  which 
the  females  appear  to  be  much  more  numerous  than  the  males.g  The 
small  size  of  the  males  in  comparison  with  the  females  (a  peculiarity 
which  is  sometimes  carried  to  an  extreme  degree),  and  their  widely 
different  appearance,  may  account  in  some  instances  for  their  rarity 
in  collections,  f 

Some  of  the  lower  Crustaceans  are  able  to  propagate  their  kind 
sexually,  and  this  will  account  for  the  extreme  rarity  of  the  males; 
thus  Von  Siebold^  carefully  examined  no  less  than  13,000  specimens 
of  Apus  from  twenty-one  localities,  and  among  these  he  found  only 
319  males.  With  some  other  forms  (as  Tanais  and  Cypris),  as  Fritz 
Miiller  informs  me,  there  is  reason  to  believe  that  the  males  are  much 
shorter-lived  than  the  females;  and  this  would  explain  their  scarcity, 
supposing  the  two  sexes  to  be  at  first  equal  in  number.  On  the  other 
hand,  Miiller  has  invariably  taken  far  more  males  than  females  of 
the  DiastylidaB  and  of  Cypridina  on  the  shores  of  Brazil;  thus  with  a 

*  "  Die  Strich,  Zug  oder  Wanderheuschrecke."  1828,  p.  20. 

+  "  Observations  on  North  American  Neuroptera,"  by  II.  Ha^en  and  B.  D. 
Walsh,  "  Proc.  Ent.  Soc,  Philadelphia,"  Oct.,  IS&J,  pp.  168,  223,  239. 

X  "  Proc.  Ent.  Soc,  London,"  Feb.  17,  1868. 

§  Another  ^"eat  authority  with  respect  to  this  class.  Prof.  Thorell,  of  Upsala 
("  On  European  Spiders,"  186S-1870,  part  i,  p.  205),  speaks  as  if  female  spiders 
were  jcenerally  commoner  than  the  males. 

II  See,  on  this  subject,  :Mr.  O.  P.  Cambridge,  as  quoted  in  "  Quarterly  Jour- 
nal of  Science,"  1868.  p.  429. 

^"Beitrage  zur  Parthenogenesis,"  p.  174. 


288  THE  DESCENT  OF  MAN. 

s])ecies  in  the  latter  genus,  63  specimens  cauglittLe  same  day  included 
57  males;  but  he  suggests  that  this  preponderance  may  be  due  to 
some  unknown  difference  in  the  habits  of  the  two  sexes.  With  one 
of  the  higher  Brazilian  crabs,  namely,  a  Gelasimus,  Fritz  Mtiller 
found  the  males  to  be  more  numerous  than  the  females.  According 
to  the  large  experience  of  Mr.  C.  Spence  Bate,  the  reverse  seems  to 
be  the  case  with  six  common  British  crabs,  the  names  of  which  he 
has  given  me. 

The  Proportion  of  the  Sexes  in  Relation  to  Natural 
Selection. — There  is  reason  to  suspect  that  in  some  cases 
man  has  by  selection  indirectly  influenced  his  own  sex- 
producing  powers.  Certain  women  tend  to  produce  during 
their  whole  lives  more  children  of  one  sex  than  of  the 
other;  and  the  same  holds  good  of  many  animals^  for 
instance,  cows  and  horses;  thus  Mr.  Wright,  of  Yeldersley 
House,  informs  me  that  one  of  his  Arab  mares,  though  put 
seven  times  to  different  horses,  produced  seven  fillies. 
Though  I  have  very  little  evidence  on  this  head,  analogy 
would  lead  to  the  belief  that  the  tendency  to  produce 
either  sex  would  be  inherited  like  almost  every  other 
peculiarity,  for  instance,  that  of  producing  twins;  and  con- 
cerning the  above  tendency  a  good  authority,  Mr.  J. 
Downing,  has  communicated  to  me  facts  which  seem  to 
prove  that  this  does  occur  in  certain  families  of  short-horn 
cattle.  Col.  Marshall*  has  recently  found  on  careful 
examination  that  the  Todas,  a  hill  tribe  of  India,  consist 
of  112  males  and  84  females  of  all  ages — that  is  in  a  ratio 
of  133.3  males  to  100  females.  The  Todas,  who  are  poly- 
androus  in  their  marriages,  during  former  times  invariably 
practiced  female  infanticide;  but  this  practice  has  now 
been  discontinued  for  a  considerable  period.  Of  the  chil- 
dren born  within  late  years  the  males  are  more  numerous 
than  the  females  in  the  proportion  of  124  to  100.  Col. 
.  Marshall  accounts  for  this  fact  in  the  following  ingenious 
manner:  "  Let  us  for  the  purpose  of  illustration  take  three 
families  as  representing  an  average  of  the  entire  tribe;  say 
that  one  mother  gives  birth  to  six  daughters  and  no  sons; 
a  second  mother  has  six  sons  only,  while  the  third  mother 
has  three  sons  and  three  daughters.  The  first  mother,  fol- 
lowing the  tribal  custom,  destroys  four  daughters  and  pre- 
serves two.  The  second  retains  her  six  sons.  The  third 
kills  two  daughters  and  keeps  one,  as  also  her  three  sons. 

*  "  The  Todas,"  1873,  pp.  100,  111,  194,  196, 


PROPORTION  OF  THE  SEXES.  289 

We  have  then  from  the  three  families  nine  sons  and  three 
daughters  with  which^  to  continue  the  breed.  But  while 
the  males  belong  to  families  in  which  the  tendency  to  pro- 
duce sons  is  great  the  females  are  of  those  of  a  converse 
inclination.  Thus  the  bias  strengthens  with  each  genera- 
tion until,  as  we  find,  families  grow  to  have  habitually 
more  sons  than  daughters."' 

That  this  result  would  follow  from  the  above  form  of 
infanticide  seems  almost  certain;  that  is  if  w^e  assume  that 
a  sex-producing  tendency  is  inherited.  But  as  the  above 
numbers  are  so  extremely  scanty  I  have  searched  for  addi- 
tional evidence,  but  cannot  decide  whether  what  I  have 
found  is  trustworthy;  nevertheless  the  facts  are,  perhaps, 
w^orth  giving.  The  Maories  of  Xew  Zealand  have  long 
practiced  infanticide  ;  and  Mr.  Fenton*  states  that  he 
"  has  met  with  instances  of  women  who  have  destroyed 
four,  six  and  even  seven  children,  mostly  females.  How- 
ever, the  universal  testimony  of  those  best  qualified  to 
judge  is  conclusive  that  this  custom  has  for  many  years 
been  almost  extinct.  Probably  the  year  1835  may  be 
named  as  the  period  of  its  ceasing  to  exist.''  Now 
among  the  Xew  Zealanders,  as  with  the  Todas,  male  births 
are  considerably  in  excess.  Mr.  Fenton  remarks  (p.  30): 
^'  One  fact  is  certain,  although  the  exact  period  of  the 
commencement  of  this  singular  condition  of  the  dispropor- 
tion of  the  sexes  cannot  be  demonstratively  fixed,  it  is  quite 
clear  that  this  course  of  decrease  was  in  full  operation 
during  the  years  of  1830  to  18M,  when  the  non-adult  pop- 
ulation of  1844  was  being  produced,  and  has  continued 
with  great  energy  up  to  the  present  time."  The  following 
statements  are  taken  from  5lr.  Fenton  (p.  26),  but  as  the 
numbers  are  not  large,  and  as  the  census  was  not  accu- 
rate, uniform  results  cannot  be  expected.  It  should  be 
borne  in  mind  in  this  and  the  following  cases,  that  the 
normal  state  of  every  population  is  an  excess  of  women,  at 
least  in  all  civilized  countries,  chiefly  owing  to  the  greater 
mortality  of  the  male  sex  during  youth,  and  parti}'  to  acci- 
dents of  all  kinds  later  in  life.  In  1858,  the  native  popula- 
tion of  Xew  Zealand  was  estimated  as  consisting  of  31,667 
males  and  24,  303  females  of  all  ages,  that  is,  in  the  ratio 

*  "  Aboriginal  Inhabitants  of  New  Zealand:  Government  Report," 
lb59,  p.  36. 


290  THhJ  DhJSCKNT  OF  MAN, 

of  130.3  males  to  100  females.  But  during  this  same  year 
and  in  certain  limited  districts,  tl>e  numbers  were  ascer- 
tained with  much  care,  and  the  males  of  all  ages  were  here 
753  and  the  females  61G;  that  is  in  the  ratio  of  122.2  males 
to  100  females.  It  is  more  important  for  us  that  during 
this  same  year  of  1858,  the  non-adult  males  within  the 
same  district  were  found  to  be  178,  and  the  non-adult 
females  142,  that  is  in  the  ratio  of  125.3  to  100.  It  may 
be  added  that  in  1844,  at  which  period  female  infanticide 
had  only  lately  ceased,  the  non-adult  males  in  one  district 
were  281,  and  the  non-adult  females  only  194,  that  is  in  the 
ratio  of  144.8  males  to  100  females. 

In  the  Sandwich  Islands,  the  males  exceed  the  females 
in  number.  Infanticide  was  formerly  practiced  there  to  a 
frightful  extent,  but  was  by  no  means  confined  to  female 
infants,  as  is  shown  by  Mr.  Ellis,*  and  as  I  have  been  informed 
by  Bishop  Staley  and  the  Rev.  Mr.  Coan.  Nevertheless, 
another  apparently  trustworthy  writer,  Mr.  Jarves,f  whose 
observations  apply  to  the  whole  archipelago,  remarks: 
'^  Numbers  of  women  are  to  be  found  who  confess  to  the 
murder  of  from  three  to  six  or  eight  children,"  and  he  adds, 
"  females  from  being  considered  less  useful  than  males 
were  more  often  destroyed."  From  what  is  known  to 
occur  in  other  parts  of  the  world  this  statement  is 
probable;  but  must  be  received  with  much  caution.  The 
practice  of  infanticide  ceased  about  the  year  1819,  when 
idolatry  was  abolished  and  missionaries  settled  in  the 
islands.  A  careful  census  in  1839  of  the  adult  and  taxable 
men  and  women  in  the  island  of  Kauai  and  in  one  district 
of  Oahu  (Jarves,  p.  404),  gives  4,723  males  and  3,77G 
females;  that  is  in  the  ratio  of  125.08  to  100.  At  the  same 
time  the  number  of  males  under  fourteen  years  in  Kauai 
and  under  eightecTi  in  Oahu  was  1,797,  and  of  females  of 
the  same  ages  1,429;  and  here  we  have  the  ratio  of  125.75 
males  to  100  females. 

In  a  census  of  all  the  islands  in  1850,;];  the  males  of  all 
ages  amount  to  36,272,  and  the  females  to  33,128,  or  as 
109.49  to  100.     The  males  under  seventeen  years  amounted 

*  "  Narrative  of  a  Tour  through  Hawaii,"  1826.  p.  298. 
f  "  History  of  the  Sandwich  Islands/'  1843,  p.  93. 
X  This  is  given  in  the  Kev.  H.  T.  Cheever's  "  Life  in  the  SaodwicU 
Islands,"  1851   p.  277- 


PROPonrioN  OF  the  sexes.  291 

to  10,773,  and  the  females  under  the  same  age  to  9,593,  or 
as  112.3  to  100.  From  the  census  of  1872  the  proportioR 
of  males  of  all  ages  (including  half-castes)  to  females,  is  as 
125.36  to  100.  It  must  be  borne  in  mind  that  all  these 
returns  for  the  Sandwich  Islands  give  the  projx)rtion  of 
living  males  to  living  females,  and  not  of  the  births;  and 
judging  from  all  civilized  countries  the  proportion  of  males 
would  have  been  considerably  higher  if  the  numbers  had 
referred  to  births.* 

From  the  several  foregoing  cases  we  have  some  reason  to 
believe  that  infanticide  practiced  in  the  manner  above 
explained,  tends  to  make  a  male-producing  race;  but  I  am 
far  from  supposing  that  this  practice  in  the  case  of  man,  or 
some  analogous  process  with  other  species,  has  been  the  sole 
determining  cause  of  an  excess  of  males.  There  may  be 
some   unknown  law  leading  to  this  result  in  decreasing 

*Dr.  Coulter,  in  describing  ("  Journal  R.  Geograph.  Soc,"  vol.  v, 
1835,  p.  67)  the  state  of  California  about  the  year  1830,  says  that  the 
natives,  reclaimed  by  the  Spanish  missionaries,  have  nearly  all  per- 
ished, or  are  perishing,  although  well  treated,  not  driven  from  their 
native  land,  and  kept  from  the  use  of  spirits.  He  attributes  this,  in 
great  part,  to  the  undoubted  fact  that  the  men  greatly  exceed  the 
women  in  number;  but  he  does  not  know  whether  this  is  due  to  a 
failure  of  female  oflEspring,  or  to  more  females  dying  during  early 
youth.  The  latter  alternative,  according  to  all  analogy,  is  very 
improbable.  He  adds  that  "infanticide,  properly  so  called,  is  not 
common,  though  very  frequent  resource  is  had  to  abortion."  If  Dr. 
Coulter  is  correct  about  infanticide,  this  case  cannot  be  advanced  in 
support  of  Col,  Marshall's  view.  From  the  rapid  decrease  of  the 
reclaimed  natives,  we  may  suspect  that,  as  in  the  cases  lately  given, 
their  fertility  has  been  diminished  from  changed  habits  of  life.  I 
had  hoped  to  gain  some  light  on  this  subject  from  the  breeding  of 
dogs;  inasmuch  as  in  most  breeds,  with  the  exception,  perhaps,  of 
greyhounds,  many  more  female  puppies  are  destroyed  than  males, 
ju.st  as  with  the  Toda  infants.  Mr.  Cupples  assures  me  that  this  is 
usual  with  Scotch  deer-hounds.  Unfortunately  I  know  nothing  of 
the  proiKirtion  of  the  sexes  in  any  breed,  excepting  greyhounds,  and 
there  the  male  births  are  to  the  females  as  110.1  to  100.  Now  from 
inquiries  made  from  many  breeders,  it  seems  that  the  females  are  in 
some  respects  more  esteemed,  though  otherwise  troublesome;  and  it 
does  not  appear  that  the  female  puppies  of  the  best-bred  dogs  are 
systematically  destroyed  more  than  the  males,  though  this  does  some- 
times take  place  to  a  limited  extent.  Therefore  I  am  unable  to 
decide  whether  we  can,  on  the  above  principles,  account  for  the  pre- 
ponderance of  male  births  in  greyhounds.  On  the  other  hand,  we 
liave  seen  that  with  horses,  cattle  and  sheep,  which  are  too  valuable 
for  the  young  of  either  sex  to  be  destroyed,  if  there  is  any  difference, 
the  females  are  slightly  in  excess. 


292  THE  DESCENT  OF  MAN. 

races,  which  have  already  become  somewhat  infertile. 
Besides  the  several  causes  previously  alluded  to,  tlie  greater 
facility  of  parturition  among  savages,  and  the  less  conse- 
quent injury  to  their  male  infants,  would  tend  to  increase 
the  proportion  of  live-born  males  to  females.  There  does 
not,  however,  seem  to  be  any  necessary  connection  between 
savage  life  and  a  marked  excess  of  males;  that  is  if  we  may 
judge  by  the  character  of  the  scanty  offspring  of  the  lately 
existing  Tasmanians  and  of  the  crossed  offspring  of  the 
Tahitians  now  inhabiting  Norfolk  Island. 

As  the  males  and  females  of  many  animals  differ  some- 
what in  habits,  and  are  exposed  in  different  degrees  to 
danger,  it  is  probable  that  in  many  cases  more  of  one  sex 
than  of  the  other  are  habitually  destroyed.  But  as  far  as  I 
can  trace  out  the  complication  of  causes  an  indiscriminate 
though  large  destruction  of  either  sex  would  not  tend  to 
modify  the  sex-producing  power  of  the  species.  With 
strictly  social  animals,  such  as  bees  or  ants,  which  produce 
a  vast  number  of  sterile  and  fertile  females  in  comparison 
with  the  males,  and  to  whom  this  preponderance  is  of  para- 
mount importance,  we  can  see  that  those  communities 
would  flourish  best  which  contained  females  having  a 
strong  inherited  tendency  to  produce  more  and  more 
females;  and  in  such  cases  an  unequal  sex-producmg  ten- 
dency would  be  ultimately  gained  through  natural  selection. 
With  animals  living  in  herds  or  troops  in  which  the  males 
come  to  the  front  and  defend  the  herd,  as  with  the  bisons 
of  North  America  and  certain  baboons,  it  is  conceivable 
that  a  male-producing  tendency  might  be  gained  by  natural 
selection;  for  the  individuals  of  the  better  defended  herds 
would  leave  more  numerous  descendants.  In  the  case  of 
mankind  the  advantage  arising  from  having  a  jireponderance 
of  men  in  the  tribe  is  supposed  to  be  one  chief  cause  of 
the  practice  of  female  infanticide. 

In  no  case,  as  far  as  we  can  see,  would  an  inherited  ten- 
dency to  produce  both  sexes  in  equal  numbers  or  to  produce 
one  sex  in  excess,  be  a  direct  advantage  or  disadvantage  to 
certain  individuals  more  than  to  others;  for  instance,  an 
individual  with  a  tendency  to  produce  more  males  than 
females  would  not  succeed  better  in  the  battle  for  life  than 
an  individual  with  an  opposite  tendency;  and  therefore  a 
tendency  of  this  kind  could  not  be  gained  through  natural 
selection,      Nevertheless,    there  are   certain  animals   (for 


PROPORTION  OF  THE  SEXES.  293 

instance,  fishes  and  cirripedes)  in  which  two  or  more  males 
appear  to  be  necessary  for  the  fertilization  of  the  female; 
and  the  males  accordingly  largely  preponderate,  but  it  is 
by  no  means  obvious  how  this  male-producing  tendency 
could  have  been  acquired.  I  formerly  thought  that  when 
a  tendency  to  produce  the  two  sexes  in  equal  numbers  was 
advantageous  to  the  species  it  would  follow  from  natural 
selection,  but  I  now  see  that  the  whole  problem  is  so  intri- 
cate that  it  is  safer  to  leave  its  solution  for  the  future. 


294  i'ti^  i)E8VkNT  OP  MAi^. 


CHAPTER  IX. 

SECONDARY  SEXUAL   CHARACTERS  IN  THE   LOWER   CLASSES 
OF  THE   ANIMAL   KINGDOM. 

These  characters  absent  in  the  lowest  classes — Brilliant  colors — 
Mollusca  —  Annelids — Crustacea,  secondary  sexual  characters 
strongly  devoloped;  dimorphism;  color;  characters  not  acquired 
before  maturity — Spiders,  sexual  colors  of;  stridulation  by  the 
males — Myriapoda. 

With  animals  belonging  to  the  lower  classes,  the  two 
sexes  are  not  rarely  united  in  the  same  individual,  and  there- 
fore secondary  sexual  characters  cannot  be  developed.  In 
many  cases  where  the  sexes  are  separate  both  are  perma- 
nently attached  to  some  support,  and  the  one  cannot  search 
or  struggle  for  the  other.  Moreover  it  is  almost  certain 
that  these  animals  have  too  imperfect  senses  and  much  too 
low  mental  powers  to  appreciate  each  other's  beauty  or 
other  attractions,  or  to  feel  rivalry. 

Hence  in  these  classes  or  sub-kingdoms,  such  as  the  Pro- 
tozoa, Coelenterata,  Echinodermata,  Scolecida  secondary 
sexual  characters  of  the  kind  which  we  have  to  consider  do 
not  occur;  and  this  fact  agrees  with  the  belief  that  such 
characters  in  the  higher  classes  have  been  acquired  through 
sexual  selection,  which  depends  on  the  will,  desire  and 
choice  of  either  sex.  Nevertheless  some  few  apparent 
exceptions  occur;  thus,  as  I  hear  from  Dr.  Baird,  the  males 
of  certain  Entozoa  or  internal  parasitic  worms  differ  slightly 
in  color  from  the  females;  but  we  have  no  reason  to  sup- 
pose that  such  differences  have  been  augmented  through 
sexual  selection.  Contrivances  by  which  the  male  holds 
the  female,  and  which  are  indispensable  for  the  propaga- 
tion of  the  species,  are  independent  of  sexual  selection,  and 
have  been  acquired  through  ordinary  selection. 

Many  of  the  lower  animals,  whether  hermaphrodites  or 
with  separate  sexes,  are  ornamented  with  the  most  brilliant 
tints,  or  are  shaded  and  striped  in  an  elegant  manner;  for 
instance,  many  corals  and  sea-anemones   (Actiniae),  some 


SkWaL  SfSlEGTIOM.  296 

jeii^^-fish  (Medusae,  Porpita,  etc.),  some  Planariae,  many 
star-fishes,  Echini,  Ascidians,  etc.;  but  we  may  conchide 
from  the  reasons  already  indicated,  namely,  the  union  of 
the  two  sexes  in  some  of  these  animals,  the  permanently 
affixed  condition  of  others,  and  the  low  mental  powers  of 
all  that  such  colors  do  not  serve  as  a  sexual  attraction  and 
have  not  been  acquired  through  sexual  selection.  It 
should  be  borne  in  mind  that  in  no  case  have  we  sufficient 
evidence  that  colors  have  been  thus  acquired,  except  where 
one  sex  is  much  more  brilliantly  or  conspicuously  colored 
than  the  other,  and  where  there  is  no  difference  in  habits 
between  the  sexes  sufficient  to  account  for  their  different 
colors.  But  the  evidence  is  rendered  as  complete  as  it  can 
ever  be  only  when  the  more  ornamented  individuals,  almost 
always  the  males,  voluntarily  display  their  attractions 
before  the  other  sex;  for  we  cannot  believe  that  such  dis- 
play is  useless,  and  if  it  be  advantageous  sexual  selection 
will  almost  inevitably  follow.  We  may,  however,  extend 
this  conculsion  to  both  sexes  when  colored  alike  if  their 
colors  are  plainly  analogous  to  those,  of  one  sex  alone  in 
certain  other  species  of  the  same  group. 

How,  then,  are  we  to  account  for  the  beautiful  or  even 
gorgeous  colors  of  many  animals  in  the  lowest  classes?  It 
appeal's  doubtful  whether  such  colors  often  serve  as  a  pro- 
tection; but  that  we-  may  easily  err  on  this  head  will  be 
admitted  by  every  one  who  reads  Mr.  Wallace's  excellent 
essay  on  this  subject.  It  would  not,  for  instance,  at  first 
occur  to  any  one  that  the  transparency  of  the  Medusae,  or 
jelly-fish,  is  of  the  highest  service  to  them  as  a  protection; 
but  Avhen  we  are  reminded  by  Hackel  that  not  only  the 
Medusae  but  many  floating  mollusca,  crustaceans  and  even 
small  oceanic  fishes  partake  of  this  same  glass-like  appear- 
ance, often  accompanied  by  prismatic  colors,  we  can  hardly 
doubt  that  they  thus  escape  the  notice  of  pelagic  birds  and 
other  enemies.  M.  Giard  is  also  convinced*  that  the 
bright  tints  of  certain  sponges  and  ascidians  serve  as  a  pro- 
tection. Conspicuous  colors  are  likewise  beneficial  to  many 
animals  as  a  warning  to  their  would-be  devourers  that  they 
are  distasteful,  or  that  they  possess  some  special  means  of 
defense;  but  this  subject  will  be  discussed  more  conven- 
iently hereafter. 

We  can  in  our  ignorance  of  most  of  the  lowest  animals 

*  "  Archives  de  Zoolog.  Exper.,"  Oct.,  1872,  p.  563. 


206  TItE  Di^SCKN'r  OP  MAN. 

only  say  that  their  "bright  tints  result  either  from  the 
chemical  nature  or  the  minute  structure  of  their  tissues 
independently  of  any  benefit  thus  derived.  Hardly  any 
color  is  finer  than  that  of  arterial  blood;  but  there  is  no 
reason  to  suppose  that  the  color  of  the  blood  is  in  itself 
any  advantage;  and  though  it  adds  to  the  beauty  of  the 
maiden's  cheek,  no  one  will  pretend  that  it  has  been 
acquired  for  this  purpose.  So  again  with  many  animals, 
especially  the  lower  ones,  the  bile  is  richly  colored;  thus,  as 
I  am  informed  by  Mr.  Hancock,  the  extreme  beauty  of  the 
Eolidae  (naked  sea-slugs)  is  chiefly  due  to  the  biliary  glands 
being  seen  through  the  translucent  integuments  —  this 
beauty  being  probably  of  no  service  to  these  animals.  The 
tints  of  the  decaying  leaves  in  an  American  forest  are 
described  by  every  one  as  gorgeous;  yet  no  one  supposes 
that  these  tints  are  of  the  least  advantage  to  the  trees. 
Bearing  in  mind  how  many  substances  closely  analogous  to 
natural  organic  compounds  have  been  recently  formed  by 
chemists,  and  which  exhibit  the  most  splendid  colors,  it 
would  have  been  a  'strange  fact  if  substances  similarly 
colored  had  not  often  originated,  independently  of  any 
useful  end  thus  gained,  in  the  complex  laboratory  of  living 
organisms. 

The  Sub  Kingdom  of  the  Mollusha. — Throughout  this 
great  division  of  the  animal  kingdom,  as  far  as  I  can  dis- 
cover, secondary  sexual  characters,  such  as  we  are  here  con- 
sidering, never  occur.  ISTor  could  they  be  expected  in  the 
three  lowest  classes,  namely,  in  the  Ascidians,  Polyzoa  and 
Brachiopods  (constituting  the  Molluscoida  of  some  authors), 
for  most  of  these  animals  are  permanently  affixed  to  a  sup- 
port or  have  their  sexes  united  in  the  same  individual.  In 
the  Lamellibranchiata,  or  bivalve  shells,  hermaphroditism 
is  not  rare.  In  the  next  higher  class  of  the  Gasteropoda, 
or  univalve  shells,  the  sexes  are  either  united  or  separate. 
But  in  the  latter  case  the  males  never  possess  special  organs 
for  finding,  securing,  or  charming  the  females,  or  for  fight- 
ing with  other  males.  As  I  am  informed  by  Mr.  Gwyn 
Jeffreys,  the  sole  external  dilference  between  the  sexes  con- 
sists in  the  shell  sometimes  differing  a  little  in  form;  for 
instance,  the  shell  of  the  male  periwinkle  (Littorina 
lUtorea)  is  narrower  and  has  a  more  elongated  spire  than 
that  of  the  female.     But  differences  of  this  nature,  it  may 


M0LLUSK8.  297 

be  presumed,  are  directly  connected  with  the  act  of  repro- 
duction, or  with  the  development  of  the  ova. 

The  Gasteropoda,  though  capable  of  locomotion  and 
furnished  with  imperfect  eyes,  do  not  appear  to  be  endowed 
with  sufficient  mental  powers  for  the  members  of  the  same 
sex  to  struggle  together  in  rivalry,  and  thus  to  acquire 
secondary  sexual  characters.  Nevertheless  with  the  pul- 
moniferous  gasteropods,  or  land-snails,  the  pairing  is  pre- 
ceded by  courtship;  for  these  animals,  though  hermaphro- 
dites, are  compelled  by  their  structure  to  pair  together. 
Agassiz  remarks:*  ^*  Quiconque  a  eu  Toccasion  d'observer 
les  amours  des  lima9ons,  ne  saurait  mettre  en  doute  la 
seduction  deployee  dans  les  mouvements  et  les  allures  qui 
preparent  et  accomplissent  le  double  embrassement  de  ces 
hermaphrodites."  These  animals  appear  also  susceptible  of 
some  degree  of  permanent  attachment ;  an  accurate 
observer,  Mr.  Lonsdale,  informs  me  that  he  placed  a  pair 
of  land-snails  {Helix  pomatia),  one  of  which  was  weakly, 
into  a  small  and  ill-provided  garden.  After  a  short  time 
the  strong  and  healthy  individual  disappeared,  and  was 
traced  by  its  track  of  slime  over  a  wall  into  an  adjoining 
well-stocked  garden.  Mr.  Lonsdale  concluded  that  it  had 
deserted  its  sickly  mate;  but,  after  an  absence  of  twenty- 
four  hours,  it  returned,  and  apparently  communicated  the 
result  of  its  successful  exploration,  for  both  then  started 
along  the  same  track  and  disappeared  over  the  wall. 

Even  in  the  highest  class  of  the  Molluska,  the  Cephalo- 
podo  or  cuttle-fishes,  in  which  the  sexes  are  separate, 
secondary  sexual  characters  of  the  present  kind  do  not,  as 
far  as  I  can  discover,  occur.  This  is  a  surprising  circum- 
stance, as  these  animals  possess  highly-developed  sense- 
organs  and  have  considerable  mental  powers,  as  will  be 
admitted  by  every  one  who  has  watched  their  artful  endeav- 
ors to  escape  from  an  enemy.  \  Certain  Cephalopoda,  how- 
ever, are  characterized  by  one  extraordinary  sexual  charac- 
ter, namely  that  the  male  element  collects  within  one  of 
the  arms  or  tentacles,  which  is  then  cast  off,  and  clinging 
by  its  sucking-disks  to  the  female,  lives  for  a  time  an  inde- 
pendent life.  So  completely  does  the  cast-off  arm  resemble 
a  separate  animal,  that  it  was  described  by  Cuvier  as  a  para- 

*  "  De  I'Espece  et  de  la  Class,"  etc.,  1869,  p.  106. 
\  See,  for  instance,  the  account  wbicli  I  have  given  in  my  "  Jour- 
nal of  Researches,"  1845,  p.  7. 


298  THE  DESCENT  OF  MAN. 

sitic  worm  under  the  name  of  Hectocotyle.  But  this  mar- 
velous structure  may  be  classed  as  a  primary  rather  than  as 
a  secondary  sexual  character. 

Although  with  the  Molluska  sexual  selection  does  not 
seem  to  have  come  into  play ;  yet  many  univalve  and 
bivalve  shells,  such  as  volutes,  cones,  scallops,  etc.,  are 
beautifully  colored  and  shaped.  The  colors  do  not  appear 
in  most  cases  to  be  of  any  use  as  a  protection;  they  are 
probably  the  direct  result,  as  in  the  lowest  classes,  of  the 
nature  of  the  tissues;  the  patterns  and  the  sculpture  of  the 
shell  depending  on  its  maimer  of  growth.  The  amount  of 
light  seems  to  be  influential  to  a  certain  extent ;  for 
although,  as  repeatedly  stated  by  Mr.  Gwyn  Jeffreys,  the 
shells  of  some  species  living  at  a  profound  depth  are  brightly 
colored,  yet  we  generally  see  the  lower  surfaces,  as  well  as 
the  parts  covered  by  the  mantle,  less  highly  colored  than 
the  upper  and  exposed  surfaces.*  In  some  cases,  as  with 
shells  living  among  corals  or  brightly  tinted  sea-weeds,  the 
briglit  colors  may  serve  as  a  protection,  f  But  that  many 
of  the  nudi-branch  molluska,  or  sea-slugs,  are  as  beauti- 
fully colored  as  any  shells,  may  be  seen  in  Messrs.  Alder 
and  Hancock's  magnificent  work;  and  from  information 
kindly  given  me  by  Mr.  Hancock,  it  seems  extremely 
doubtful  whether  these  colors  usually  serve  as  a  protection. 
With  some  species  this  may  be  the  case,  as  with  one  kind 
which  lives  on  the  green  leaves  of  algae,  and  is  itself  bright- 
green.  But  many  brightly-colored,  white,  or  otherwise 
conspicuous  species,  do  not  seek  concealment;  while  again 
some  equally  conspicuous  species,  as  well  as  other  dull- 
colored  kinds,  live  under  stones  and  in  dark  recesses.  So 
that  with  these  nudibranch  mollusks,  color  apparently  does 
not  stand  in  any  close  relation  to  the  nature  of  the  places 
which  they  inhabit. 

These  naked  sea-slugs  are  hermaphrodites,  yet  they  pair 
together,  as  do  land-snails,  many  of  which  have  extremely 
pretty  shells.     It  is  conceivable  that  two  hermaphrodites, 

*I  have  given  ("Geolog.  Observations  on  Volcanic  Islands,"  1844, 
p.  53)  a  curious  instance  of  the  influence  of  light  on  the  colors  of  a 
frondescent  incrustation,  deposited  by  the  surf  on  the  coast-rocks  of 
Ascension,  and  formed  by  the  solution  of  triturated  sea-shells. 

f  Dr.  Morse  has  lately  discussed  this  subject  in  his  paper  on  the 
A<laptive  Coloration  of  Molluska,  "  Proc.  Boston  Soc.  of  Nat.  Hist.," 
vol.  xiv,  April,  1871. 


CRUSTACEANS.  ^09 

attracted  by  each  other's  greater  beauty,  might  unite 
and  leave  offspring  which  would  inherit  their  parents' 
greater  beauty.  But  with  such  lowly-organized  creatures 
this  is  extremely  improbable.  Nor  is  it  at  all  obvious  how 
the  offspring  from  the  more  beautiful  pairs  of  hermaphro- 
dites would  have  any  advantage  over  the  offspring  of  the 
less  beautiful,  so  as  to  increase  in  number,  unless  indeed 
vigor  and  beauty  generally  coincided.  We  have  not  here 
the  case  of  a  number  of  males  becoming  mature  before 
the  females,  with  the  more  beautiful  males  selected  by  the 
more  vigorous  females.  If,  indeed,  brilliant  colors  were 
beneficial  to  a  hermaphrodite  animal  in  relation  to  its  gen- 
eral habits  of  life,  the  more  brightly-tinted  individuals  would 
succeed  best  and  would  increase  in  number;  but  this  would 
be  a  case  of  natural  and  not  of  sexual  selection. 

Sub-lcingdom  of  the  Vermes  —  Annelida  {or  Sea- 
worms). — In  this  class,  although  the  sexes,  when  separate, 
sometimes  differ  from  each  other  in  characters  of  such  im- 
portance that  they  have  been  placed  under  distinct  genera 
or  even  families,  yet  the  differences  do  not  seem  of  the  kind 
which  can  be  safely  attributed  to  sexual  selection.  These 
animals  are  often  beautifully  colored,  but  as  the  sexes  do 
not  differ  in  this  respect  we  are  but  little  concerned  with 
them.  Even  the  Nemertians,  though  so  lowly  organized, 
*'  vie  in  beauty  and  variety  of  coloring  with  any  other 
group  in  the  vertebrate  series;"  yet  Dr.  Mcintosh  *  cannot 
discover  that  these  colors  are  of  any  service.  The  sedentary 
annelids  become  duller-colored,  according  to  M.  Quatre- 
fages,t  after  the  period  of  reproduction;  and  this  I  pre- 
sume may  be  attributed  to  their  less  vigorous  condition  at 
that  time.  All  these  worm-like  animals  apparently  stand 
too  low  in  the  scale  for  the  individuals  of  either  sex  to  exert 
any  choice  in  selecting  a  partner,  or  for  the  individuals  of 
the  same  sex  to  struggle  together  in  rivalry. 

Sub -kingdom  of  the  Arthropoda — Crustacea.  —  In 
this  great  class  we  first  meet  with  undoubted  secondary 
sexual  characters,  often  developed  in  a  remarkable  manner. 

*See  his  beautiful  monograph  on  "  British  Annelids,"  part  i.  1873, 
p.  8. 

f  See  M.  Perrier,  "  TOrigine  de  THomme  d'apres  Darwin,"  "  Revue 
Scientifique,"  Feb.,  1873,  p.  866. 


300  THE  DESCENT  OF  MAN. 

Unfortunately  the  habits  of  crustaceans  are  very  imper- 
fectly known,  and  we  cannot  explain  the  uses  of  many 
structures  peculiar  to  one  sex.  With  the  lower  parasitic 
species  the  males  are  of  small  size,  and  tliey  alone  are  fur- 
nished with  perfect  swimming  legs,  atennae  and  sense- 
organs;  the  females  being  destitute  of  these  organs,  with 
their  bodies  often  consisting  of  a  mere  distorted  mass.  But 
these  extraordinary  differences  between  the  two  sexes  are  no 
doubt  related  to  their  widely  different  habits  of  life,  and 
consequently  do  not  concern  us.  In  various  crustaceans, 
belonging  to  distinct  families,  the  anterior  attennse  are  fur- 
nished with  peculiar  thread-like  bodies,  which  are  believed 
to  act  as  smelling-organs,  and  these  are  much  more  numerous 
in  the  males  than  in  the  females.  As  the  males,  without  any 
unusual  development  of  their  olfactory  organs,  would  almost 
certainly  be  able  sooner  or  later  to  find  the  females,  the 
increased  number  of  the  smelling-threads  has  probably  been 
acquired  through  sexual  seclection,  by  the  better  provided 
males  having  been  the  more  successful  in  finding  partners 
and  in  producing  offspring.  Fritz  Miiller  has  described  a 
remarkable  dimorphic  species  of  Tanais  in  which  the  male 
is  represented  by  two  distinct  forms  which  never  graduate 
into  each  other.  In  the  one  form  the  male  is  furnished 
with  more  numerous  smelling-threads,  and  in  the  other 
form  with  more  powerful  and  more  elongated  chelae  or 
pincers  which  serve  to  hold  the  female.  Fritz  Miiller  sug- 
gests that  these  differences  between  the  two  male  forms  of 
the  same  species  may  have  originated  in  certain  individuals 
having  varied  in  the  number  of  the  smelling-threads,  while 
other  individuals  varied  in  the  shape  and  size  of  their 
chelae;  so  that  of  the  former  those  which  were  best  able  to 
find  the  female,  and  of  the  latter  those  which  were  best 
able  to  hold  her,  have  left  the  greatest  number  of  progeny 
to  inherit  their  respective  advantages.* 

In  some  of  the  lower  crustaceans  the  right  anterior 
antenna  of  the  male  differs  greatly  in  structure  from  the 
left,  the  latter  resembling  in  its  simple  tapering  joints  the 
antennae  of  the  female.  In  the  male  the  modified  antenna 
is  either  swollen  in  the  middle  or  angularly  bent  or  con- 

***  Facts  and  Arguments  for  Darwin,"  English  translat.,  1869,  p. 
20.  See  the  previous  discussion  on  the  olfactory  threads.  Sars  has 
described  a  somewhat  analogous  case  (as  quoted  in  "  Nature,"  1870, 
p.  455)  in  a  Norwegian  crustacean,  the  Potitoporcia  affinis. 


CRUSTACEANS. 


301 


verted  (fig.  4)  into  an  elegant  and  sometimes  wonderfully 
complex  prehensile  organ.*  It  serves,  as  I  hear  from  Sir 
J.  Lubbock,  to  hold  the  female,  for  this  same  purpose-one 
of  the  two  posterior  legs  {b)  on  the  same  side  of  the  body 
is  converted  into  a  forceps.  In  another  family  the  inferior 
or  posterior  antennae  are  '^curiously  zigzagged^'  in  the 
males  alone. 

In    the    higher    crustaceans    the  a 

anterior  legs  are  developed  into 
chelae  or  pincers;  and  these  are  gen- 
erally larger  in  the  male  than  in  the 
female — so  much  so  that  the  market 
value  of  the  male  edible  crab  ( Cancer 
paguriis),  according  to  Mr.  C.  Spence 
Bate,  is  five  times  as  great  as  that  of 
the  female.  In  many  species  the 
chelae  are  of  unequal  size  on  the 
opposite  side  of  the  body,  the  right- 
hand  one  being,  as  I  am  informed  by 
Mr.  Bate,  generally  though  not 
invariably  the  largest.  This  ine- 
quality is  also  often  much  greater  in 
the  male  than  in  the  female.  The 
two  chelae  of  the  male  often  differ 
in  structure  (figs.  5,  6  and  7),  the 
smaller  one  resembling  that  of  the 
female.  What  advantage  is  gained 
by  their  inequality  in  size  on  the 
opposite  sides  of  the  body  and  by  the 
inequality  being  much  greater  in  the 
the  male  than  in  the  female;  and 
why  when  they  are  of  equal  size  both 
are  often  much  larger  in  the  male 
than  in  the  female  is  not  known.  As 
I  hear  from  Mr.  Bate,  the  chelae  are 
sometimes  of  such  length  and  size 
that  they  cannot  possibly  be  used  for 
carrying  food  to  the  mouth.    In  the  males  of  certain  fresh- 

*See  Sir  J.  Lubbock  in  "  Annals  and  Mag.  of  Nat.  Hist.,"  vol.  xi, 
1853,  pi,  i  and  x;  and  vol.  xii,  1853,  pi.  vii.  See  also  Lubbock  in 
"Transact.  Ent.  Soc,"  vol  iv,  new  series,  1853-1858,  p.  8.  With 
respect  to  the  zigzagged  antennae  mentioned  below,  see  Fritz  Milller, 
•'  I'acts  and  Arguments  for  Darwin,"  1869,  p.  40,  foot  note. 


Fig.  4. 


Labidocera  Darwinii 
(from  Lubbock). 


a.  Part  of  right  anterior  an- 

tenna of  male,  forming  a 
prehensile  organ. 

b.  Posterior  pair  of  thoracio 

legs  of  male. 

c.  Ditto  of  female. 


302 


THE  DESCENT  OF  MAN, 


water  prawns  (Palaemon)  the  right  leg  is  actually  longer  than 
the  whole  body.*  The  great  size  of  the  one  leg  witli  its 
chelse  may  aid  Vue  male  in  fighting  with  his  rivals;  but  this 


Fig.  5.  Anterior  part  of  body  of  Callianassa  (from  Milne-Edwards), 
showing  the  unequal  and  differently-constructed  riglr  and 
left  hand  chelae  or  the  male. 

N.  B.— The  artist  by  mistake  has  reversed  the  drawing,  and  made  the 
left-hand  chela  the  largest. 


Fig.  6.  Fig.  7. 

Second  leg  of  male  Orchestia  Tucuratinga  (from  Fritz  Muller). 


Fig.  6.    ^_.  .. 

Fig.  7.    Ditto  of  female 


will  not  account  for  their  inequality  in  the  female  on  the 
opposite  sides  of  the  body.     In  Gelasimus,  according  to  a 

*See  a  paper  by  Mr.  C.  Spence  Bate,  with  figures  in  "  Proc. 
Zoolog.  Soc,"  1868,  p.  363;  and  on  the  nomenclature  of  the  genus, 
ibid,  p.  585.  I  am  greatly  indebted  to  Mr.  Spence  Bate  for  nearly  all 
the  above  statements  with  respect  to  the  chelje  of  the  higher 
crustaceans, 


CBUSTAGEANS.  303 

statement  quoted  by  Milne-Edwards,  *  the  male  and  the 
female  live  in  the  same  burrow,  and  this  shows  that  they 
pair;  the  male  closes  the  mouth  of  the  burrow  with  one  of 
its  chela?,  which  is  enormously  developed;  so  that  here  it 
indirectly  serves  as  a  means  of  defense.  Their  main  use, 
however,  is  probably  to  seize  and  to  secure  the  female,  and 
this  in  some  instances,  as  with  Gammarus,  is  known  to  be 
the  case.  The  male  of  the  hermit  or  soldier  crab  {Pagurni<) 
for  weeks  together,  carries  about  the  shell  inhabited  by  the 
female,  t  The  sexes,  however,  of  the  common  shore-crab 
(Carcinus  m(Bnas),  as  Mr.  Bate  informs  me,  unite  directly 
after  the  female  has  moulted  her  hard  shell,  when  she  is  so 
soft  that  she  would  be  injured  if  seized  by  the  strong 
pincers  of  the  male;  but  as  she  is  caught  and  carried  about 
by  the  male  before  moulting,  she  could  then  be  seized  with 
impunity. 

Fritz  Miiller  states  that  certain  species  of  Melita  are  dis- 
tinguished from  all  other  amphipods  by  the  females  having 
'*  the  coxal  lamellae  of  the  penultimate  pair  of  feet  pro- 
duced into  hook-like  processes,  of  w  hich  the  males  lay  hold 
with  the  hands  of  the  first  pair."  The  development  of 
these  hook-like  processes  has  probably  followed  from  those 
females  which  were  the  most  securely  held  during  the  act 
of  reproduction,  having  left  the  largest  number  of  offspring. 
Another  Brazilian  amphipod  {Orchestia  Darwinii,  fig.  8) 
presents  a  case  of  dimorphism,  like  that  of  Tanais;  for 
there  are  two  male  forms,  which  differ  in  the  stnic- 
ture  of  their  chelae.  J  As  either  chela  would  certainly  suf- 
fice to  hold  the  female — for  both  are  now  used  for  this  pur- 
pose— the  two  male  forms  probably  originated  by  some 
having  varied  in  one  manner  and  some  in  another ; 
both  forms  having  derived  certain  special,  but  nearly  equal 
advantages,  from  their  differently  shaped  organs. 

It  is  not  known  that  male  crustaceans  fight  together  for 
the  possession  of  the  females,  but  it  is  probably  the  case  ; 
for  with  most  animals  when  the  male  is  larger  than  the 
female,  he  seems  to  owe  his  greater  size  to  his  ancestors 

*"  Hist.  Nat.  des  Crust.,"  torn,  ii,  1837,  p.  50. 

f  Mr.  C.  Spence  Bate,  "  Brit.  Assoc,  Fourth  Report  on  tlie  Fauna 
of  S.  Devon." 

^ Fritz  Muller,  "Facts  and  Arguments  for  Darwin,"  1869,  pp. 
^28, 


304  THI£  DESCENT  OF  MAN. 

having  fought  with  other  males  during  many  generations^. 
In  most  of  the  orders,  especially  in  the  highest  or  the 
Brachyura,  the  male  is  larger  than  the  female  ;  the  para- 
sitic genera,  however,  in  which  the  sexes  follow  different 


Fig.  8.    Orchestia  Darwiiiii  (from  Fi-itz  Muller),  showintr  the  differently- 
constructed  chelaj  of  the  two  male  forms. 

hahits  of  life,  and  most  of  the  Entomostraca"  must  be 
excepted.  The  chelae  of  many  crustaceans  are  weapons 
well  adapted  for  fighting.  Thus  when  a  devil-crab  (Por- 
tunus  piiber)  was  seen  by  a  son  of  Mr.  Bate  fighting  with 
a  Carcinus  mcenas,  the  latter  was  soon  thrown  on  its  back, 
and  had   every  limb  torn  from  its  body.     When  several 


CRUSTACEANS.  305 

males  of  a  Brazilian  Gelasimus,  a  species  furnished  with 
immense  pincers,  were  placed  together  in  a  glass  vessel  by 
Fritz  Miiller,  they  mutilated  and  killed  one  another.  Mr. 
Bate  put  a  large  male  Caret  fins  mcenas  into  a  pan  of 
water,  inhabited  by  a  female  which  was  paired  with  a 
smaller  male;  but  the  latter  was  soon  dispossessed.  Mr. 
Bate  adds,  ''  if  they  fought,  the  victory  was  a  bloodless 
one,  for  I  saw  no  wounds."  This  same  naturalist  separated 
a  male  sand-skipper  (so  common  on  our  sea-shores),  Gam- 
marus  marinus,  from  its  female,  both  of  whom  were 
imprisoned  in  the  same  vessel  with  many  individuals  of  the 
same  species.  The  female,  when  thus  divorced,  soon 
joined  the  others.  After  a  time  the  male  was  put  again 
into  the  same  veseel;  and  he  then,  after  swimming  about 
for  a  time,  dashed  into  the  crowd,  and  without  any  fighting 
at  once  took  away  his  wife.  This  fact  shows  that  in  the 
Amphipoda,  an  order  low  in  the  scale,  the  males  and 
females  recognize  each  other  and  are  mutually  attached. 

The  mental  powers  of  the  Crustacea  are  probably  higher 
than  at  first  sight  appears  probable.  Any  one  who  tries  to 
catch  one  of  the  shore-crabs,  so  common  on  tropical  coasts, 
will  perceive  how  wary  and  alert  they  are.  There  is  a  large 
crab  {Birgus  latro),  found  on  coral  islands,  which  makes  a 
thick  bed  of  the  picked  fibers  of  the  cocoanut,  at  the 
bottom  of  a  deep  burrow.  It  feeds  on  the  fallen  fruit  of 
this  tree  by  tearing  off  the  husk,  fiber  by  fiber;  and  it 
always  begins  at  that  end  where  the  three  eye-like  depres- 
sions are  situated.  It  then  breaks  through  one  of  these 
eyes  by  hammering  with  its  heavy  front  pincers,  and,  turn- 
ing round,  extracts  the  albuminous  core  with  its  narrow 
posterior  pincers.  But  these  actions  are  probably  instinct- 
ive, so  that  they  would  be  performed  as  well  by  a  young 
animal  as  by  an  old  one.  The  following  case,  however, 
can  hardly  be  so  considered:  a  trustworthy  naturalist,  Mr. 
Gardner,*  while  watching  a  shore-crab  (Gelasimus)  making 
its  burrow,  threw  some  shells  toward  the  hole.  One  rolled 
in,  and  three  other  shells  remained  within  a  few  inches  of 
the  mouth.  In  about  five  minutes  the  crab  brought  out 
the  shell  which  had  fallen  in,  and  carried  it  away  to  a  dis- 

*"  Travels  in  the  Interior  of  Brazil."  1846,  p.  111.  I  have  given  in 
my  "Journal  of  Researches,"  p.  463,  an  account  of  the  habits  of  the 
Birgus. 


306  THE  DESCENT  OF  MAN. 

tance  of  a  foot;  it  then  saw  the  three  other  shells  lying 
near,  and,  evidently  thinking  that  they  might  likewise  roll 
in,  carried  them  to  the  spot  where  it  had  laid  the  first.  It 
would,  I  think,  be  difficult  to  distinguish  this  act  from  one 
performed  by  man  by  the  aid  of  reason. 

Mr.  Bate  does  not  know  of  any  well-marked  case  of  dif- 
ference of  color  in  the  two  sexes  of  our  British  crustaceans, 
in  which  respect  the  sexes  of  the  higher  animals  so  often 
differ.  In  some  cases,  however,  the  males  and  females  differ 
slightly  in  tint,  but  Mr.  Bate  thinks  not  more  than  may  be 
accounted  for  by  their  different  habits  of  life;  such  as  by 
the  male  wandering  more  about,  and  being  thus  more 
exposed  to  the  light.  Dr.  Power  tried  to  distinguish  by 
color  the  sexes  of  the  several  species  which  inhabit  the 
Mauritius  but  failed,  except  with  one  species  of  Squilla, 
probably  8.  styUfera,  the  male  of  which  is  described  as 
being  "of  a  beautiful  bluish-green,^^  with  some  of  the 
appendages  cherry-red,  while  the  female  is  clouded  with 
brown  and  gray,  *^  with  the  red  about  her  much  less  vivid 
than  in  the  male."*  In  this  case  we  may  suspect  the 
agency  of  sexual  selection.  From  M.  Berths  observation  on 
Daphnia,  when  placed  in  a  vessel  illuminated  by  a  prism, 
we  have  reason  to  believe  that  even  the  lowest  crustaceans 
<3an  distinguish  colors.  AVith  Saphirina  (an  oceanic  genus 
of  Entomostraca),  the  males  are  furnished  with  minute 
shields  or  cell-like  bodies,  which  exhibit  beautiful  changing 
colors;  these  are  absent  in  the  females,  and  in  both  sexes 
of  one  species.  \  It  would,  however,  be  extremely  rash  to 
conclude  that  these  curious  organs  serve  to  attract  the 
females.  I  am  informed  by  Fritz  Miiller,  that  in  the 
female  of  a  Brazilian  species  of  Gelasimus  the  whole  body 
is  of  a  nearly  uniform  grayish-brown.  In  the  male  the 
posterior  part  of  the  cephalo- thorax  is  pure  white,  with  the 
anterior  part  of  a  rich  green,  shading  into  dark  brown;  and 
it  is  remarkable  that  these  colors  are  liable  to  change  in  the 
course  of  a  few  minutes — the  white  becoming  dirty  gray  or 
even  black,  the  green  "  losing  much  of  its  brilliancy."  It 
deserves  especial  notice  that  the  males  do  not  acquire  their 
bright  colors  until  they  become  mature.     They  appear  to 

*Mr.    Ch.  Eraser,   in  "  Proc.  Zoolog.    Soc,"  1869,    p.    3.     I  am 
indebted  to  Mr.  Bate  for  Dr.  Power's  statement, 
f  Claus,  "Die  freilebenden  Copepoden,"  1863,  s.  35, 


SPIDERS.  307 

be  much  more  numerous  than  the  females;  they  differ  also 
in  the  larger  size  of  their  chelae.  In  some  species  of  the 
genus,  probably  in  all,  the  sexes  pair  and  inhabit  the  same 
burrow.  They  are  also,  as  we  have  seen,  highly  intelligent 
animals.  From  these  various  considerations  it  seems  proba- 
ble that  the  male  in  this  species  has  become  gayly  orna- 
mented in  order  to  attract  or  excite  the  female. 

It  has  just  been  stated  that  the  male  Gelasimus  does  not 
acquire  his  conspicuous  colors  until  mature  and  nearly 
ready  to  breed.  This  seems  a  geneml  rule  in  the  whole 
class  in  respect  to  the  many  remarkable  structural  differ- 
ences between  the  sexes.  We  shall  hereafter  find  the  same 
law  prevailing  throughout  the  great  sub-kingdom  of  the 
vert^bi-at^;  and  in  all  cases  it  is  eminently  distinctive  of 
characters  which  have  been  acquired  through  sexual  selec- 
tion. Fritz  Muller  *  gives  some  striking  instances  of  this 
law;  thus  the  male  sand-hopper  (Orchestia)  does  not,  until 
nearly  full  grown,  acquire  his  large  claspers,  which  are 
very  differently  constructed  from  those  of  the  female;  while 
young  his  claspers  resemble  those  of  the  female. 

Archnida  (Spiders). — The  sexes  do  not  generally 
differ  much  in  color,  but  the  males  are  often  darker  than 
the  females,  as  may  be  seen  in  Mr.  BlackwalFs  magnificent 
work.f  In  some  species,  however,  the  difference  is  con- 
spicuous ;  thus  the  female  of  Sparassus  smaragdulus  is 
dullish  green,  while  the  adult  male  has  the  abdomen  of  a  fine 
yellow,  with  three  longitundinal  stripes  of  rich  red.  In 
certain  species  of  Thomisus  the  sexes  closely  resemble  each 
other,  in  others  they  differ  much;  and  analogous  cases  occur 
in  many  other  genera.  It  is  often  difficult  to  say  which  of 
the  two  sexes  departs  most  from  the  ordinary  coloration  of 
the  genus  to  which  the  species  belong;  but  Mr.  Blackwall 
thinks  that,  as  a  general  rule,  it  is  the  male;  and  CanastriniJ 
remarks  that  in  certain  genera  the  males  can  be  specifically 
distinguished  with  ease,  but  the  females  with  great  difficulty. 

*  "  Facts  and  Arguments,"  etc.,  p,  79. 

t  '♦  A  History  of  the  Spiders  of  Great  Britain,"  1861-64.  For  the 
following  facts,  see  pp.  77.  88,  102. 

J  This  author  has  recently  published  a  valuable  essay  on  the 
"Caratteri  sessuali  secondarii  degli  Arachnidi,"  in  the  "  Atti  della 
Soc.  Veneto-Trentina  di  Sc.  Nat.  Padova,"  vol.  i,  Fasc.  3,  1873. 


308  THE  DESCENT  OF  MAN. 

I  am  informed  by  Mr.  Black  wall  that  the  sexes  while  young 
usually  resemble  each  other;  and  both  often  undergo  great 
changes  in  color  during  their  successive  moults  before 
arriving  at  maturity.  In  other  cases  the  male  alone  appears  to 
change  color.  Thus  the  male  of  the  above  bright-colored 
Sparassus  at  iirst  resembles  the  female,  and  acquires  his  pecu- 
liar tints  only  when  nearly  adult.  Spiders  are  possessed  of 
acute  senses,  and  exhibit  much  intelligence;  as  is  well 
known,  the  females  often  show  the  strongest  affection  for 
their  eggs,  which  they  carry  about  enveloped  in  a  silken 
wed.  The  males  search  eagerly  for  the  females,  and  have 
been  seen  by  Canestrini  and  others  to  fight  for  possession  of 
them.  This  same  author  says  that  the  union  of  the  two 
sexes  has  been  observed  in  about  twenty  species;  and  he 
asserts  positively  that  the  female  rejects  some  of  the  males 
who  court  her,  threatens  them  with  open  mandibles 
and  at  last  after  long  hesitation  accepts  the  chosen  one. 
From  these  several  considerations,  we  may  admit  with  some 
confidence  that  the  well-marked  differences  in  color  between 
the  sexes  of  certain  species  are  the  results  of  sexual  selection, 
though  we  have  not  here  the  best  kind  of  evidence — the 
display  by  the  male  of  his  ornaments.  From  the  extreme 
variability  of  color  in  the  male  of  some  species,  for  instance 
of  Theridion  lineatimi,  it  would  appear  that  these  sexual 
characters  of  the  males  have  not  as  yet  become  well  fixed. 
Canestrini  draws  the  same  conclusion  from  the  fact  that  the 
males  of  certain  species  present  two  forms,  differing  from 
each  other  in  the  size  and  length  of  their  Jaws;  and  this 
reminds  us  of  the  above  cases  of  dimorphic  crustaceans. 

The  male  is  generally  much  smaller  than  the  female, 
sometimes  to  an  extraordinary  degree,*  and  he  is  forced  to 
be  extremely  cautious  in  making  his  advances,  as  the 
female  often  carries  her  coyness  to  a  dangerous  pitch. 
De  Geer  saw  a  male  that  "  in  the  midst  of  his  preparatory 
caresses  was  seized  by  the  object  of  his  attentions,  envel- 
oped by  her  in  a  web  and  then  devoured,  a  sight  which,  as 

*  Aug.  Vinson  ("  Araneides  des  lies  de  la  Reunion,"  pi.  vi,  figs.  1 
and  2)  gives  a  good  instance  of  the  small  size  of  the  male,  in  Epeira 
nigra.  In  this  species,  as  I  may  add,  the  male  is  testaceous  and  the 
female  black  with  legs  banded  with  red.  Other  even  more  striking 
cases  of  inequality  in  size  between  the  sexes  have  been  recorded 
("  Quarterly  Journal  of  Science,"  1868,  July,  p.  429);  but  I  have  not 
seen  the  original  accounts. 


JSPIDSM  §09 

he  adds,  filled  him  with  horror  and  indignation/'*  The  Rev. 
0.  P.  Cambridget  accounts  in  the  following  manner  for 
the  extreme  smallness  of  the  male  in  the  genus  Nephila: 
^'  M.  Vinson  gives  a  graphic  account  of  the  agile  way  in 
which  the  diminutive  male  escapes  from  the  ferocity  of  the 
female  by  gliding  about  and  playing  hide  and  seek  over 
her  body  and  along  her  gigantic  limbs.  In  such  a  pursuit 
it  is  evident  that  the  chances  of  escape  would  be  in  favor 
of  the  smallest  males,  while  the  larger  ones  would  fall 
early  victims;  thus  gradually  a  diminutive  race  of  males 
would  be  selected,  until  at  last  they  would  dwindle  to  the 
smallest  possible  size  compatible  with  the  exercise  of  their 
generative  functions — in  fact,  probaby  to  the  size  we  now 
see  them,  i.  e.,  so  small  as  to  be  a  sort  of  parasite  upon  the 
female,  and  either  beneath  her  notice  or  too  agile  and  too 
small  for  her  to  catch  without  great  difficulty." 

Westring  has  made  the  interesting  discovery  that  the 
males  of  several  species  of  TheridionJ;  have  the  power  of 
making  a  stridulating  sound,  while  the  females  are  mute. 
The  apparatus  consists  of  a  serrated  ridge  at  the  base  of 
the  abdomen,  against  which  the  hard  hinder  part  of  the 
thorax  is  rubbed;  and  of  this  structure  not  a  trace  can  be 
detected  in  the  females.  It  deserves  notice  that  several 
writers,  including  the  well  known  arachnologist  AValck- 
enaer,  have  declared  that  spiders  are  attracted  by 
music.  §  From  the  analogy  of  the  Orthoptera  and  Homop- 
tera,  to  be  described  in  the  next  chapter,  we  may  feel 
almost  sure  that  the  stridulation  serves,  as  Westring  also 
believes,  to  call  or  to  excite  the  female;  and  this  is  the  first 
case  known  to  me  in  the  ascending  scale  of  the  animal 
kingdom  of  sounds  emitted  for  this  purpose.  || 

*  Kirby  and  Spence,  "Introduction  to  Entomology,"  vol.  i,  1818, 
p.  280. 

t  "  Proc.  Zoolog.  Soc,"  1871,  p.  621. 

X  TheHdion  {Amgena,  ^iind. )  serratipes,  4-punctatnm  et  guttatum; 
see.  Westring,  in  Krover,  "  Naturbist,  Tidskrift,"  vol.  iv,  1842-1848, 
p.  349;  and  vol.  ii,  1846-1849,  p.  342.  See,  also,  for  otber  sj^ecies, 
"  Araneae  Suecicae,"  p.  184. 

§Dr.  H.  II.  van  Zouteveen,  in  bis  Dutcb  translation  of  this  work 
(vol.  i,  p.  444),  has  collected  several  cases. 

I  Hilgendorf,  however,  has  lately  called  attention  to  an  analogous 
structure  in  some  of  the  higher  crustaceans,  which  seems  adapted  to 
produce  sound;  see  "Zoological  Record,"  1869,  p.  603. 


310  TUS!  DESCUiNT  OF  MAN. 

Myriapoda. — In  neither  of  the  two  orders  in  this  class, 
the  millipedes  and  centipedes,  can  I  find  any  well-marked 
instances  of  such  sexual  differences  as  more  particularly 
concern  us.  In  Glomeris  limhata,  however,  and  perhaps 
in  some  few  other  species,  the  males  differ  slightly  in  color 
from  the  females;  but  this  Glomeris  is  a  highly  variable 
species.  In  the  males  of  the  Diplopoda,  the  legs  belong- 
ing either  to  one  of  the  anterior  or  of  the  posterior  seg- 
ments of  the  body  are  modified  into  prehensile  hooks 
which  serve  to  secure  the  female.  In  some  species  of 
lulus  the  tarsi  of  the  male  are  furnished  with  membranous 
suckers  for  the  same  purpose.  As  we  shall  see  when  we 
treat  of  insects,  it  is  a  much  more  unusual  circumstance, 
that  it  is  the  female  in  Lithobius,  which  is  furnished  with 
prehensile  appendages  at  the  extremity  of  her  body  for 
holding  the  male.* 

*Walckenaer  et  P.  Gervais,  "Hist.  Nat.  des  Insectes;  Apteres," 
torn,  iv,  1847,  pp.  17,  19,  68. 


msECTS,  311 


CHAPTER  X. 

SECONDARY   SEXUAL  CHARACTERS  OF  IKSECTS. 

Diversified  structures  possessed  by  the  males  for  seizLo^  the  females 
— Differences  between  the  sexes,  of  which  the  meaning  is  not 
understood — Difference  in  size  between  the  sexes — Thysanura 
— Diptera — Hemiptera — Homoptera,  musical  powers  possessed 
by  the  males  alone  —  Orthoptera,  musical  instruments  of  the 
males,  much  diversified  in  structure;  pugnacity;  colors — Neu- 
roptera,  sexual  differences  in  color — Hymenoptera,  pugnacity 
and  colors  —  Coleoptera,  colors ;  furnished  with  great  horns, 
apparently  as  an  ornament;  battles;  stridulating  organs  gener- 
ally common  to  both  sexes. 

lis  the  immense  class  of  insects  the  sexes  sometimes 
differ  in  their  locomotive-organs,  and  often  in  their  sense- 
organs,  as  in  the  pectinated  and  beautifully  plumose  anten- 
nae of  the  males  of  many  species.  In  Chloeon,  one  of  the 
Ephemerae,  the  male  has  great  pillared  eyes,  of  which  the 
female  is  entirely  destitute*  The  ocelli  are  absent  in  the 
females  of  certain  insects,  as  in  the  Mutillidae;  and  here  the 
females  are  likewise  wingless.  But  we  are  chiefly  concerned 
with  structures  by  which  one  male  is  enabled  to  conquer 
another,  either  in  battle  or  courtship,  through  his  strength, 
pugnacity,  ornaments,  or  music.  The  innumerable  contriv- 
ances, therefore,  by  which  the  male  is  able  to  seize  the 
female,  may  be  briefly  passed  over.  Besides  the  complex 
structures  at  the  apex  of  the  abdomen,  which  ought  per- 
haps be  ranked  as  primary  organs, f  '*  it  is  astonishing,"  as 

*Sir  J.  Lubbock,  "Transact.  Linnean  Soc.,"  vol.  xxv,  1866,  p. 
484.  With  respect  to  the  Mutillidae  see  VVestwood,  "  Modem  Class, 
of  Insects,"  vol.  ii,  p.  213. 

f  These  organs  in  the  male  often  differ  in  closely  allied  sx)ecies 
and  afford  excellent  si)ecific  characters.  But  their  importance,  from 
a  functional  point  of  view,  as  Mr.  R.  MacLachlan  has  remarked  to 
me,  has  probably  been  overrated.  It  ha.s  been  suggested  that  slight 
differences  in  thc^se  organs  would  suffice  to  prevent  the  intercrossing 
of  well-marked  varieties  or  incipient  species,  and  would  thus  aid  in 


312 


TBE  DESCENT  OF  MAN. 


Mr.  B.  D.  Walsh*  has  remarked,  ^Miow  many  different 
organs  are  worked  in  by  nature  for  the  seemingly  insignifi- 
cant object  of  enabling  the  male  to  grasp  the  female 
firmly/'  The  mandibles  or  jaws  are  sometimes  used  for 
this  purpose;  thus  the  male  Corydalis  corniitus  (a  neu- 
ropterous  insect  in  some  degree  allied  to  the  dragon  flies, 

etc.)  has  immense  curved  jaws, 
many  times  longer  than  those  of 
the  female;  and  they  are  smooth 
instead  of  being  toothed,  so  that 
he  is  thus  enabled  to  seize  her 
without  injury,  f  One  of  the 
stag-beetles  of  North  America 
(Lucanus  elaphus)  uses  his  jaws, 
which  are  much  larger  than 
those  of  the  female,  for  the  same 
purpose  but  probably  likewise 
for  fighting.  In  one  of  the  sand- 
wasps  {AmmopMla)  the  jaws  in 
the  two  sexes  are  closely  alike, 
but  are  used  for  widely  different 
purposes;  the  males,  as  Prof. 
Westwood  observes,  ^^  are  exceed- 
ingly ardent,  seizing  their  part- 
ners round  the  neck  with  their 
sickle-shaped  jaws;''I  while  the 
females  use  these  organs  for 
burrowing  in  sand-banks  and 
making  their  nests. 
The  tarsi  of  the  front  legs  are  dilated  in  many  male 
beetles,  or  are  furnished  with  broad  cushions  of  hair;  and 
in  many  genera  of   water  beetles  they  are  armed  with  a 

their  development.  That  this  can  hardly  be  the  case,  we  may  infer 
from  the  many  recorded  cases  (see,  for  instance,  Bronn,  "  Geschichte 
der  Natur,"  13.  ii,  1843,  s.  164;  and  Westwood,  "  Transact.  Ent. 
Sf>c.,"  vol.  iii,  1842,  p.  195)  of  distinct  species  having  been  observed 
in  union.  Mr.  MacLachlan  informs  me  (vide  "  Stett.  Ent.  Zeitung," 
1867,  s.  155)  that  when  several  species  of  Phryganidae,  which  present 
strongly  pronounced  differences  of  tliis  kind,  were  confined  together 
by  Ur.  Aug.  Meyer,  they  coupled,  and  one  pair  produced  fertile  ova. 

*"  The  Practical  Entomologist,"  Phila.,  vol.   ii.  May,  1867,  p.  88. 

f  Mr.  Walsh,  ibid,  p.  107. 

i  "  Modern  Classification  of  Insects,"  vol.  ii,  1840,  pp.  205.  206. 
Mr.  Walsh,  who  called  my  attention  to  the  double  use  of  the  jaws, 
says  that  lie  has  repeatedly  observed  this  fact. 


Fig.  9.    Crabro  cribrarius.    Upper 
figure  male;  lower  figure  female. 


INSECTS. 


313 


round  flat  sucker,  so  that  the  male  may 
adhere  to  the  slippery  bod\^  of  the  female. 
It  is  a  much  more  unusual  circumstance 
that  the  females  of  some  water  beetles  (l)ytis- 
cus)  have  their  elytra  deeply  grooved,  and  in 
Acilius  sulcatus  thickly  set  with  hairs  as  an 
aid  to  the  male.  The  females  of  some  other 
water  beetles  (Hydroporus)  have  their  elytra 
punctured  for  the  same  purpose.*  In  the 
male  of  C'rabro  cribrarius  (fig.  9)  it  is  the 
tibia  which  is  dilated  into  a  broad  horny 
plate  with  minute  membraneous  dots,  giving 
to  it  a  singular  appearance  like  that  of  a 
riddle,  f  In  the  male  of  Pen  the  (a  genus 
of  beetles)  a  few  of  the  middle  Joints  of  the 
antennae  are  dilated  and  furnished  on  the 
inferior  surface  with  cushions  of  hair,  ex- 
actly like  those  on  the  tarsi  of  the  Carabidae, 
*'and  obviously  for  the  same  end."  In 
male  dragon-flies,  "the  appendages  at  the 
tip  of  the  tail  are  modified  in  an  almost  in- 
finite variety  of  curious  patterns  to  enable 
them  to  embrace  the  neck  of  the  female." 
Lastly,  in  the  males  of  many  insects,  the 
legs  are  furnished  with  peculiar  spines,  knobs 
or  spurs;  or  the  whole  leg  is  bowed  or  thick- 
ened, but  this  is  by  no  means  invariably  a 
sexual  character;  or  one  pair,  or  all  three 
pairs  are  elongated,  sometimes  to  an  extrava- 
gant length.  J 

The  sexes  of  many  species  in  all  the  orders 
present  differences,  of  which  the  meaning  is 
not    understood.       One     curious    case    is 


Fig.  10.  Taphro- 
deres  distortus 
(enlarged).  Up- 
per figure,  male; 
lower  figure, 
female. 


*  We  have  here  a  curious  and  inexpdicable  ca.««  of  dimorphism,  for 
some  of  the  females  of  four  European  species  of  Dysticus,  and  of 
certain  species  of  Hydroporus,  have  their  elytra  smooth;  and  no 
intermediate  gradations  between  the  sulcated  or  punctured,  and  the 
quite  .smooth  elytra  have  been  observed.  See  Dr.  H.  Schaum,  as 
quoted  in  the  "Zoologist,"  vols,  v-vi,  1847-48,  p.  1896.  Also  Kirby 
and  Spence,  "Introduction  to  Entomology,"  vol,  iii,  1826,  p.  305. 

f  Westwood,  "Modern  Cla.ss.,"  vol.  ii,  p.  193.  The  following 
statement  about  Penthe,  and  otliers  in  inverted  commas,  are  taken 
from  Mr.   Walsh,  "Practical  Entomologist,"  Phila.,  vol,  iii,  p.  88. 

:|:  Kirby  and  Spence,  "Introduct.,"  et< .    vol.  iii,  pp.  332-336. 


314  THE  DESCENT  OF  MAM, 

tliat  of  tlie  beetle  (fig.  10),  the  male  of  which  has 
left  mandible  much  enlarged,  so  that  the  mouth  is 
greatly  distorted.  In  another  Carabidous  beetle,  Euryg- 
nathus,*  we  have  the  case,  unique  as  far  as  known  to  Mr. 
Wollaston,  of  the  head  of  the  female  being  much  broader 
and  larger,  though  in  a  variable  degree,  than  that  of  the 
male.  Any  number  of  such  cases  could  be  given.  They 
abound  in  the  Lepidoptera;  one  of  the  most  extraordinary 
is  that  certain  male  butterflies  have  their  fore  legs  more  or 
less  atrophied,  with  the  tibias  and  tarsi  reduced  to  mere 
rudimentary  knobs.  The  wings,  also,  in  the  two  sexes 
often  differ  in  neuration,f  and  sometimes  considerably  in 
outline,  as  in  the  Aricoris  epitus,  which  was  shown  to  me 
in  the  British  Museum  by  Mr.  A.  "Butler.  The  males  of 
certain  South  American  butterflies  have  tufts  of  hair  on 
the  margins  of  the  wings  and  horny  excrescences  on  the 
disks  of  the  posterior  pair.;]:  In  several  British  butterflies, 
as  shown  by  Mr.  Wonfor,  the  males  alone  are  in  parts 
clothed  with  peculiar  scales. 

The  use  of  the  bright  light  of  the  female  glow-worm  has 
been  subject  to  much  discussion.  The  male  is  feebly 
luminous,  as  are  the  larvae  and  even  the  eggs.  ^  It  has  been 
supposed  by  some  authors  that  the  light  serves  to  frighten 
away  enemies,  and  by  others  to  guide  the  male  to  the 
female.  At  last  Mr.  Belt  §  appears  to  have  solved  the 
difficulty;  he  finds  that  all  the  Lampyridae  which  he  has 
tried  are  highly  distasteful  to  insectivorous  mammals  and 
birds.  Hence  it  is  in  accordance  with  Mr.  Bates'  view, 
hereafter  to  be  explained,  that  many  insects  mimic  the 
Lampyridae  closely,  in  order  to  be  mistaken  for  them,  and 
thus  to  escape  destruction.  He  further  believes  that  the 
luminous   species  profit  by   being  at  once   recognized   as 

*  "■  Insecta  Madereusia,"  1854,  p.  20. 

f  E.  Doubleday,  "  Annals  and  Mag.  of  Nat.  Hist.,"  vol.  i,  1848,  p. 
379,  I  may  add  that  the  wings  in  certain  Hymenoptera  (see  Sliuck- 
ard,  "  Fossorial  Hymenop.,"  1837,  pp.  39-43)  differ  in  neuration 
according  to  sex. 

:{:  H.  W.  Bates,  in  "Journal  of  Proc.  Linn.  Soc,"  vol.  vi,  1862,  p. 
74.  Mr.  Wonfor's  observations  are  quoted  in  "Popular  Science 
Eeview,"  1868,  p  343. 

§  "  The  Naturalist  in  Nicaragua,"  1874,  pp.  316-320.  On  the  phos- 
phorescence of  the  eggs,  see  "Annals  and  Mag.  of  Nat.  Hist.,"  1871, 
Nov.,  p.  373. 


unpalatable.  It  is  probable  that  the  same  explanation  may 
be  extended  to  the  Elaters,  both  sexes  of  which  are  highly 
luminous.  It  is  not  known  why  the  wings  of  the  female 
glow-worm  have  not  been  developed;  but  in  her  present 
state  she  closely  resembles  a  larva,  and,  as  larvae  are  so 
largely  preyed  on  by  many  animals,  we  can  understand  why 
she  has  been  rendered  so  much  more  luminous  and  con- 
spicuous than  the  male;  and  why  the  larvae  themselves  are 
likewise  luminous. 

t^Difference  in  Size  Between  the  Sexes. — With  insects  of 
all  kinds  the  males  are  commonly  smaller  than  the  females; 
and  this  difference  can  often  be  detected,  even  in  the  larval 
state.  So  considerable  is  the  difference  between  the  male 
and  female  cocoons  of  the  silk-moth  {Bomhyx  mori),  that 
in  Fmnce  they  are  separated  by  a  particular  mode  of 
weighing.*  In  the  lower  classes  of  the  animal  kingdom 
the  gi-eater  size  of  the  females  seems  generally  to  depend 
on  their  developing  an  enormous  number  of  ova;  and  this 
may  to  a  certain  extent  hold  good  with  insects.  But  Dr. 
Wallace  has  suggested  a  much  more  probable  explanation. 
He  finds,  after  carefully  attending  to  the  development  of 
the  caterpillars  of  Bomhyx  cynthia  and  yamamai,  and  espe- 
cially to  that  of  some  dwarfed  caterpillars  reared  from  a 
second  brood  on  unnatural  food,  'Hhat  in  proportion  as 
the  individual  moth  is  finer,  so  is  the  time  required  for  its 
metamorphosis  longer;  and  for  this  reason  the  female,  which 
is  the  larger  and  heavier  insect,  from  having  to  caiTy  her 
numerous  eggs,  will  be  preceded  by  the  male,  which  is 
smaller  and  has  less  to  mature.^f  Xow  as  most  insects  are 
short-lived,  and  as  they  are  exposed  to  many  dangers,  it 
would  manifestly  be  advantageous  to  the  female  to  be  im- 
pregnated as  soon  as  possible.  This  end  would  be  gained 
by  the  males  being  first  matured  in  large  numbers  ready  for 
the  advent  of  the  females;  and  this  again  would  naturally 
follow,  as  Mr.  A.  R.  Wallace  has  remarked, J  through  nat- 
ural selection;  for  the  smaller  males  would  be  first  matured, 
and  thus  would  procreate  a  large  number  of  offspring  which 
would  inherit  the  reduced  size  of  their  male  parents,  while 

*Rc>binet,  "Vers  a  Soie,"  1848,  p.  207. 

f  "  Transact.  Ent.  Soc.,"  3d  series,  vol.  v,  p.  486. 

X  "  Journal  of  Proc.  Ent.  Soc,"  Feb.  4,  1867,  p.  71. 


316  THE  DESCENT  OF  MAN. 

the  larger  males,  from  being  matured  later,  would  leave 
fewer  offspring^ 

There  are,  however,  exceptions  to  the  rule  of  male  insects 
being  smaller  than  the  females;  and  some  of  these  exceptions 
are  intelligible.  Size  and  strength  would  be  an  advantage 
to  the  males,  which  fight  for  the  possession  of  the  females; 
and  in  these  cases,  as  with  the  stag-beetle  (Lucanus),  the 
males  are  larger  than  the  females.  There  are,  however, 
other  beetles  wliich  are  not  known  to  fight  together,  of  which 
the  males  exceed  the  females  in  size;  and  the  meaning  of  this 
fact  is  not  known;  but  in  some  of  these  cases,  as  with  the 
huge  Dynastes  and  Megasoma,  we  can  at  least  see  that  there 
would  be  no  necessity  for  the  males  to  be  smaller  than  the 
females,  in  order  to  be  matured  before  them,  for  these 
beetles  are  not  short-lived,  and  there  would  be  ample  time 
for  the  pairing  of  the  sexes.  So  again,  male  dragon-flies 
(Libellulid£e)  are  sometimes  sensibly  larger,  and  never 
smaller,  than  the  females;*  and,  as  Mr.  MacLachlan  believes, 
they  do  not  generally  pair  with  the  females  until  a  week  or 
fortnight  has  elapsed,  and  until  they  have  assumed  their 
proper  masculine  colors.  But  the  most  curious  case  show- 
ing on  what  complex  and  easily  overlooked  relations  so 
trifling  a  character  as  difference  in  size  between  the  sexes 
may  depend,  is  that  of  the  aculeate  Hymenoptera;  for  Mr. 
F.  Smith  informs  me  that  throughout  nearly  the  whole  of 
this  large  group,  the  males,  in  accordance  with  the  general 
rule,  are  smaller  than  the  females,  and  emerge  about  a 
week  before  them;  but  among  the  bees,  the  males  of  Apis 
mellificay  Anthidium  7)ia)iicatum,  and  AntJiopliora  acervo- 
rum,  and  among  the  Fossores  the  males  of  the  Metliora 
ichneumonid<is  are  larger  than  the  females.  The  explana- 
tion of  this  anomaly  is  that  a  marriage  flight  is  absolutely 
necessary  with  these  species,  and  the  male  requires  great 
strength  and  size  in  order  to  carry  the  female  through  the 
air.  Increased  size  has  here  been  acquired  in  opposition  to 
the  usual  relation  between  size  and  the  period  of  develop- 
ment, for  the  males,  though  larger,  emerge  before  the 
smaller  females. 

We  will  now  review  the  several  orders,  selecting  such 
facts  as  more  particularly  concern  us.     The   Lepidoptera 

*  For  tins  and  otber  statements  on  the  size  of  the  sexes,  see  Kirby 
and  Spence,  ibid.,  vol.  iii,  p.  300;  on  the  duration  of  life  in  insects, 
see  p.  344. 


INSECTS.  317 

(butterflies    and    moths)  will  be  retained   for  a  separate 
chapter. 

TJiysanura. — The  members  of  this  lowly  organized 
order  are  wingless,  dull-colored,  minute  insects,  with  ugly, 
almost  misshapen  heads  and  bodies.  Their  sexes  do  not 
differ,  but  they  are  interesting  as  showing  us  that  the  males 
pay  sedulous  court  to  the  females  even  low  down  in  the  ani- 
mal scale.  Sir  J.  Lubbock*  says:  ''it  is  very  amusing  to 
see  these  little  creatures  {Srnynthurus  htfeiis)  coquetting 
together.  The  male,  which  is  much  smaller  than  the 
female,  runs  round  her,  and  they  butt  one  another,  stand- 
ing face  to  face  and  moving  backward  and  forward  like  two 
playful  lambs.  Then  the  female  pretends  to  run  away  and 
the  male  runs  after  her  with  a  queer  appearance  of  anger, 
gets  in  front  and  stands  facing  her  again;  then  she  turns 
coyly  round,  but  he,  quicker  and  more  active,  scuttles 
round  too,  and  seems  to  whip  her  with  his  antennae;  then 
for  a  bit  they  stand  face  to  face,  play  with  their  antennae, 
and  seem  to  be  all  in  all  to  one  another." 

Diptera  (Flies). — The  sexes  differ  little  in  color.  The 
greatest  difference,  known  to  Mr.  F.  Walker,  is  in  the 
genus  Bibio,  in  which  the  males  are  blackish  or  quite 
black,  and  the  females  obscure  brownish-orange.  The 
genus  Elaphomyia,  discovered  by  Mr.  Wallace  \  in  New 
Guinea,  is  highly  remarkable,  as  the  males  are  furnished 
with  horns,  of  which  the  females  are  quite  destitute.  The 
horns  spring  from  beneath  the  eyes,  and  curiously  resemble 
those  of  a  stag,  being  either  branched  or  palmated.  In  one 
of  the  species,  they  equal  the  whole  body  in  length.  They 
might  be  thought  to  be  adapted  for  fighting,  but  as  in  one 
species  they  are  of  a  beautiful  pink  color,  edged  with  black, 
with  a  pale  central  stripe,  and  as  these  insects  have  alto- 
gether a  very  elegant  appearance  it  is  perhaps  more  proba- 
ble that  they  serve  as  ornaments.  That  the  males  of  some 
Diptera  fight  together  is  certain;  Prof.  WestwoodJ;  has 
several  times  seen  this  with  the  Tipulae.  The  males  of 
other  Diptera  apparently  try  to  win  the  females  by  their 

♦"Transact.  Linnean  Soc,"  vol.  xxvi,  1868,  p.  296. 
t  "  The  Malay  Archipelago."  vol.  ii,  1869,  p.  313. 
|"Modera  Classitioation  of  Insects/'  vol.  ii.  1840.  p.  536. 


318  THE  DESCENT  OF  MAN. 

music.  H.  Muller*  watched  for  some  time  two  males  of  an 
Eristalis  courting  a  female;  they  hovered  above  her,  and 
flew  from  side  to  side  making  a  high  humming  noise  at  the 
same  time.  Gnats  and  mosquitoes  (Culicida^)  also  seem  to 
attract  each  other  by  humming ;  and  Prof.  Mayer  has 
recently  ascertained  that  the  hairs  on  the  antennae  of  the 
male  vibrate  in  unison  with  the  notes  of  a  tuning-fork 
within  the  range  of  the  sounds  emitted  by  the  female.  The 
longer  hairs  vibrate  sympathetically  with  the  graver  notes, 
and  the  shorter  hairs  with  the  higher  ones.  Landois  also 
asserts  that  he  has  repeatedly  drawn  down  a  whole  swarm 
of  gnats  by  uttering  a  particular  note.  It  may  be  added 
that  the  mental  faculties  of  the  Diptera  are  probably  higher 
than  in  most  other  insects,  in  accordance  with  their  highly 
developed  nervous  system,  f 

Hemiptera  (Field  Bugs). — Mr.  J.  W.  Douglas,  who  has 
particularly  attended  to  the  British  species,  has  kindly 
given  me  an  account  of  their  sexual  differences.  The 
males  of  some  species  are  furnished  with  wings,  while  the 
females  are  wingless;  the  sexes  differ  in  the  form  of  their 
bodies,  elytra,  antennae  and  tarsi;  but  as  the  signification  of 
these  differences  is  unknown  they  may  be  here  passed  over. 
The  females  are  generally  larger  and  more  robust  than  the 
males.  With  British  and,  as  far  as  Mr.  Douglas  knows, 
with  exotic  species  the  sexes  do  not  commonly  differ  much 
in  color;  but  in  about  six  British  species  the  male  is  con- 
siderably darker  than  the  female,  and  in  about  four  other 
species  the  female  is  darker  than  the  male.  Both  sexes  of 
some  species  are  beautifully  colored;  and  as  these  insects 
emit  an  extremely  nauseous  odor  their  conspicuous  colors 
may  serve  as  a  signal  that  they  are  unpalatable  to  insect- 
ivorous animals.  In  some  few  cases  their  colors  appear  to 
be  directly  protective  ;  thus  Prof.  Hoffmann  informs  me. 
that  he  could  hardly  distinguish  a  small  pink  and  green 
species  from  the  buds  on  the  trunks  of  lime-trees  which 
this  insect  frequents. 

*Anwendung,  etc.,  "Verb.  d.  n.  V.  Jahrg.,"  xxix,  p.  80.  Mayer, 
in  "American  Naturalist,"  1874,  p.  236. 

f  See  Mr.  B.  T.  Lowne's  interesting  work,  *'  On  the  Anatomy  of  the 
Blow-fly,  Musca  vomitoria,"  1870,  p.  14.  He  remarks  (p.  83)  that 
"  the  captured  flies  utter  a  peculiar  plaintive  note,  and  that  this 
sound  causes  other  flies  to  disappear," 


INSECTS.  319 

Some  species  of  Keduvidge  make  a  stridulating  noise;  and 
in  the  case  of  Pirates  sfriduhis  this  is  said*  to  be  effected 
by  the  movement  of  the  neck  within  the  pro-thoracic 
cavity.  According  to  Westring,  Becliivius  personatus  also 
stridulates.  But  I  have  no  reason  to  suppose  that  this  is  a 
sexual  character,  excepting  that  with  non-social  insects 
there  seems  to  be  no  use  for  sound-producing  organs  unless 
it  be  as  a  sexual  call. 

Homoptera. — Every  one  who  has  wandered  in  a  tropi- 
cal forest  must  have  been  astonished  at  the  din  made 
by  the  male  Cicadae.  The  females  are  mute ;  as  the 
Grecian  poet  Xenarchus  says:  ^'  Happy  the  Cicadas  live, 
since  they  all  have  voiceless  wives."  The  noise  thus  made 
could  be  plainly  heard  on  board  the  "  Beagle/'  when 
anchored  at  a  quarter  of  a  mile  from  the  shore  of  Brazil; 
and  Capt.  Hancock  says  it  can  be  heard  at  the  distance  of  a 
mile.  The  Greeks  formerly  kept,  and  the  Chinese  now 
keep,  these  insects  in  cages  for  the  sake  of  their  song,  so 
that  it  must  be  pleasing  to  the  ears  of  some  men.f  The 
Cicadidae  usually  sing  during  the  day,  while  the  FulgoridaB 
appear  to  be  night-songsters.  The  sound,  according  to 
Landois,J  is  produced  by  the  vibration  of  the  lips  of  the 
spiracles,  which  are  set  in  motion  by  a  current  of  air 
emitted  from  the  trachae;  but  this  view  has  lately  been  dis- 
puted. Dr.  Powell  appears  to  have  proved  §  that  it  is  pro- 
duced by  the  vibration  of  a  membrane  set  into  action  by  a 
special  muscle.  In  the  living  insect,  while  stridulating, 
this  membrane  can  be  seen,  to  vibrate;  and  in  the  dead 
insect  the  proper  sound  is  heard,  if  the  muscle,  when  a  little 
dried  and  hardened,  is  pulled  with  the  point  of  a  pin.  In 
the  female  the  whole  complex  musical  apparatus  is  present, 
but  is  much  less  developed  than  in  the  male,  and  is  never 
used  for  producing  sound. 

With  respect  to  the  object  of  the  music.  Dr.  Hartman,  in 
speaking  of  the  Cicada  septemdecim  of  the  United  States, 

*  Westvvood,  "Modern  Class,  of  Insects,"  vol.  ii,  p.  473. 

f  These  particulars  are  taken  from  West  wood's  "  Modern  Class,  of 
Insects,"  vol.  ii,  1840,  p.  422.  See  also,  on  the  Fulgoridae,  Kirby 
and  Spence,  "  Introduct. ,"  vol.  ii,  p.  401. 

X  "Zeitschrift  fiir  wissenschaft  Zoolog.,"  B.  xvii,  1867,  ss.  152-158, 
§  "Transact.  New  Zealand  Institute,"  vol.  v,  1873,  p.  286, 


320  THE  DESCENT  OF  MAN. 

says,*  ^^tlie  drums  are  now  (June  6  and  7,  1851)  heard  in 
all  directions.  This  I  believe  to  be  the  marital  summons 
from  the  males.  Standing  in  thick  chestnut  sprouts  about 
as  high  as  my  head,  where  hundreds  were  around  me,  I 
observed  the  females  coming  around  the  drumming  males." 
He  adds,  "this  season  (August,  1868)  a  dwarf  pear-tree  in 
my  garden  produced  about  fifty  larvae  of  Cic.  pruinosa;  and 
I  several  times  noticed  the  females  to  alight  near  a  male 
while  he  was  uttering  his  clanging  notes."  Fritz  Miiller 
writes  to  me  from  S.  Brazil  that  he  has  often  listened  to  a 
musical  contest  between  two  or  three  males  of  a  species 
with  a  particularly  loud  voice,  seated  at  a  considerable  dis- 
tance from  each  other;  as  soon  as  one  had  finished  his  song 
another  immediately  began  and  then  another.  As  there  is 
so  much  rivalry  between  the  males,  it  is  probable  that  the 
females  not  only  find  them  by  their  sounds,  but  that,  like 
female  birds,  they  are  excited  or  allured  by  the  male  with 
the  most  attractive  voice. 

I  have  not  heard  of  any  well-marked  cases  of  ornamental 
differences  between  the  sexes  of  the  Homoptera.  Mr. 
Douglas  informs  me  that  there  are  three  British  species,  in 
which  the  male  is  black  or  marked  with  black  bands,  while 
the  females  are  pale-colored  or  obscure. 

\Qrthoptera  (Crickets  and  Grasshoppers). — The  males  in 
the  three  saltatorial  families  in  this  order  are  remarkable 
for  their  musical  powers,  namely  the  Achetidae  or  crickets, 
the  Locustidae,  for  which  there  is  no  equivalent  English 
name,  and  the  Acridiidae  or  grasshoppers.  The  stridula- 
tion  produced  by  some  of  the  Locustidae  is  so  loud  that 
it  can  be  heard  during  the  night  at  the  distance  of  a 
mile;t  and  that  made  by  certain  species  is  not  unmusical 
even  to  the  human  ear,  so  that  the  Indians  on  the  Amazons 
keep  them  in  wicker  cages.  All  observers  agree  that  the 
sounds  serve  either  to  call  or  excite  the  mute  females. 
With  respect  to  the  migratory  locusts  of  Kussia,  Korte  has 
given  I  an  interesting  case  of  selection  by  the  female  of  a 

*  I  am  indebted  to  Mr.  Walsh  for  having  sent  me  this  extract  from 
a  "  Journal  of  the  Doings  of  Cicada  septemdecim,"  by  Dr.  Hartman. 

f  L.  Guilding,  "  Transact.  Linn.  Soc,"  vol.  xv,  p.  154. 

X I  state  this  on  the  authority  of  Koppen,  "  Ueber  die  Heuschrecken 
in  Slidrussland,"  1866,  p.  32,  for  I  have  in  vain  endeavored  to  pro- 
cure Korte's  work. 


INSECTS. 


321 


male.  The  males  of  this  species  {Pachytyliis  migratorius) 
while  coupled  with  the  female  stridulate  from  anger  or 
jealousy  if  approached  by  other  males.  The  house-cricket 
when  surprised  at  night  uses  its  voice  to  warn  its  fellows. 'Q 
In  North  America  the  Katydid  {Ptatyphyllum  concavum, 
one  of  the  Locustidae)  is  described  f  as  mounting  on  the 
upi>er  branches  of  a  tree,  and  in  the  evening  beginning 
**his  noisy  babble,  while  rival  notes  issue  from  the  neigh- 
boring ti-ees,  and  the  groves  resound  with  the  call  of 
Katy  -  did  -  she  -  did  the  live- 
long night."  Mr.  Bates,  in 
speaking  of  the  European 
field-cricket  (one  of  the  Ache- 
tidae),  says  ^^the  male  has  been 
observed  to  place  himself  in 
the  evening  at  the  entrance 
of  his  burrow,  and  stridulate 
until  a  female  approaches, 
when  the  louder  notes  are 
succeeded  by  a  more  subdued 
tone,  while  the  successful 
musician  caresses  with  his 
antennae  the  mate  he  has 
won.  "J  Dr.  Scudder  was  able 
to  excite  one  of  these  insects 
to  answer  him,  by  rubbing  on 
a  file  with  a  quill.  §  In  both 
sexes  a  remarkable  auditory 
apparatus  has  been  discovered 
by  Von  Siebold,  situated  in  the  front  legs.  || 

In  the  three  families  the  sounds  are  differently  produced. 
In  the  males  of  the  Achetidae  both  wing-covers  have  the 
same  apparatus;  and  this  in  the  field-cricket  (Gryllus 
campestris,  fig.   11)  consists,  as  described  by  Landois,!^  of 

♦Gilbert  White,  "  Nat.  Hist,  of  Selborne,"  vol.  ii,  1825,  p.  262. 

f  Harris,  "  Insects  of  New  England,"  1842,  p.  128. 

X"  The  Naturalist  on  the  Amazons,"  vol.  i.  1863,  p.  252.  Mr. 
Bates  gives  a  very  interesting  discussion  on  tlie  gradations  in  the 
musical  apparatus  of  the  three  families.  See  also  Westwood,  ' '  Mod- 
ern Class.,"  vol.  ii,  pp.  445,  453. 

§  "  Proc.  Boston  Soc.  of  Nat.  Hist.,"  vol.  xi,  April,  1868. 

(  "  Nouveau  Manuel  d'Anat.  Comp."  (French  translat.),  torn,  i, 
1850,  p.  567. 

1"  Zeitschrift  fur  wissenschaft.  Zoolog.,"  B.  xvii,  1867,  s.  117. 


Fig. 


11.  Gryllus  campestris  (from 
Landois). 
Right-hand  figure,  under  side  of  part 
of  a  wing-nervure,  much  magnified, 
showing  the  teeth,  st. 
Left-hand  figure,  upper  surface  of 
wing-cover,  with  the  projecting, 
smooth  nervure,  r,  across  which  the 
teeth  {st)  are  scraped. 


32-3  THE  DESCENT  OF  MAN. 

from  131  to  138  sharp,  transverse  ridges  or  teeth  {st)  on 
the  under  side  of  one  of  the  nervures  of  the  wing-cover. 
This  toothed  nervure  is  rapidly  scraped  across  a  projecting, 
smooth,  hard  nervure  (r)  on  the  upper  surface  of  the  oppo- 
site wing.  First  one  wing  is  rubbed  over  the  other,  and 
then  the  movement  is  reversed.  Both  wings  are  raised  a 
little  at  the  same  time,  so  as  to  increase  the  resonance.  In 
some  species  the  wing-covers  of  the  males  are  furnished  at 
the  base  with  a  talc-like  plate.*  I  here  give  a  drawing 
(fig.  12)  of  the  teeth  on  the  under  side  of  the  nervure  of 
another  species  of  Gryllus,  viz.,  G.  domesticus.  With 
respect  to  the  formation  of  these  teeth.  Dr.  Gruber  has 
shown  t  that  they  have  been  developed  by  the  aid  of 
-_^  selection,  from  the  minute  scales  and  hairs 
with  which  the  wings  and  body  are  covered, 
and  I  came  to  the  same  conclusion  with 
respect  to  those  of  the  Ooleoptera.  But  Dr. 
Gruber  further  shows  that  their  development 
is  in  part  directly  due  to  the  stimulus  from 
the  friction  of  one  wing  over  the  other. 

In  the  Locustidae  the  opposite  wing-covers 

differ  from  each  other  in  structure  (fig  13), 

^Nerv'iire  of  Gryi-  ^^^^  ^^®  action  cannot,  as  in  the  last  family, 

1  u  s  domesticus  be  reversed.    The  left  wing,  which  acts  as  the 

(from  Landois).    |^^^^  j-^^  ^^^^  ^j^^^  right  wing  which  serves  as 

the  fiddle.  One  of  the  nervures  (a)  on  the  under  surface  of 
the  former  is  finely  serrated,  and  is  scraped  across  the 
prominent  nervures  on  the  upper  surface  of  the  opposite  or 
right  wing.  In  our  British  Fhasgonura  viridissima  it 
appears  to  me  that  the  serrated  nervure  is  rubbed  against 
the  rounded  hind-corner  of  the  opposite  wing,  the  edge  of 
which  is  thickened,  colored  brow^n,  and  very  sharp.  In 
the  right  wing,  but  not  in  the  left,  there  is  a  little  plate,  as 
transparent  as  talc,  surrounded  by  nervures,  and  called  the 
speculum.  In  EpMppiger  vitium,  a  member  of  this  same 
family,  we  have  a  curious  subordinate  modification;  for  the 
\ving-cover&  are  greatly  reduced  in  size,  but  ''  the  posterior 
part  of  the  pro-thorax  is  elevated  into  a  kind  of  dome  over 

*  Westwood,  "  Modern  Class,  of  Insects,"  vol.  i,  p.  440. 
f  "  Ueber  der  Tonapparat  der  Locustiden,  ein  Beitrag  zum  Darwin- 
ismus,"  "ZeitscU.  fiir  wissenscb   Zoolog.,"  B.  xxii,  1872,  p.  100, 


INSECTS.  323 

the   wing-covers,  and   which   has    probably   the   effect  of 
increasing  the  sound."* 

We  thus  see  that  the  musical  apparatus  is  more  dif- 
ferentiated or  specialized  in  the  Locustidae  (which 
include,  I  believe,   the    most    powerful    performers    in 


Fig.  13.  Chloroccelus  Tanana  (from  Bates),  a,  h.  Lobes  of  opposite  wing-covers. 

the  order),  and  in  the  Achetidae,  in  which  both  wing- 
covers  have  the  same  structure  and  the  same  function,  f 
Landois,  however,  detected  in  one  of  the  Locustidae, 
namely  in  Decticus,  a  short  and  narrow  row  of  small 
teeth,  mere  rudiments,  on  the  inferior  surface  of  the 
right  wing-cover,  which  underlies  the  other  and  is  never 
used  as  the  bow.  I  observed  the  same  rudimentary 
structure  on  the  under  side  of  the  right  wing- 
cover  in  Phasgonura  viridissima.  Hence  we  may  infer 
with  confidence  that  the  Locustidae  are  descended  from  a 
form  in  which,  as  in  the  existing  Achetidae,  both  wing- 

*Westwood,  "Modern  Class,  of  Insects,"  vol.  i,  p.  453. 

t  Landois,  "  Zeitsch.  f.  wiss  Zoolog."  B.  xvii,  1867,  ss.  121,  122. 


324 


THE  DESCENT  OF  MAN. 


covers  had  serrated  nerviires  on  the  under  surface  and  could 
be  indifferently  used  as  the  bow;  but  that  in  the  Locustidae 
the  two  wing-covers  gradually  became  differentiated  and 
perfected  on  the  principle  of  the  division  of  labor,  the  one 
to  act  exclusively  as  the  bow  and  the  other  as  the  fiddle. 
Dr.  Gruber  takes  the  same  view,  and  has  shown  that  rudi- 
mentary teeth  are  commonly  found  on  the  inferior  surface 
of  the  right  wing.  By  what  steps  the  more  simple  appa- 
ratus in  the  Achetidae  originated  we  do  not  know,  but  it  is 
probable  that  the  basal  portions  of  the  wing-covers  origi- 
nally overlapped  each  other  as  they  do  at  present;  and  that 

the  friction  of  the  nervures 
produced  a  grating  sound  as 
is  now  the  case  with  the  wing- 
covers  of  the  females.*  A 
grating  sound  thus  occasion- 
ally and  accidentally  made  by 
the  males,if  it  served  them  ever 
so  little  as  a  love-call  to  the  fe- 
males, might  readily  have  been 
intensified  through  sexual  se- 
lection by  variations  in  the 
roughness  of  the  nervures  hav- 
ing been  continuallypreserved . 
leg  of  stenobothrus  pra-  ^^  ^^e  last  and  third  family, 
the  striduiating  ridge ;  namely,    the    Acridiidae     or 

iwTemSmSn^a'fr?^^^^^  the  stridulation 

is  produced  in  a  very  differ- 
ent manner,  and  according  to  Dr.  Scudder,  is  not  so  shrill 
as  in  the  preceding  families.  The  inner  surface  of  the 
femur  (fig.  14,  r)  is  furnished  with  a  longitudinal  row  of 
minute,  elegant,  lancet-shaped,  elastic  teeth  from  eighty- 
five  to  ninety-three  in  number;!  and  these  are  scraped 
across  the  sharp,  projecting  nervures  on  the  wing-covers 
which  are  thus  made  to  vibrate  and  resound.  Harris^  says 
that  when  one  of  the  males  begins  to  play  he  first  ^'^  bends 
the  shank  of  the  hind-leg  beneath  the  thigh,  where  it  is 

*Mr.  Walsh  also  informs  me  that  he  has  noticed  that  the  female 
of  the  Platyphyllum  concavum,  "  when  captured,  makes  a  feeble 
grating  noise  by  shuffling  her  wing-covers  together." 

f  Landois,  ibid.,  s.  113. 

\  "  Insects  of  New  England,"  1842,  p.  133. 


Fig.  14,  Hind-leg  of  Stenobothrus  pra 
torum.     r 


mSEGTS. 


325 


lodged  in  a  furrow  designed  to  receive  it,  and  then  draws 
the  leg  briskly  up  and  down.  He  does  not  play  both 
fiddles  together,  but  alternately,  first  upon  one  and  then 
on  the  other /^  In  many  species  the  base  of  the  abdomen 
is  hollowed  out  into  a  great  cavity  which  is  believed  to  act 
as  a  resounding  board.     In  Pneumora  (fig.  15),  a  S.  Afri- 


Fig.  15.    Pneumora  (from  specimens  in  the  British  Museum).    Upper 
figure,  male;  lower  figure,  female. 

can  genus  belonging  to  the  same  family,  we  meet  with  a 
new  and  remarkable  modification;  in  the  males  a  small 
notched  ridge  projects  obliquely  from  each  side  of  the 
abdomen,  against  which  the  hind  femora  are  rubbed.*  As 
the  male  is  furnished  with  wings  (the  female  being  wing- 

*  Westwood,  "Modern  Classification,"  vol.  i,  p.  463. 


326  THE  DElSGENT  OF  MAN, 

less)  it  is  remarkable  that  the  thighs  are  not  rubbed  in  the 
usual  manner  against  the  wing-covers;  but  this  may  per- 
haps be  accounted  for  by  the  unusually  small  size  of  the 
hind  legs.  I  have  uot  been  able  to  examine  the  inner  sur- 
face of  the  thighs,  which,  judging  from  analogy,  would  be 
finely  serrated.  The  species  of  Pneumora  have  been  more 
profoundly  modified  for  the  sake  of  stridulation  than  any 
other  orthopterous  insect;  for  in  the  male  the  whole  body 
has  been  converted  into  a  musical  instrument,  being  dis- 
tended with  air  like  a  great  pellucid  bladder  so  as  to 
increase  the  resonance.  Mr.  Trimen  informs  me  that  at 
the  Cape  of  Good  Hope  these  insects  make  a  wonderful 
noise  during  the  night. 

In  the  three  foregoing  families  the  females  are  almost 
always  destitute  of  an  efficient  musical  apparatus.  But  there 
are  a  few  exceptions  to  this  rule,  for  Dr.  Gruber  has  shown 
that  both  sexes  of  Ephippiger  vitiiim  are  thus  provided; 
though  the  organs  diifer  in  the  male  and  female  to  a  cer- 
tain extent.  Hence  we  cannot  suppose  that  they  have  been 
transferred  from  the  male  to  the  female,  as  appears  to  have 
been  the  case  with  the  secondary  sexual  characters  of  many 
other  animals.  They  must  have  been  independently  devel- 
oped in  the  two  sexes,  which  no  doubt  mutually  call  to 
each  other  during  the  season  of  love.  In  most  other  Locus- 
tidae  (but  not  according  to  Landois  in  Decticus)  the  females 
have  rudiments  of  the  stridulatory  organs  proper  to  the 
male;  from  whom  it  is  probable  that  these  have  been  trans- 
ferred. Landois  also  found  such  rudiments  on  the  under 
surface  of  the  wing-covers  of  the  female  Achetidae,  and  on 
the  femora  of  the  female  Acridiidae.  In  the  Homoptera, 
also,  the  females  have  the  proper  musical  apparatus  in  a 
functionless  state;  and  we  shall  hereafter  meet,  in  other 
divisions  of  the  animal  kingdom,  with  many  instances  of 
structures  proper  to  the  male  being  present  in  a  rudimentary 
condition  in  the  female. 

Landois  has  observed  another  important  fact,  namely, 
that  in  the  females  of  the  Acridiidae,  the  stridulating  teeth 
on  the  femora  remain  throughout  life  in  the  same  condition 
in  which  they  first  appear  during  the  larval  state  in  both 
sexes.  In  the  males,  on  the  hand,  they  become  further 
developed,  and  acquire  their  perfect  structure  at  the  last 
moult,  when  the  insect  is  mature  and  ready  to  breed. 
•    From  the  facts  now  given  we   see   that  the  means   by 


INSECTS.  32'}' 

wliich  the  males  of  the  Orthoptera  produce  their  sounds  are 
extremely  diversified,  and  are  altogether  different  from 
those  employed  by  tlie  Homoptera.*  But  throughout  the 
animal  kingdom  we  often  find  the  same  object  gained  by 
the  most  diversified  means;  this  seems  due  to  the  whole 
organization  having  undergone  multifarious  changes  in  the 
course  of  ages,  and  as  part  after  part  varied  different  varia- 
tions v/ere  taken  advantage  of  for  the  same  general  purpose. 
/Jhe  diversity  of  means  for  producing  sound  in  the  three 
families  of  the  Orthoptera  and  in  the  Homoptera, 
impresses  the  mind  with  the  high  importance  of  these 
structures  to  the  males,  for  the  sake  of  calling  or  alluring 
the  femalesTj  We  need  feel  no  surprise  at  the  amount  of 
modification  which  the  Orthoptera  have  undergone  in  this 
respect,  as  we  now  know,  from  Dr.  Scudder's  remarkable 
discovery,  f  that  there  has  been  more  than  ample  time. 
This  naturalist  has  lately  found  a  fossil  insect  in  the 
Devonian  formation  of  New  Brunswick,  which  is  furnished 
with  "  the  well-known  tympanum  or  stridulating  apparatus 
of  the  male  Locustidae."  The  insect,  though  in  most 
respects  related  to  the  Neuroptera,  appears,  as  is  so  often 
the  case  with  very  ancient  forms,  to  connect  the  two  related 
orders  of  the  Neuroptera  and  Orthoptera. 

I  have  but  little  more  to  say  on  the  Orthoptera.  Some 
of  the  species  are  very  pugnacious;  when  two  male  field- 
crickets  (Gryllns  campestris)  are  confined  together  they 
fight  till  one  kills  the  other;  and  the  species  of  Mantis  are 
described  as  maneuvering  with  their  sword-like  front  limbs, 
like  hussars  with  their  sabers.  The  Chinese  keep  these 
insects  in  little  bamboo  cages,  and  match  them  like  game- 
cocks. |  With  respect  to  color,  some  exotic  locusts  are 
beautifully  ornamented;  the  posterior  wings  being  marked 
with  red,  blue  and  black;  but  as  throughout  the  order  the 
sexes  rarely  differ  much  in  color,  it  is  not  probable  that 
they  owe  their  bright  tints  to  sexual  selection.     Conspicu- 

•  Landois  has  recently  found  in  certain  Orthoptera  rudimentary 
structures  closely  similar  to  the  sound-producing  organs  in  the 
Homoptera;  and  this  is  a  surprising  fact.  See  "Zeitschr.  fiir  wis- 
sensch.  Zoolog.,"  B.  xxii,  Heft  3,  1871,  p.  348 

f  "  Transact.  Ent.  Soc,"  3d  series,  vol.  ii.  ("  Journal  of  Proceed- 
ings," p   117.) 

X  West  wood,  "  Modern  Class,  of  Insects,"  vol.  i,  p.  427;  for  crick- 
ets, p.  445. 


328  ^S[S:  DESCENT  OF  MAN, 

ous  colors  may  be  of  use  to  these  insects  by  giving  notice 
that  they  are  unpalatable.  Thus  it  has  been  observed*  that 
a  bright-colored  Indian  locust  was  invariably  rejected  when 
offered  to  birds  and  lizards.  Some  cases,  however,  are 
known  of  sexual  differences  in  color  in  this  order.  The 
male  of  an  American  cricket  f  is  described  as  being  as 
white  as  ivory,  while  the  female  varies  from  almost  white  to 
greenish-yellow  or  dusky.  Mr.  Walsh  informs  me  that  the 
adult  male  of  Spectrum  femoratum  (one  of  the  Phasmidas) 
"is  of  a  shining  brownish-yellow  color;  the  adult  female 
being  of  a  dull,  opaque,  cinereous  brown;  the  young  of 
both  sexes  being  green."  Lastly,  I  may  mention  that  the 
male  of  one  curious  kind  of  cricket  J  is  furnished  with  ''a 
long  membranous  appendage,  which  falls  over  the  face  like 
a  vail;"  but  what  its  use  may  be  is  not  known. 

Neuroptera. — Little  need  here  be  said,  except  as  to  color. 
In  the  Ephemeridse  the  sexes  of  ten  differ  slightly  in  their 
obscure  tints ;§  but  it  is  not  probable  that  the  males  are 
thus  rendered  attractive  to  the  females.  The  Libellulidae 
or  dragon-flies,  are  ornamented  with  splendid  green,  blue, 
yellow,  and  vermilion  metalic  tints ;  and  the  sexes  often 
differ.  Thus,  as  Prof.  Westwood  remarks,  ||  the  males 
of  some  of  the  Agrionidae,  "'^are  of  a  rich  blue  with  black 
wings,  while  the  females  are  fine  green  with  colorless 
wings."  But  in  Agrion  Eamburii  these  colors  are  exactly 
reversed  in  the  two  sexes.  ^  In  the  extensive  North  Ameri- 
can genus  of  Hetaerina,  the  males  alone  have  a  beautiful 
carmine  spot  at  the  base  of  each  wing.  In  Anax  Junius 
the  basal  part  of  the  abdomen  in  the  male  is  a  vivid  ultra- 
marine blue,  and  in  the  female  grass-green.  In  the  allied 
genus  Gomphus,  on  the  other  hand,  and  in  some  other 
genera,  the  sexes  differ  but  little  in  color.    In  closely-allied 

*Mr.  Cli.  Home,  in  "Proc.  Ent.  Soc,"  May  3,  1869,  p.  12. 

f  The  (Ecanthus  nivalis.  Harris,  "  Insects  of  New  England,"  1842, 
p.  124.  The  two  sexes  of  the  ffi'.  pellucidus  of  Europe  differ,  as  I 
liear  from  Victor  Cams,  in  nearly  the  same  manner. 

if  Platyblemnus;  Westwood,  "Modern  Class.,"  vol.  i,  p.  447. 

^  B.  D.  Walsh,  the  "  Pseudoneuroptera  of  Illinois,"  in  "  Proc.  Ent. 
Soc.  of  Philadelphia,"  1862,  p.  361. 

II  "  Modern  Class.,"  vol.  ii,  p.  37. 

1  Walsh,  ibid.,  p.  381.  I  am  indebted  to  this  naturalist  for  the  fol- 
lowing facts  on  Hetaerina,  Anax  and  Gomphus. 


INSECTS.  329 

forms  throughout  the  animal  kingdom  similar  cases  of  the 
sexes  differing  greatly,  or  very  little,  or  not  at  all,  are  of 
frequent  occurrence.  Although  there  is  so  wide  a  differ- 
ence in  color  between  the  sexes  of  many  Libellulidae,  it  is 
often  difficult  to  say  which  is  the  more  brilliant;  and  the 
ordinary  coloration  of  the  two  sexes  is  reversed,  as  we  have 
just  seen,  in  one  species  of  Agrion.  It  is  not  probable  that 
their  colors  in  any  case  have  been  gained  as  a  protection. 
Mr.  MacLachlan,  who  has  closely  attended  to  this  family, 
Avrites  to  me  that  dragon-flies — the  tyrants  of  the  insect- 
world — are  the  least  liable  of  any  insect  to  be  attacked  by 
birds  or  other  enemies,  and  he  believes  that  their  bright 
colors  serve  as  a  sexual  attraction.  Certain  dragon-flies 
apparently  are  attracted  by  particular  colors;  Mr.  Patterson 
observed*  that  the  Agrionidffi,  of  which  the  males  are  blue, 
settled  in  numbers  on  the  blue  float  of  a  fishing  line;  while 
two  other  species  were  attracted  by  shining  white  colors. 

It  is  an  interesting  fact,  first  noticed  by  Schelver,  that, 
in  several  genera  belonging  to  two  sub-families,  the  males 
on  first  emergence  from  the  pupal  state,  are  colored  exactly 
like  the  females ;  but  that  their  bodies  in  a  short  time 
assume  a  conspicuous  milky-blue  tint,  owing  to  the  exuda- 
tion of  a  kind  of  oil,  soluble  in  ether  and  alcohol.  Mr. 
MacLachlan  believes  that  in  the  male  of  LiMlula  depressa 
this  change  of  color  does  not  occur  until  nearly  a  fortnight 
after  the  metamorphosis,  when  the  sexes  are  ready  to  pair. 

Certain  species  of  Neurothemis  present,  according  to 
Brauer,f  a  curious  case  of  dimorphism,  some  of  the 
females  having  ordinary  wings,  while  others  have  them 
"  very  richly  netted,  as  in  the  males  of  the  same  species.^" 
Brauer  "explains  the  phenomenon  on  Darwinian  principles 
by  the  supposition  that  the  close  netting  of  the  veins  is  a 
secondary  sexual  character  in  the  males,  which  has  been 
abruptly  transferred  to  some  of  the  females,  instead  of,  as 
generally  occurs,  to  all  of  them.'^  Mr.  MacLachlan 
informs  me  of  another  instance  of  dimorphism  in  sev- 
eral species  of  Agrion,  in  which  some  individuals  are 
of  an  orange  color,  and  these  are  invariably  females. 
This  is  probably  a  case  of  reversion ;  for  in  the 
true  Libellulae,  when  the  sexes  differ  in  color,  the  females 

♦"Transact.  Ent.  Soc,"  vol.  i,  1836,  p.  81. 

f  See  abstract  in  the  "Zoological  Kecord  "  for  1867,  p.  450. 


330  THE  DE8GWNT  OF  MAN. 

are  orange  or  yellow;  so  that  supposing  Agrion  to  be 
descended  from  some  primordial  form  which  resembled  the 
typical  Libullulae  in  its  sexual  characters,  it  would  not  be 
surprising  that  a  tendency  to  vary  in  this  manner  should 
occur  in  the  females  alone. 

Although  many  dragon-flies  are  large,  powerful  and  fierce 
insects,  the  males  have  not  been  observed  by  Mr.  Mac- 
Lachlan  to  fight  together,  excepting,  as  he  believes,  in  some 
of  the  smaller  species  of  Agrion.  In  another  group  in  this 
order,  namely,  the  Termites  or  white  ants,  both  sexes  at 
the  time  of  swarming  may  be  seen  running  about,  ^*^the 
male  after  the  female,  sometimes  two  chasing  one  female, 
and  contending  with  great  eagerness  who  shall  win  the 
prize.^^*  The  Atropos  palsatorius  is  said  to  make  a  noise 
with  its  jaws,  which  is  answered  by  other  individuals.  \ 

Hypienoptera. — That  inimitable  observer,  M.  Fabre,!  in 
describing  the  habits  of  Cerceris,  a  wasp-like  insect, 
remarks  that  ^'  fights  frequently  ensue  between  the  males 
for  the  possession  of  some  particular  female,  who  sits  an 
apparently  unconcerned  beholder  of  the  struggle  for  suprem- 
acy, and  when  the  victory  is  decided,  quietly  flies  away  in 
company  with  the  conqueror."  Westwood  §  says  that  the 
males  of  one  of  the  saw-flies  (Tenthredina?)  "have  been 
found  fighting  together  with  their  mandibles  locked."  As 
M.  Fabre  speaks  of  the  males  of  Cerceris  striving  to  obtain 
a  particular  female,  it  may  be  well  to  bear  in  mind  that 
insects  belonging  to  this  order  have  the  power  of  recogniz- 
ing each  other  after  long  intervals  of  time,  and  are  deeply 
attached.  For  instance,  Pierre  Huber,  whose  accuracy  no  one 
doubts,  separated  some  ants,  and  when,  after  an  interval  of 
four  months,  they  met  others  which  had  formerly  belonged 
to  the  same  community,  they  recognized  and  caressed  one 
another  with  their  antennae.  Had  they  been  strangers  they 
would  have  fought  together.  Again,  when  two  commu- 
nities engage  in  a  battle  the  ants  on  the  same  side  some- 

*  Kirby  and  Spence,  "  Introduct.  to  Entomology,'*  vol.  ii,  1818, 
p.  35. 

f  Houzeau,  ''  Les  Facultes  Mentales,"  etc.,  torn,  i,  p.  104. 

I  See  an  interesting  article,  "The  Writings  of  Fabre,"  in  "  Nat. 
Hist.  Review,"  April,  1862.  p.  122. 

§  "Journal  of  Proc.  of  Entomolog.  Soc,"  Sept,  7,  1863,  p.  169 


INSECTS.  331 

times  attack  each  other  in  the  general  confusion,  hut  they 
soon  perceive  their  mistake,  and  the  one  ant  soothes  the 
other.  * 

In  this  order  slight  differences  in  color,  according  to  sex, 
are  common,  hut  conspicuous  differences  are  rare  except  in 
the  family  of  bees;  yet  both  sexes  of  certain  gi'oups  are  so 
brilliantly  colored — for  instance  in  Chrysis,  in  which  ver- 
milion and  metallic  greens  prevail — that  we  are  tempted  to 
attribute  the  result  to  sexual  selection.  In  the  Ichneu- 
monidae,  according  to  Mr.  Walsh,  f  the  males  are  almost 
universally  lighter-colored  than  the  females.  On  the  other 
hand,  in  the  Tenthredinidae  the  males  are  generally  darker 
than  the  females.  In  the  Siricidae  the  sexes  frequently 
differ;  thus  the  male  of  Sir  ex  jnvencus  is  banded  with 
orange,  while  the  female  is  dark  purple;  but  it  is  difficult 
to  say  which  sex  is  the  more  ornamented.  In  Tremex 
columhcB  the  female  is  much  brighter  colored  than  the 
male.  I  am  informed  by  Mr.  F.  Smith  that  the  male 
ants  of  several  species  are  black,  the  females  being 
testaceous. 

In  the  family  of  bees,  especially  in  the  solitary  species, 
as  I  hear  from  the  same  entomologist,  the  sexes  often  differ 
in  color.  The  males  are  generally  the  brighter,  and  in 
Bombus  as  well  as  in  Apathus,  much  more  variable  in  color 
than  the  females.  In  Anthopliora  retusa  the  male  is  of  a 
rich  fulvous-brown,  while  the  female  is  quite  black;  so  are 
the  females  of  several  species  of  Xylocopa,  the  males  being 
bright  yellow.  On  the  other  hand  the  females  of  some 
species,  as  of  Andrcena  fulva,  are  much  brighter  colored 
than  the  males.  Such  differences  in  color  can  hardly  be 
accounted  for  by  the  males  being  defenseless  and  thus 
requiring  protection,  w^hile  the  females  are  well  defended 
by  their  stings.  H.  Miiller,];  who  has  particularly  attended 
to  the  habits  of  bees,  attributes  these  differences  in  color  in 
chief  part  to  sexual  selection.  That  bees  have  a  keen  per- 
ception of  color  is  certain.  He  says  that  the  males  search 
eagerly  and  fight  for  the  possession  of  the  females;  and  he 

*P.  Huber,  "  Recherches  sur  les  Moeurs  des  Fourmis,"  1810,  pp. 
150,  165. 

t  '•  Proc.  Entomolog.  Soc.  of  Philadelphia,"  1866,  pp.  238,  239. 

X  "  Anwendung  der  Darwinschen  Lehre  auf  Bienen,"  Verh.  d.  n. 
Jahrg.,  xxix. 


332  THE  DESCENT  OF  MAN. 

accounts  through  such  contests  for  the  mandibles  of  the 
males  being  in  certain  species  larger  than  those  of  the 
females.  In  some  cases  the  males  are  far  more  numerous 
than  the  females,  either  early  in  the  season,  or  at  all  times 
and  places,  or  locally;  whereas  the  females  in  other  cases 
are  apparently  in  excess.  In  some  species  the  more  beauti- 
ful males  appear  to  have  been  selected  by  the  females;  and 
in  others  the  more  beautiful  females  by  the  males.  Conse- 
quently in  certain  genera  (Miiller,  p.  42)  the  males  of  the 
several  species  diifer  much  in  appearance,  while  the  females 
are  almost  indistinguishable;  in  other  genera  the  reverse 
occurs.  H,  Miiller  believes  (p.  82)  that  the  colors  gained 
by  one  sex  through  sexual  selection  have  often  been  trans- 
ferred in  a  variable  degree  to  the  other  sex,  just  as  the' 
pollen-collecting  apparatus  of  the  female  has  often  been 
transferred  to  the  male,  to  whom  it  is  absolutely  useless.* 

Mutilla  Europcea  makes  a  stridulating  noise;  and  accord- 
ing to  Goureau  \  both  sexes  have  this  power.  He  attributes 
the  sound  to  the  friction  of  the  third  and  preceding 
abdominal  segments,  and  I  find  that  these  surfaces  are 
marked  with  very  fine  concentric  ridges;  but  so  is  the  pro- 
jecting thoracic  collar  into  which  the  head  articulates,  and 
this  collar,  when  scratched  with  the  point  of  a  needle, 
emits  the  proper  sound.  It  is  rather  surprising  that  both 
sexes  should  have  the  power  of  stridulating,  as  the  male  is 

*M.  Perrier  in  his  article  *'  la  Selection  sexuelle  d'apres  Darwin" 
("  Revue  Scientifique,"  Feb.,  1873,  p.  868),  without  apparently  having 
reflected  much  on  the  subject,  objects  that  as  the  males  of  social  bees 
are  known  to  be  produced  from  unfertilized  ova,  they  could  not  trans- 
mit new  characters  to  their  male  offspring.  This  is  an  extraordinary 
objection.  A  female  bee  fertilized  by  a  male,  which  presented  some 
character  facilitating  the  union  of  the  sexes,  or  rendering  him  more 
attractive  to  the  female,  would  lay  eggs  which  w^ould  produce  only 
females;  but  these  young  females  would  next  year  produce  males ; 
and  will  it  be  pretended  that  such  males  would  not  inherit  the  char- 
acters of  their  male  grandfathers?  To  take  a  case  with  ordinary  ani- 
mals as  nearly  parallel  as  possible;  if  a  female  of  any  white  quad- 
ruped or  bird  were  crossed  by  a  male  of  a  black  breed,  and  the  male 
and  female  offspring  were  paired  together,  will  it  be  pretended  that 
the  grandchildren  would  not  inherit  a  tendency  to  blackness  from 
their  male  grandfather?  The  acquirement  of  new  characters  by  the 
sterile  worker-bees  is  a  much  more  difficult  case,  but  I  have  endeav- 
ored to  show  in  my  "  Origin  of  Species  "  how  these  sterile  beings  are 
subjected  to  the  power  of  natural  selection. 

f  Quoted  by  Westwood,  "  Modern  Class,  of  Insects,"  vol.  ii,  p.  214 


INSECTS,  333 

winged  and  the  female  wingless.  It  is  notorious  that  bees 
express  certain  emotions,  as  of  anger,  by  the  tone  of  their 
humming;  and  according  to  H.  Mliller  (p.  80)  the  males 
of  some  species  make  a  peculiar  singing  noise  while  pursu- 
ing the  females. 

Coleoptera  (Beetles). — Many  beetles  are  colored  so  as  to 
resemble  the  surfaces  which  they  habitually  frequent,  and 
they  thus  escape  detection  by  their  enemies.  Other  species, 
for  instance  diamond-beetles,  are  ornamented  with  splendid 
colors,  wiiich  are  often  arranged  in  stripes,  spots,  crosses 
and  other  elegant  patterns.  Such  colors  can  hardly  serve 
directly  as  a  protection  except  in  the  case  of  certain  flower- 
feeding  species;  but  they  may  serve  as  a  warning  or  means 
of  recognition  on  the  same  principle  as  the  phosphorescence 
of  the  glow-worm.  As  with  beetles  the  colors  of  the  two 
sexes  are  generally  alike,  we  have  no  evidence  that  they 
have  been  gained  through  sexual  selection;  but  this  is  at 
least  possible,  for  they  may  have  been  developed  in  one  sex 
and  then  transferred  to  the  other;  and  this  view  is  even  in 
some  degree  probable  in  those  groups  which  possess  other 
well-marked  secondary  sexual  characters.  Blind  beetles, 
which  cannot  of  course  behold  each  other^s  beauty,  never, 
as  I  hear  from  Mr.  Waterhouse,  Jr.,  exhibit  bright  colors, 
though  they  often  have  polished  coats;  but  the  explanation 
of  their  obscurity  may  be  that  they  generally  inhabit  caves 
and  other  obscure  stations. 

Some  Longicorns,  especially  certain  Prionidse,  offer  an 
exception  to  the  rule  that  the  sexes  of  beetles  do  not  differ 
in  color.  Most  of  these  insects  are  large  and  splendidly 
colored.     The  males  in  the  genus  Pyrodes,*  which  I  saw 

*  Pyrodes  pulcherrimus,  in  whicli  the  sexes  differ  conspicuously, 
has  been  described  by  Mr.  Bates  in  ''Transact.  Ent.  Soc,"  1869,  p. 
50.  I  will  specify  the  few  other  cases  in  which  I  have  heard  of  a 
difference  in  color  between  the  sexes  of  beetles.  Kirby  and  Spence 
("  Introduct.  to  Entomology,"  vol.  iii,  p.  301)  mention  a  Cantharis, 
Meloe,  Rhagium,  and  the  Leptura  testacea ;  the  male  of  the  latter 
being  testaceous,  with  a  black  thorax,  and  the  female  of  a  dull  red 
all  over.  These  two  latter  beetles  belong  to  the  family  of  Longi- 
corns. Messrs.  R.  Trimen  and  Waterhouse  junior  inform  me  of  two 
Lamellicorns,  viz.,  a  Peritrichia  and  Trichius,  the  male  of  the  latter 
being  more  obscurely  colored  than  the  female.  In  Tillus  elongatus 
the  male  is  black,  and  the  female  always,  as  it  is  believed,  of  a  dark 
blue  color,  with  a  red  thorax.  The  male,  also,  of  Orsodac.ia  atra,  as 
I  hear  from  Mr.  Walsh,  is  black,  the  female  (the  so  called  0.  nijicol- 
lis)  having  a  rufous  horax. 


334 


THE  DESCENT  OF  MAN. 


in  Mr,  Bates'  collection,  are  generally  redder  but  rather 
duller  than  the  females,  the  latter  being  colored  of  a  more 
or  less  splendid  golden-green.  On  the  other  hand,  in  one 
species  the  male  is  golden-green,  the  female  being  richly 
tinted  with  red  and  purple.  In  the  genus  Esmeralda  the 
sexes  differ  so  greatly  in  color  that  they  have  been  ranked 
as  distinct  species;  in  one  species  both  are  of  a  beautiful 
shining  green,  but  the  male  has  a  red  thorax.  On  the 
whole,  as  far  as  I  could  judge,  the  females  of  those 
Prionidae,  in  which  the  sexes  ditfer,  are  colored  more  richly 
than  the  males,  and  this  does  not  accord  with  the  common 
rule  in  regard  to  color  when  acquired  through  sexual 
selection. 

[K  most  remarkable  distinction  between  the  sexes  of  many 
beetles  is  presented  by  the  great  horns  which  rise  from  the 
head,  thorax  and  clypeus  of  the  males;  and  in  some  few 
cases  from  the  under  surface  of  the  body.  These  horns 
in  the  great  family  of  the  Lamellicorns,  resemble  those  of 
various  quadrupeds,  such  as  stags,  rhinoceroses,  etc.,  and 
are  wonderful  both  from  their  size  and  diversified  shapes. 
Instead  of  describing  them,  I  have  given  figures  of  the 
males  and  females  of  some  of  the  more  remarkable  forms. 
(Figs.  16  to  20.)     The  females  generally  exhibit  rudiments 


Fig.  16.    Chalcosoma  atlas. 


Upper  figure,  male  (reduced;:  lower  figure,  female 
(natural  sige). 


INSECTS. 


385 


Fig.  17.  Copris  isidis.    (Left-hand  figures,  males.) 


Fhanaens  faunus. 


Fig.  19. 


Dipelicns  cantori. 


Fig.  30.  Onthophagus  rangifer,  enlarged 


336  THE  DESCENT  OF  MAN. 

of  the  horns  in  the  form  of  small  knobs  or  ridges;  but  some 
are  destitute  of  even  the  slightest  rudiment.^  On  the  other 
hand^  the  horns  are  nearly  as  well  developecHn  the  female 
as  in  the  male  of  Plimiwus  lancifer;  and  only  a  little  less 
well  dev^eloped  in  the  females  of  some  other  species  of  this 
genus  and  of  Copris.  I  am  informed  by  Mr.  Bates  that 
the  horns  do  not  differ  in  any  manner  corresponding  with 
the  more  important  characteristic  differences  between  the 
several  subdivisions  of  the  family;  thus  within  the  same 
section  of  the  genus  Onthophagus,  there  are  species  which 
have  a  single  horn  and  others  which  have  two. 

In  almost  all  cases  the  horns  are  remarkable  from  their 
excessive  variability;  so  that  a  graduated  series  can  be 
formed  from  the  most  highly  developed  males  to  others  so 
degenerate  that  they  can  barely  be  distinguished  from  the 
females.  Mr.  Walsh*  found  that  in  PhaiuBus  carnifex  the 
horns  were  thrice  as  long  in  some  males  as  in  others.  Mr. 
Bates,  after  examining  above  a  hundred  males  of  Ontlio- 
phagus  rangifer  (fig.  20),  thought  that  he  had  at  last  dis- 
covered a  species  in  which  the  horns  did  not  vary;  but 
further  research  proved  the  contrary. 

The  extraordinary  size  of  the  horns  and  their  widely  dif- 
ferent structure  in  closely-allied  forms  indicate  that  they 
have  been  formed  for  some  purpose;  but  their  excessive 
variability  in  the  males  of  the  same  species  leads  to  the 
inference  that  this  purpose  cannot  be  of  a  definite  nature. 
The  horns  do  not  show  marks  of  friction,  as  if  used  for  any 
ordinary  work.  Some  authors  suppose  f  that  as  the  males 
wander  about  much  more  than  the  females,  they  require 
horns  as  a  defense  against  their  enemies;  but  as  the  horns 
are  often  blunt,  they  do  not  seem  well  adapted  for  defense. 
The  most  obvious  conjecture  is  that  they  are  used  by  the 
males  for  fighting  together;  but  the  males  have  never  been 
observed  to  fight;  nor  could  Mr.  Bates,  after  a  careful 
examination  of  numerous  species,  find  any  sufficient  evi- 
dence, in  their  mutilated  or  broken  condition,  of  their 
having  been  thus  used.  If  the  males  had  been  habitual 
fighters,  the  size  of  their  bodies  would  probably  have  been 
increased  through  sexual  selection,  so  as  to  have  exceeded 
that  of  the  females;  but  Mr.  Bates,  after  comparing  the 

*  "Proc.  Entomolog.  Soc.  of  Philadelphia,"  1864,  p.  228. 

f  Kirbj^  and  Spence,  '•  InT^roduct.  Entomolog.,"  vol.  iii,  p.  300. 


INSECTS.  337 

two  sexes  in  above  a  hundred  species  of  the  Copridoe,  did 
not  tind  any  marked  difference  in  this  respect  among  well- 
developed  individuals.  In  Lethrus,  moreover,  a  beetle 
belonging  to  the  same  great  division  of  the  Lamellicoms, 
the  males  are  known  to  fight,  but  are  not  provided  with 
horns,  though  their  mandibles  are  much  larger  than  those  of 
the  female. 

The  conclusion  that  the  horns  have  been  acquired  as 
ornaments  is  that  which  best  agrees  with  the  fact  of  their 
having  been  so  immensely,  yet  not  fixedly,  developed — as 
shown  by  their  extreme  variability  in  the  same  species,  and 
by  their  extreme  diversity  in  closely-allied  species.  This 
view  will  at  first  appear  extremely  improbable;  but  we  shall 


Figr.  21.  Fig.  22. 

Fig.  21.    Onitis  furcifer,  male  viewed  from  beneath. 

Fig.  22.  Left-hand  figure,  male  of  Onitis  furcifer,  viewed  laterally.  Right- 
hand  figure,  female,  a.  Rudiment  of  cephalic  horn.  b.  Trace  of 
thoracic  horn  or  crest. 

hereafter  find  with  many  animals  standing  much  higher  in 
the  scale,  namely  fishes,  amphibians,  reptiles  and  birds, 
that  various  kinds  of  crests,  knobs,  horns  and  combs  have 
been  developed  apparently  for  this  sole  purpose. 

The  males  of  Onith  furcifer  (fig.  21),  and  of  some  other 
species  of  the  genus  are  furnished  with  singular  projections 
on  their  anterior  femora,  and  with  a  great  fork  or  pair  of 
horns  on  the  lower  surface  of  the  thorax.  Judging  from 
other  insects,  these  may  aid  the  male  in  clinging  to  the 
female.  Although  the  males  have  not  even  a  trace  of  a  horn 
on  the  upper  surface  of  the  body,  yet  the  females  plainlv  ex- 
hibit a  rudiment  of  a  single  horn  on  the  head  (fig.  22,  a)  and 
of  a  crest  {h)  on  the  thorax.  That  the  slight  thoracic  crest 
in  the  female  is  a  rudiment  of  a  projection  proper  to  the  male, 
though  entirely  absent  in  the  male  of  this  particular  species, 
is  cl^ar;  for  the  female   of   Bubas.  bison  (a  genus  which 


338  THE  DESCENT  OF  MAN, 

comes  next  to  Onitis)  has  a  similar  slight  crest  on  the 
tliorax,  and  the  male  bears  a  great  projection  in  the  same 
situation.  80,  again,  there  can  hardly  be  a  doubt  that  the 
little  point  (a)  on  the  head  of  the  female  Onitis  furcifer, 
as  well  as  on  the  head  of  the  females  of  two  or  three  allied 
species,  is  a  rudimentary  representative  of  the  cephalic 
horn,  which  is  common  to  the  males  of  so  many  Lamelli- 
corn  beetles,  as  in  Phatiaeus  (fig.  18). 

The  old  belief  that  rudiments  have  been  created  to  com- 
plete the  scheme  of  nature  is  here  so  far  from  holding 
good,  that  we  have  a  complete  inversion  of  the  ordinary 
state  of  things  in  the  family.  We  may  reasonably  suspect 
that  the  males  originally  bore  horns  and  transferred  them 
to  the  females  in  a  rudimentary  condition,  as  in  so  many 
other  Lamellicorns.  Why  the  males  subsequently  lost  their 
horns,  we  know  not;  but  this  may  have  been  caused  through 


f.    ^ 


Fig.  23.  Bledius  taurus,  magnified.    Left-hand  figure,  male;  right-hand  figure, 

female. 

the  principle  of  compensation,  owing  to  the  development  of 
the  large  horns  and  projections  on  the  lower  surface;  and 
as  these  are  confined  to  the  males,  the  rudiments  of  the 
upper  horns  on  the  females  would  not  have  been  thus 
obliterated. 

The  cases  hitherto  given  refer  to  the  Lamellicorns,  but 
the  males  of  some  few  other  beetles,  belonging  to  two 
widely  distinct  groups,  namely,  the  Ourculionidae  and 
Staphylinidae,  are  furnished  with  horns — in  the  former  on 
the  lower  surface  of  the  body,*  in  the  latter  on  the  upper 
surface  of  the  head  and  thorax.  In  the  Staphylinidae,  the 
horns  of  the  males  are  extraordinarily  variable  in  the  same 
species,  just  as  we  have  seen  with  the  Lamellicorns.  In 
Siagonium  we  have  a  case  of  dimorphism,  for  the  males 
can  be  divided  into  two  sects,  differing  greatly  in  the  size 
of  their  bodies  and  in  the  development  of  their  horns,  with- 
out intermediate  gradations.  In  a  species  of  Bledius  (fig. 
23),  also  belonging  to  the  Staphylinidae,  Prof.  Westwood 

*Kirby  and  SpencCj  "Introduct,  Entomolog.,"  vol.  iii,  p.  339, 


INSECTS.  339 

states  that,  '^  male  specimens  can  be  found  in  the  same 
locality  in  which  the  central  horn  of  the  thorax  is  very 
large,  but  the  horns  of  the  head  quite  rudimeiital ;  and 
others,  in  which  the  thoracic  horn  is  much  shorter,  while 
the  protuberances  on  the  head  are  long."*  Here  we  appar-- 
ently  have  a  case  of  compensation,  which  throws  light  on 
that  just  given,  of  the  supposed  loss  of  the  upper  horns  by 
the  males  of  Oriitis. 

Late  of  Battle. — Some  male  beetles,  which  seem  ill-fitted 
for  fighting,  nevertheless  engage  in  conflicts  for  the  posses- 
sion of  the  females.  Mr.  Wallace  f  saw  two  males  of 
Leptorhynchiis  angustatus,  a  linear  beetle  with  a  much 
elongated  rostrum,  ^^  fighting  for  a  female,  who  stood  close 
by  busy  at  her  boring.  They  pushed  at  each  other  with 
their  rostra,  and  clawed  and  thumped,  apparently  in  the 
greatest  rage."  The  smaller  male,  however,  "  soon  ran 
away,  acknowledging  himself  vanquished."  [Jn  some  few 
cases  male  beetles  are  well  adapted  for  fighting,  by  possess- 
ing great  toothed  mandibles,  much  larger  than  those  of  the 
females.  This  is  the  case  with  the  common  stag-beetle 
(Lucanus  cervus),  the  males  of  which  emerge  from  the 
pupal  state  about  a  week  before  the  other  sex,  so  that 
several  may  often  be  seen  pursuing  the  same  female.  At 
this  season  they  engage  in  fierce  conflicts.  When  Mr.  A. 
H.  Davis  X  inclosed  two  males  with  one  female  in  a  box 
the  larger  male  severely  pinched  the  smaller  one  until  he 
resigned  his  pretensions.  A  friend  informs  me  that  when  a 
boy  he  often  put  the  males  together  to  see  them  fight,  and 
he  noticed  that  they  were  much  bolder  and  fiercer  than  the 
females,  as  with  the  higher  animals.  The  males  would 
seize  hold  of  his  finger  if  held  in  front  of  them,  but  not  so 
the  females,  although  they  have  stronger  jaws  J  The  males 
of  many  of  the  Lucanidae,  as  well  as  of  the  above-men- 

*  "Modern  Classification  of  Insects,"  vol.  i,  p.  172;  Siagonium,  p. 
172.  In  the  Britisli  Museum  I  noticed  one  male  specimen  of  Siago- 
nium in  an  intermediate  condition,  so  that  the  dimorphism  is  not 
strict. 

f  **  The  Malay  Archipelago,"  vol.  ii,  1869,  p.  276.  Riley,  Sixth 
"Report  on  Insects  of  Missouri,"  1874,  p.  115. 

X  "  Entomological  Magazine,"  vol.  i,  1833,  p.  82.  See  also  on  the 
conflicts  of  this  species,  Kirby  and  Spence,  ibid.,  vol.  iii,  p.  314;  and 
West  wood,  ibid.,  vol.  i,  p.  187. 


340  THE  DESCENT  OF  MAN, 

tioiied  Leptorhynchus,  are  larger  and  more  powerful  insects 
than  the  females.  The  two  sexes  of  Lethrns  cephalotes 
(one  of  the  Lamellicorns)  inhabit  the  same  burrow;  and 
the  male  has  larger  mandibles  than  the  female.  If,  during 
•the  breeding  season,  a  strange  male  attempts  to  enter  the 
burrow  he  is  attacked;  the  female  does  not  remain  passive, 
but  closes  the  mouth  of  the  burrow,  and  encourages  her 
mate  by  continually  pushing  him  on  from  behind;  and  the 
battle  lasts  until  the  aggressor  is  killed  or  runs  away.*  The 
two  sexes  of  another  Lamellicorn  beetle,  the  Ateuchus 
cicatricosus,  live  in  pairs,  and  seem  much  attached  to  each 
other;  the  male  excites  the  females  to  roll  the  balls  of  dung 
in  which  the  ova  are  deposited;  and  if  she  is  removed  he 
becomes  much  agitated.  If  the  male  is  removed  the 
female  ceases  all  work,  and,  as  M.  Brulerie  \  believes,  would 
remain  on  the  same  spot  until  she  died. 

The  great  mandibles  of  the  male  Lucanidae  are  extremely 
variable  both  in  size  and  structure,  and  in  this  respect 
resemble  the  horns  on  the  head  and  thorax  of  many  male 
Lamellicorns  and  Staphylinidae.  A  perfect  series  can  be 
formed  from  the  best-provided  to  the  worst-provided  or 
degenerate  males.  Although  the  mandibles  of  the  common 
stag-beetle,  and  probably  of  many  other  species,  are  used  as 
efficient  weapons  for  fighting,  it  is  doubtful  whether  their 
great  size  can  thus  be  accounted  for.  We  have  seen  that  they 
are  used  by  the  Lucanus  elai^lius  of  North  America  for 
seizing  the  female.  As  they  are  so  conspicuous  and  so 
elegantly  branched,  and  as  owing  to  their  great  length 
they  are  not  well  adapted  for  pinching,  the  suspicion  has 
crossed  my  mind  that  they  may  in  addition  serve  as  an 
ornament,  like  the  horns  on  the  head  and  thorax  of  the 
various  species  above  described.  The  male  Chiasognathus 
Granfii  of  S.  Chili — a  splendid  beetle  belonging  to  the 
same  family — has  enormously  developed  mandibles  (fig.  24); 
he  is  bold  and  pugnacious;  when  threatened  he  faces  round, 
opens  his  great  jaws,  and  at  the  same  time  stridulates 
loudly.  But  the  mandibles  were  not  strong  enough  to  pinch 
my  finger  so  as  to  cause  actual  pain. 

*  Quoted  from  Fischer,  in  "Diet.  Class.  d'Hist.  Nat.,"  torn.  x.  p. 
324. 

f  "  Ann,  Soc.  Entomolog.  France,"  1866,  as  quoted  in  "Journal  of 
Travel,"  by  A,  Murray,  1868,  p.  135. 


INSECTS. 


341 


Sexual  selection,  which  implies  the  possession  of  con- 
siderable perceptive  powers  and  of  strong  passions,  seems  to 
have  been  more  effective  with  the 
Lamellicorns  than  with  any  other 
family  of  beetles.  With  some  species 
the  males  are  provided  with  weapons 
for  fighting;  some  live  in  pairs  and 
show  mutual  affection;  many  have 
the  power  of  stridulating  when  ex- 
cited; many  are  furnished  with  the 
most  extraordinary  horns,  apparently 
for  the  sake  of  ornament;  and  some, 
which  are  diurnal  in  their  habits,  are 
gorgeously  colored.  Lastly,  several 
of  the  largest  beetles  in  the  world 
belong  to  this  family,  which  was 
placed  by  Linnaeus  and  Fabricius  at 
the  head  of  the  order.* 


Strhlvlatmg  Organs. — Beetles  be- 
longing to  many  and  widely  distinct 
families  possess  these  organs.  The 
sound  thus  produced  can  sometimes 
be  heard  at  the  distance  of  several 
feet  or  even  yards,  f  but  it  is  not 
comparable  with  that  made  by  the 
Orthoptera.  The  rasp  generally  con- 
sists of  a  narrow,  sUghtly  raised  sur- 
face, crossed  by  very  fine,  parallel 
ribs,  sometimes  so  fine  as  to  cause 
iridescent  colore,  and  having  a  very 
elegant  appearance  under  the  micro- 
scope. In  some  cases,  as  with  Ty- 
phceus,  minute,  bristly  or  scale-like 
prominences,  with  which  the  whole 
surrounding  surface  is  covered  in 
approximately  parallel  lines,  could 
be  traced  passing  into  the  ribs  of  the  Fig.  ai.  chiasopmathus  oran- 
i-asp.      The    transition   takes  place     mkil^lowe'ifijurerfemaie: 


*  Westwood,  "  Modern  Class.,"  vol.  i,  p.  184. 
f  WoUaston,   "On  Certain  Musical  Curculionidae,' 
Mag.  of  Nat.  Hist.,"  vol.  vi,  1860,  p.  14. 


Annals    and 


342 


THE  DESCENT  OF  MAN. 


by  their  becoming  confluent  and  straight,  and  at  the 
same  time  mere  prominent  and  smooth.  A  hard  ridge 
on  an  adjoining  part  of  the  body  serves  as  the  scraper 
for  the  rasp,  but  this  scraper  in  some  cases  has  been  spe- 
cially modified  for  the  purpose.  It  is  rapidly  moved  across 
the  rasp,  or  conversely  the  rasp  across  the  scraper. 


Fig.  25. 


Necrophorus  (from  Landois).    r.    The  two  rasps.    Left-hand 
figure,  part  of  the  rasp  highly  magnified. 


These  organs  are  situated  in  widely  different  positions. 
In  the  carrion -beetles  (Necrophorus)  two  parallel  rasps 
(r,  fig.  25)  stand  on  the  dorsal  surface  of  the  fifth  abdomi- 
nal segment,  each  rasp*  consisting  of  126  to  140  fine  ribs. 
These  ribs  are  scraped  against  the  posterior  margins  of  the 
elytra,  a  small  portion  of  which  projects  beyond  the  gen- 
eral outline.  In  many  Crioceridse,  and  in  Clythra  4:-punc- 
tata  (one  of  the  Chrysomelidae),  and  in  some  Tenebrionidse, 
etc.,t  the  rasp  is  seated  on  the  dorsal  apex  of  the  abdomen, 
on  the  pygidium  or  pro-pygidium,  and  is  scraped  in  the 
same  manner  by  the  elytra.  In  Heterocerus,  which  belongs 
to  another  family,  the  rasps  are  placed  on  the  sides  of  the 
first  abdominal  segment  and  are  scraped  by  ridges  on  the 

*  Landois,  "  Zeitschrift  fiir  wiss.  Zoolog.,"  B.  xvii,  1867,  s.  127. 

f  I  am  greatly  indebted  to  Mr.  G.  R.  Crotch  for  having  sent  me 
many  prepared  specimens  of  various  beetles  belonging  to  these  three 
families  and  to  others,  as  well  as  for  valuable  information.  He  be- 
lieves that  the  power  of  stridulation  in  tlie  Clythra  has  not  been  pre- 
viously observed.  I  am  also  much  indebted  to  Mr.  E.  W.  Janson, 
for  information  and  specimens,  1  may  add  that  my  son  Mr.  F. 
Darwin,  finds  that  Dermestes  murimus  stridulates,  but  he  searched 
in  vain  for  the  apparatus.  Scolytus  has  lately  been  described  by  Dr. 
Chapman  as  a  stridulator,  in  the  "  Entomologist's  Monthly  Maga- 
zine," vol.  vi,  p.  130. 


WSEGT^. 


^3 


femora.*  In  certain  Ciirculionidse  and  Carabidaef  the 
parts  are  completely  reversed  in  position,  for  the  rasps  are 
seated  on  the  interior  surface  of  the  elytra,  near  their 
apices,  or  along  their  outer  margins,  and  the  edges  of  the 
abdominal  segments  serves  as  the  scrapers.  In  Pelohius 
Hermanni  (one  of  Dytiscidae  or  water-beetles)  a  strong 
ridge  runs  parallel  and  near  to  the  sutural  margin  of  the 
elytra  and  is  crossed  by  ribs,  coarse  in  the  middle  part,  but 
becoming  gradually  finer  at  both  ends,  especially  at  the 
upper  end:  when  this  insect  is  held  under  water  or  in  the 
air  a  stridulating  noise  is  produced  by  the 
extreme  horny  margin  of  the  abdomen  being 
scraped  against  the  rasps.  In  a  great  num- 
ber of  long-horned  beetles  (Longicornia)  the 
organs  are  situated  quite  otherwise,  the  rasp 
being  on  the  meso-thorax,  which  is  rubbed 
against  the  pro-thorax.  Landois  counted  238 
very  fine  ribs  on  the  rasp  of  Cerambyx  heros. 
Many  Lamellicorns  have  the  power  of 
stridulating,  and  the  organs  differ  greatly  in 
position.  Some  species  stridulate  very 
loudly,  so  that  when  Mr.  F.  Smith  caught  a 
Trox  sahuloHus,  a  gamekeeper  who  stood  by 
thought  he  had  caught  a  mouse;  but  I 
failed  to  discover  the  proper  organs  in  this 
beetle.  In  Geotrupes  and  Typhceus  a  narrow 
ridge  runs  obliquely  across  (r,  fig.  26)  the  coxa 
of  each  hind  leg  (having  in  G.  stercorarius  84 
ribs),  which  is  scraped  by  a  specially  project- 
ing part  of  one  of  the  abdominal  segments. 
In  the  nearly  allied  Copris  lunaris  an  excessively  narrow 
fine  rasp  runs  along  the  sutural  margin  of  the  elytra  with 
another  short  rasp  near  the  basal  outer  margin;  but  in 
some    other    Coprini    the    rasp    is    seated,   according  to 

*  Schiodte,  translated  in  "  Annals  and  Mag.  of  Nat.  Hist.,"  vol.  xx, 
1867,  p.  37. 

f  Westring  has  described  (Kroyer,  "  Naturhist.  Tidskrift,"  B.  ii, 
1848-1849,  p.  334)  the  stridulating  organs  in  these  two,  as  well  as  in 
other  families.  In  the  Carabida?  I  have  examined  Elaphnis  idigi- 
noms  and  Blethisa  multipunctata,  sent  to  me  bv  Mr.  Crotch.  In 
Blethisa  the  transverse  ridges  on  the  furrowed  border  of  the  abdom- 
inal segment  do  not,  as  far  as  I  could  judge,  come  into  play  in  scrap- 
ing the  rasps  on  the  elytra. 


Fiff.  26.    Hind  leg 
of    Geotrupes 
stercorarius. 
From  Landois 

r.  Easp.    c.  Coxa. 

/.  Femur,  t.  Tibia. 

tr.  Tarsi. 


344  THE  DESCENT  OF  MAN. 

Leconte,*  on  the  dorsal  surface  of  the  abdomen.  In 
Oryctes  it  is  seated  on  the  propygidium;  and;,  according 
to  the  same  entomologist,  in  some  other  Dynastini  on  the 
under  surface  of  the  elytra.  Lastly,  Westring  states  that 
in  OmalopUa  hrunnea  the  rasp  is  placed  on  the  pro-sternum 
and  the  scraper  on  the  meta-sternum,  the  parts  thus  occu- 
pying the  under  surface  of  the  body  instead  of  the  upper 
surface,  as  in  the  Longicorns. 

We  thus  see  that  in  the  different  coleopterous  families 
the  stridulating  organs  are  wonderfully  diversified  in 
position,  but  not  much  in  structure.  Within  the  same 
family  some  species  are  provided  with  these  organs,  and 
others  are  destitute  of  them.  This  diversity  is  intelligible, 
if  we  suppose  that  originally  various  beetles  made  a  shuf- 
fling or  hissing  noise  by  the  rubbing  together  of  any  hard 
and  rough  parts  of  their  bodies,  which  happened  to  be  in 
contact;  and  that  from  the  noise  thus  produced  being  in 
some  way  useful,  the  rough  surfaces  were  gradually  devel- 
oped into  regular  stridulating  organs.  Some  beetles  as  they 
move  now  produce,  either  intentionally  or  unintentionally, 
a  shuffling  noise  without  possessing  any  proper  organs  for 
the  purpose.  Mr.  Wallace  informs  me  that  the  Eiicliirus 
longimanus  (a  Lamellicorn,  with  the  anterior  legs  wonder- 
fully elongated  in  the  male)  ^'  makes,  while  moving,  a  low 
hissing  sound  by  the  protrusion  and  contraction  of  the 
abdomen ;  and  when  seized-  it  produces  a  grating  sound 
by  rubbing  its  hind  legs  against  the  edges  of  the  elytra." 
The  hissing  sound  is  clearly  due  to  a  narrow  rasp  running 
along  the  sutural  margin  of  each  elytron;  and  I  could  like- 
wise make  the  grating  sound  by  rubbing  the  shagreened  sur- 
face of  the  femur  against  the  granulated  margin  of  the  cor- 
responding elytron;  but  I  could  not  here  detect  any  proper 
rasp;  nor  is  it  likely  that  I  could  have  overlooked  it  in  so 
large  an  insect.  After  examining  Cychrus,  and  reading 
what  Westring  has  written  about  this  beetle,  it  seems  very 
doubtful  whether  it  possesses  any  true  rasp,  though  it  has 
the  power  of  emitting  a  sound. 

From  the  analogy  of  the  Orthoptera  and  Homoptera,  I 
expected  to  find  the  stridulating  organs  in  the  Colpeotera 
differing  according  to  sex;  but  Landois,  who  has  carefully 

*  I  am  indebted  to  Mr.  Walsli,  of  Illinois,  for  Laving  sent  me  ex- 
tracts from  Leconte's  "  Introduction  to  Entomology,"  pp.  101,  143. 


mSEGTS,  345 

examined  several  species,  observed  no  sucli  difference;  nor 
did  Westring;  nor  did  Mr.  G-.  R.  Crotch  in  preparing  the 
many  specimens  which  he  had  the  kindness  to  send  me. 
Any  difference  in  these  organs,  if  slight,  would,  however, 
be  difficult  to  detect,  on  account  of  their  great  variability. 
Thus,  in  the  first  pair  of  specimens  of  Necropliorus 
liumator  and  of  Pelohius  which  I  examined,  the  rasp 
was  considerably  larger  in  the  male  than  in  the  female; 
but  not  so  with  succeeding  specimens.  In  Geotrupes 
stercorarius  the  rasp  appeared  to  me  thicker,  opaquer 
and  more  prominent  in  three  males  than  in  the  same 
number  of  females ;  in  order,  therefore,  to  discover 
whether  the  sexes  differed  in  their  power  of  stridulat- 
ing,  my  son,  Mr.  F.  Darwin,  collected  fifty-seven  living 
specimens,  which  he  separated  into  two  lots,  according  as 
they  made  a  greater  or  lesser  noise,  when  held  in  the  same 
manner.  He  then  examined  all  these  specimens  and  found 
that  the  males  were  very  nearly  in  the  same  proportion 
to  the  females  in  both  the  lots.  Mr.  F.  Smith  has  kept 
alive  numerous  specimens  of  Monoynclms  pseudacori  (Cur- 
culionidae),  and  is  convinced  that  both  sexes  stridulate, 
and  apparently  in  an  equal  degree. 

Nevertheless,  the  power  of  stridulating  is  certainly  a 
sexual  character  in  some  few  Coleoptera.  Mr.  Crotch  dis- 
covered that  the  males  alone  of  two  species  of  Heliopathes 
(Tenebrionidae)  possess  stridulating  organs.  I  examined 
five  males  of  ^.  gibbus,  and  in  all  these  there  was  a  well- 
developed  rasp,  partially  divided  into  two,  on  the  dorsal 
surface  of  the  terminal  abdominal  segment;  while  in  the 
same  number  of  females  there  was  not  even  a  rudiment  of 
the  rasp,  the  membrane  of  this  segment  being  transparent 
and  much  thinner  than  in  the  male.  In  H.  cribratostriatus 
the  male  has  a  similar  rasp,  excepting  that  it  is  not  par- 
tially divided  into  two  portions,  and  the  female  is  com- 
pletely destitute  of  this  organ;  the  male  in  addition  has  on 
the  apical  margins  of  the  elytra,  on  each  side  of  the  suture, 
three  or  four  short  longitudinal  ridges,  which  are  crossed 
by  extremely  fine  ribs,  parallel  to  and  resembling  those  on 
the  abdominal  rasp;  whether  these  ridges  serve  as  an  inde- 
pendent rasp  or  as  a  scraper  for  the  abdominal  rasp,  I  could 
not  decide ;  the  female  exhibits  no  trace  of  this  latter 
structure. 

Again,  in  three  species  of  the  Lamellicorn  genus  Oryc- 


346  TBE  DESCENT  OF  MAN. 

tes,  we  have  a  nearly  parallel  case.  In  the  females  of  0. 
grypMts  and  nasicornis  the  ribs  on  the  rasp  of  the  pro- 
pygidium  are  less  continuous  and  less  distinct  than  in  the 
males;  but  the  chief  difference  is  that  the  whole  upper  sur- 
face of  this  segment,  when  held  in  the  proper  light,  is  seen 
to  be  clothed  with  hairs,  which  are  absent  or  are  repre- 
sented by  excessively  fine  down  in  the  males.  It  should  be 
noticed  that  in  all  Coleoptera  the  effective  part  of  the  rasp 
is  destitute  of  hairs.  In  0.  senegalensis  the  difference  be- 
tween the  sexes  is  more  strongly  marked,  and  this  is  best 
seen  when  the  proper  abdominal  segment  is  cleaned  and 
viewed  as  a  transparent  object.  In  the  female  the  whole 
surface  is  covered  with  little  separate  crests  bearing  spines; 
while  in  the  male  these  crests,  in  proceeding  toward  the 
apex,  become  more  and  more  confluent,  regular  and  naked; 
so  that  three-fourths  of  the  segment  is  covered  with  ex- 
tremely fine  parallel  ribs,  which  are  quite  absent  in  the 
female.  In  the  females,  however,  of  all  three  species  of 
Oryctes,  a  slight  grating  or  stridulating  sound  is  produced 
when  the  abdomen  of  a  softened  specimen  is  pushed  back- 
ward and  forward. 

In  the  case  of  the  Heliopathes  and  Oryctes  there  can 
hardly  be  a  doubt  that  the  males  stridulate  in  order  to  call 
or  to  excite  the  females;  but  with  most  beetles  the  stridu- 
lation  apparently  serves  both  sexes  as  a  mutual  call. 
Beetles  stridulate  under  various  emotions,  in  the  same 
manner  as  birds  use  their  voices  for  many  purposes  besides 
singing  to  their  mates.  The  great  Chiasognathus  stridu- 
lates  in  anger  or  defiance;  many  species  do  the  same  from 
distress  or  fear,  if  held  so  that  they  cannot  escape ;  by 
striking  the  hollow  stems  of  trees  in  the  Canary  Islands, 
Messrs.  Wollaston  and  Crotch  were  able  to  discover  the 
presence  of  beetles  belonging  to  the  genus  Acalles  by  their 
stridulation.  Lastly,  the  male  Ateuchus  stridulates  to  en- 
courage the  female  in  her  work,  and  from  distress  when  she 
is  removed.*  Some  naturalists  believe  that  beetles  make 
this  noise  to  frighten  away  their  enemies;  but  I  cannot 
think  that  a  quadruped  or  bird,  able  to  devour  a  large 
beetle,  would  be  frightened  by  so  slight  a  sound.  The 
belief  that  the  stridulation  serves  as  a  sexual  call  is  sup- 

*M.  P.  de  la  Brulerie,  as  quoted  in  *•  Journal  of  Travel,"  A.  Mur- 
ray, vol.  i.  1868,  p   135. 


ported  by  the  fact  that  death-ticks  {AnoMum  tessellatum) 
are  well  known  to  answer  each  other^s  ticking,  and,  as  I 
have  myself  observed,  a  tapping  noise  artificially  made. 
Mr.  Doiibleday  also  informs  me  that  he  has  sometimes  ob- 
served a  female  ticking,*  and  in  an  hour  or  two  afterward 
has  found  her  united  with  a  male,  and  on  one  occasion  sur- 
rounded by  several  males.  Finally,  it  is  probable  that  the 
two  sexes  of  many  kinds  of  beetles  were  at  first  enabled  to 
find  each  other  by  the  slight  shuffling  noise  produced  by 
the  rubbing  together  of  the  adjoining  hard  parts  of  their 
bodies;  and  that  as  those  males  or  females  which  made  the 
greatest  noise  succeeded  best  in  finding  partners,  rugosities 
on  various  parts  of  their  bodies  were  gradually  developed 
by  means  of  sexual  selection  into  true  stridulating  organs. 

*  According  to  Mr.  Doubleday,  "tlie  noise  is  produced  by  the 
insect  raising  itself  on  its  legs  as  liigli  as  it  can,  and  then  striking  its 
thorax  five  or  six  times  in  rapid  succession  against  the  substance 
upon  which  it  is  sitting."  For  references  on  this  subject  see  Landois, 
" Zeitschrift  fiir  wissen.  Zoolog.,"  B,  xvii,  s.  131.  Olivier  says  (as 
quoted  by  Kirby  and  Spence,  "  Introduct.,"  vol.  ii,  p.  395)  that  the 
female  of  Pinielia  stnata  produces  a  rather  loud  sound  by  striking 
her  abdomen  against  any  hard  substance,  "  and  that  the  male,  obedi- 
ent to  this  call,  soon  attends  her,  and  they  pair." 


348  THE  DESCENT  OF  MAN, 


CHAPTER  XI. 

INSECTS,  continued. — order  lepidoptera. 

(butterflies  and  moths.) 

Courtship  of  butterflies — Battles — Ticking  noise — Colors  common  to 
both  sexes,  or  more  brilliant  in  the  males — Examples — Not  due 
to  the  direct  action  of  the  conditions  of  life — Colors  adapted  for 
protection — Colors  of  moths — Display — Perceptive  powers  of  the 
Lepidoptera  —  Variability  —  Causes  of  the  difference  in  color 
between  the  males  and  females — Mimicry,  female  butterflies  more 
brilliantly  colored  than  the  males — Bright  colors  of  caterpillars — 
Summary  and  concluding  remarks  on  the  secondary  sexual  char- 
acters of  insects — Birds  and  insects  compared. 

1^  this  great  order  the  most  interesting  points  for  us  are 
the  differences  in  color  between  the  sexes  of  the  same 
species,  and  between  the  distinct  species  of  the  same  genus. 
Nearly  the  whole  of  the  following  chapter  will  be  devoted 
to  this  subject;  but  I  will  first  make  a  few  remarks  on  one 
or  two  other  points.  Several  males  may  often  be  seen  pur- 
suing and  crowding  round  the  same  female.  Their  court- 
ship appears  to  be  a  prolonged  affair,  for  I  have  frequently 
watched  one  or  more  males  pirouetting  round  a  female 
until  I  was  tired,  without  seeing  the  end  of  the  courtship. 
Mr.  A.  G.  Butler  also  informs  me  that  he  has  several  times 
watched  a  male  courting  a  female  for  a  full  quarter  of  an 
hour;  but  she  pertinaciously  refused  him,  and  at  last  set-, 
tied  on  the  ground  and  closed  her  wings,  so  as  to  escape 
from  his  addresses. 

Although  butterflies  are  weak  and  fragile  creatures,  they 
are  pugnacious,  and  an  Emperor  butterfly*  has  been  capt- 
ured with  the  tips  of  its  wings  broken  from  a  conflict  with 
another  male.  Mr.  Collingwood,  in  speaking  of  the  fre- 
quent battles  between  the  butterflies  of  Borneo,  says:  '^  They 

*  Apatura  Iris:  "  The  Entomologist's  Weekly  Intelligence,"  1859, 
p.  139.  For  the  Bornean  Butterflies,  see  C.  Collingwood,  "  Rambles 
of  a  Naturalist,"  1868,  p.  183. 


INSECTS.  349 

whirl  round  each  other  with  the  greatest  rapidity,  and 
appear  to  be  incited  by  the  greatest  ferocity/' 

The  Ageronia  feronia  makes  a  noise  like  that  produced 
by  a  toothed  wheel  passing  under  a  spring  catch,  and 
which  can  be  heard  at  the  distance  of  several  yards;  I 
noticed  this  sound  at  Rio  de  Janeiro,  only  when  two  of 
these  butterflies  were  chasing  each  other  in  an  irregular 
course,  so  that  it  is  probably  made  during  the  courtship  of 
the  sexes.* 

Some  moths  also  produce  sounds;  for  instance,  the  males 
of  Thecophora  fovea.  On  two  occasions  Mr.  F.  Buchanan 
White  t  heard  a  sharp  quick  noise  made  by  the  male  of 
Hylophila  prasinanUy  and  which  he  believes  to  be  produced, 
as  in  Cicada,  by  an  elastic  membrane,  furnished  with  a 
muscle.  He  quotes,  also,  Guenee,  that  Setina  produces  a 
sound  like  the  ticking  of  a  watch,  apparently  by  the  aid  of 
'^  two  large  tympaniform  vesicles,  situated  in  the  pectoral 
region;"  and  these  "  are  much  more  developed  in  the  male 
than  in  the  female."  Hence  the  sound-producing  organs  in 
the  Lepidoptera  appear  to  stand  in  some  relation  with  the 
sexual  functions.  I  have  not  alluded  to  the  well-known 
noise  made  by  the  Death's  Head  Sphinx,  for  it  is  generally 
heard  soon  after  the  moth  has  emerged  from  its  cocoon. 

Giard  has  always  observed  that  the  musky  odor,  which 
is  emitted  by  two  species  of  Sphinx  moths,  is  peculiar  to 
the  males;  J  and  in  the  higher  classes  we  shall  meet  with 
many  instances  of  the  males  alone  being  odoriferous. 

Every  one  must  have  admired  the  extreme  beauty  of 
many  butterflies  and  of  some  moths;  and  it  may  be  asked, 
are  their  colors  and  diversified  patterns  the  result  of  the 
direct  action  of  the  physical  conditions  to  which  these 
insects  have  been  exposed,  without  any  benefit  being  thus 
derived?  Or  have  successive  variations  been  accumulated 
and  determined  as  a  protection,  or  for  some  unknown  pur- 
pose, or  that  one  sex  may  be  attractive  to  the  other?  And, 

*  See  my  "Journal  of  Researches,"  1845,  p.  33.  Mr.  Doubleday 
has  detected  ("Proc.  Ent.  Soc.,"  March  3,  1845,  p.  123)  a  peculiar 
membranous  sac  at  the  base  of  the  front  win^,  which  is  probably 
connected  with  the  production  of  the  sound.  For  the  case  of  Theco- 
phora, see  "Zoological  Record,"  1869,  p.  401.  For  Mr.  Buchanan 
White's  observations,  "  The  Scottish  Naturalist,"  July,  1872,  p.  214. 

t  "The  Scottish  Naturalist,"  July,  1872,  p.  213, 

t  "  Zoological  Becord,"  1869,  p.  '347.     • 


350  THE  DESCENT  OF  MAN. 

again,  what  is  the  meaning  of  the  colors  being  widely  dif- 
ferent in  the  males  and  females  of  certain  species,  and 
alike  in  the  two  sexes  of  other  species  of  the  same  genus? 
Before  attempting  to  answer  these  questions  a  body  of 
facts  must  be  given. 

With  our  beautiful  English  butterflies,  the  admiral,  pea- 
cock, and  painted  lady  (Vanessae),  as  well  as  many  others, 
the  sexes  are  alike.  This  is  also  the  case  with  the  magnifi- 
cent Heliconidae,  and  most  of  the  Danaidse  in  the  tropics. 
But  in  certain  other  tropical  groups,  and  in  some  of  our 
English  butterflies,  as  the  purple  emperor,  orange-tip,  etc. 
{Apatura  Iris  and  Anthocharis  car  clam  ines),  the  sexes 
differ  either  greatly  or  slightly  in  color.  No  language  suf- 
fices to  describe  the  splendor  of  the  males  of  some  tropical 
species.  Even  within  the  same  genus  we  often  find  species 
presenting  extraordinary  ditt'erences  between  the  sexes, 
while  others  have  their  sexes  closely  alike.  Thus  in  the 
South  American  genus  Epicalia,  Mr.  Bates,  to  whom  I  am 
indebted  for  most  of  the  following  facts,  and  for  looking 
over  this  whole  discussion,  mforms  me  that  he  knows  twelve 
species,  the  two  sexes  of  which  haunt  the  same  stations 
(and  this  is  not  always  the  case  with  butterflies),  and 
which,  therefore,  cannot  have  been  differently  affected  by 
external  conditions.*  In  nine  of  these  twelve  species  the 
males  rank  among  the  most  brilliant  of  all  butterflies,  and 
differ  so  greatly  from  the  comparatively  plain  females  that 
they  were  formerly  placed  in  distinct  genera.  The  females 
of  these  nine  species  resemble  each  other  in  their  general 
type  of  coloration;  and  they  likewise  resemble  both  sexes 
of  the  species  in  several  allied  genera  found  in  various  parts 
of  the  world.  Hence  we  may  infer  that  these  nine  species, 
and  probably  all  the  others  of  the  genus,  are  descended 
from  an  ancestral  form  which  was  colored  in  nearly  the 
same  manner.  In  the  tenth  species  the  female  still  retains 
the  same  general  coloring,  but  the  male  resembles  her,  so 
that  he  is  colored  in  a  much  less  gaudy  and  contrasted 
manner  than  the  males  of  the  previous  species.  In  the 
eleventh  and  twelfth  species  the  females  depart  from  the 
usual  type,  for  they  are  gayly  decorated  almost   like  the 

*  See  also  Mr.  Bates'  paper  in  "  Proc.  Ent.  Soc.  of  Philadelphia," 
1865,  p.  206.  Also  Mr,  Wallace  on  the  same  subject,  in  regard  to 
Diadema,  in   'Transact.  Entomolog.  Soc.  of  London,"  1869,  p.  278 


INSECTS.  351 

males,  but  in  a  somewhat  less  degree.  Hence  in  these  two 
latter  species  the  bright  colors  of  the  males  seem  to  have 
been  transferred  to  the  females;  while  in  the  tenth  species 
the  male  has  either  retained  or  recovered  the  plain  colors  of 
the  female,  as  well  as  of  the  parent-form  of  the  genus.  The 
sexes  in  these  three  cases  have  thus  been  rendered  nearly 
alike,  though  in  an  opposite  manner.  In  the  allied  genus 
Eubagis,  both  sexes  of  some  of  the  species  are  plain-colored 
and  nearly  alike;  while  the  greater  number  of  the  males  are 
decorated  with  beautiful  metallic  tints  in  a  diversified 
manner,  and  differ  much  from  their  females.  The  females 
throughout  the  genus  retain  the  same  general  style  of 
coloring,  so  that  they  resemble  one  another  much  more 
closely  than  they  resemble  their  own  males. 

In  the  genus  Papilio  all  the  species  of  the  ^Eneas  group 
are  remarkable  for  their  conspicuous  and  strongly  con- 
trasted colors,  and  they  illustrate  the  frequent  tendency  to 
gradation  in  the  amount  of  difference  between  the  sexes. 
In  a  few  species,  for  instance  in  P.  ascanius,  the  males  and 
females  are  alike;  in  others  the  males  are  either  a  little 
brighter,  or  very  much  more  superb  than  the  females.  The 
genus  Junonia,  allied  to  our  Vanessa?,  offers  a  nearly 
parallel  case,  for  although  the  sexes  of  most  of  the  species 
resemble  each  other,  and  are  destitute  of  rich  colors,  yet  in 
certain  species,  as  in  J.  cenone,  the  male  is  rather  more 
bright  -  colored  than  the  female,  and  in  a  few  (for 
instance  /.  andremiaja)  the  male  is  so  different  from  the 
female  that  he  might  be  mistaken  for  an  entirely  distinct 
species. 

Another  striking  case  was  pointed  out  to  me  in  the  Brit- 
ish Museum  by  Mr.  A.  Butler,  namely,  one  of  the  tropical 
American  Theclae,  in  which  both  sexes  are  nearly  alike  and 
wonderfully  splendid;  in  another  species  the  male  is  colored 
in  a  similarly  gorgeous  manner,  while  the  whole  upper 
surface  of  the  female  is  of  a  dull  uniform  brown.  Our 
common  little  English  blue  butterflies  of  the  genus  Lycaena 
illustrate  the  various  differences  in  color  between  the  sexes 
almost  as  well,  though  not  in  so  striking  a  manner,  as  the 
above  exotic  genera.  In  Lyccena  agestis  both  sexes  have 
wings  of  a  brown  color,  bordered  with  small  ocellated 
orange  spots  and  are  thus  alike.  In  L.  ORgon  the  wings  of 
the  male  are  of  a  fine  blue  bordered  with  black,  while 
those  of  the  female  are  brown  with  a  similar  border  closely 


352  THE  DESCENT  OF  MAN. 

resembling  the  wings  of  L.  agestis.  Lastly,  in  Z.  arion 
both  sexes  are  of  a  blue  color  and  are  very  like,  though  in 
the  female  the  edges  of  the  wings  are  rather  duskier  with 
the  black  spots  plainer;  and  in  a  bright-blue  Indian  species 
both  sexes  are  still  more  alike. 

I  have  given  the  foregoing  details  in  order  to  show,  in 
the  first  place,  that  when  the  sexes  of  butterflies  differ  the 
male  as  a  general  rule  is  the  more  beautiful  and  departs 
more  from  the  usual  type  of  coloring  of  the  group  to  which 
the  species  belongs.  Hence  in  most  groups  the  females  of 
the  several  species  resemble  each  other  much  more  closely 
than  do  the  males.  In  some  cases,  however,  to  which  I 
shall  hereafter  allude,  the  females  are  colored  more  splen- 
didly than  the  males.  In  the  second  place,  these  details 
have  been  given  to  bring  clearly  before  the  mind  that 
within  the  same  genus  the  two  sexes  frequently  present 
every  gradation  from  no  difference  in  color  to  so  great  a 
difference  that  it  was  long  before  the  two  were  placed  by 
entomologists  in  the  same  genus.  In  the  third  place,  we 
have  seen  that  when  the  sexes  nearly  resemble  each  other 
this  appears  due  either  to  the  male  having  transferred  his 
colors  to  the  female,  or  to  the  male  having  retained  or  per- 
haps recovered  the  primordial  colors  of  the  group.  It  also 
deserves  notice  that  in  those  groups  in  which  the  sexes 
differ  the  females  usually  somewhat  resemble  the  males, 
so  that  when  the  males  are  beautiful  to  an  extraordinary 
degree  the  females  almost  invariably  exhibit  some  degree 
of  beauty.  From  the  many  cases  of  gradation  in  the 
amount  of  difference  between  the  sexes,  and  from  the  prev- 
alence of  the  same  general  type  of  coloration  throughout 
the  whole  of  the  same  group,  we  may  conclude  that  the 
causes  have  generally  been  the  same  which  have  determined 
the  brilliant  coloring  of  the  males  alone  of  some  species, 
and  of  both  sexes  of  other  species. 

As  so  many  gorgeous  butterflies  inhabit  the  tropics  it 
has  often  been  supposed  that  they  owe  their  colors  to  the 
great  heat  and  moisture  of  these  zones;  but  Mr.  Bates*  has 
shown  by  the  comparison  of  various  closely-allied  groups  of 
insects  from  the  temperate  and  tropical  regions  that  this 
view  cannot  be  maintained;  and  the  evidence  becomes  con- 
clusive when  brilliantly  colored   males  and  plain  colored 

*  "The  Naturalist  on  the  Amazons,"  vol.  i,  1863,  p.  19, 


INSECTS.  353 

females  of  the  same  species  inhabit  the  same  district,  feed 
on  t;he  same  food  and  follow  exactly  the  same  habits  of 
life.  Even  when  the  sexes  resemble  each  other  we  can 
hardly  believe  that  their  brilliant  and  beautifully  arranged 
colors  are  the  purposeless  result  of  the  nature  of  the  tissues 
and  of  the  action  of  the  surrounding  conditions. 

With  animals  of  all  kinds,  whenever  color  has  been 
modified  for  some  special  purpose,  this  has  been,  as  far  as 
'we  can  judge,  either  for  direct  or  indirect  protection,  or  as 
an  attraction  between  the  sexes.  With  many  species  of 
butterflies  the  upper  surfaces  of  the  wings  are  obscure;  and 
this  in  all  probability  leads  to  their  escaping  observation 
and  danger.  But  butterflies  would  be  particularly  liable 
to  be  attacked  by  their  enemies  when  at  rest;  and  most 
kinds  while  resting  raise  their  wings  vertically  over  their 
backs,  so  that  the  lower  surface  alone  is  exposed  to  view. 
Hence  it  is  this  side  which  is  often  colored  so  as  to  imitate 
the  objects  on  which  these  insects  commonly  rest.  Dr. 
Rossler,  I  believe,  first  noticed  the  similarity  of  the  closed 
wings  of  certain  Vanessae  and  other  butterflies  to  the  bark 
of  trees.  Many  analogous  and  striking  facts  could  be  given. 
The  most  interesting  one  is  that  recorded  by  Mr.  Wallace* 
of  a  common  Indian  and  Sumatran  butterfly  (Kallima), 
which  disappeai-s  like  magic  when  it  settles  on  a  bush;  for 
it  hides  its  head  and  antennae  between  its  closed  wings, 
which,  in  form,  color  and  veining,  cannot  be  distinguished 
from  a  withered  leaf  with  its  footstalk.  In  some  other 
cases  the  lower  surfaces  of  the  wings  are  brilliantly  colored, 
and  yet  are  protective;  thus  in  Thecla  rubi  the  wings  when 
closed  are  of  an  emerald  green  and  resemble  the  young 
leaves  of  the  bramble,  on  which  in  spring  this  butterfly 
may  often  be  seen  seated.  It  is  also  remarkable  that  in  very 
many  species  in  which  the  sexes  differ  greatly  in  color  on 
their  upper  surface,  the  lower  surface  is  closely  similar  or 
identical  in  both  sexes,  and  serves  as  a  protection,  f 

Although  the  obscure  tints  both  of  the  upper  and  under 
sides  of  many  butterflies  no  doubt  serve  to  conceal  them,  yet 
we  cannot  extend  this  view  to  the  brilliant  and  conspicuous 
colors  on  the  upper  surface  of  such  species  as  our  admiral  and 

*  See  the  interesting  article  in  the  "  Westminster  Review,"  July, 
1867,  p.  10.  A  wood-cut  of  the  Kallima  is  given  by  Mr.  Wallace  in 
"  Hardwicke's  Science  Gossip,"  Sept.,  1867,  p.  196. 

f  Mr.  G.  Fraser,  in  "Nature,"  April,  1871,  p.  489. 


354  THE  DESCENT  OF  MAN, 

peacock  Vanessse,  our  white  cabbage-butterflies  (Pieris),  or 
the  great  swallow-tail  Papilio  which  haunts  the  open  fens — 
for  these  butterflies  are  thus  rendered  visible  to  every  living 
creature.  In  these  species  both  sexes  are  alike;  but  in  the 
common  brimstone  butterfly  ( Gonepteryx  7'hatnni),  the  male 
is  of  an  intense  yellow,  while  the  female  is  much  paler;  and 
in  the  orange-tip  (Anthocharis  cardamines)  the  males  alone 
have  their  wings  tipped  with  bright  orange.  Both  thS 
males  and  females  in  these  cases  are  conspicuous,  and  it  is 
not  credible  that  their  difference  in  color  should  stand  in 
any  relation  to  ordinary  protection.  Prof.  Weismann 
remarks  *  that  the  female  of  one  of  the  Lycaenae  expands 
her  brown  wings  when  she  settles  on  the  ground,  and  is 
then  almost  invisible;  the  male,  on  the  other  hand,  as  if 
aware  of  the  danger  incurred  from  the  bright  blue  of  the 
upper  surface  of  his  wings,  rests  with  the  inclosed;  and  this 
shows  that  the  blue  color  cannot  be  in  any  way  protective. 
Nevertheless,  it  is  probable  that  conspicuous  colors  are 
indirectly  beneficial  to  many  species,  as  a  warning  that  they 
are  unpalatable.  For  in  certain  other  cases,  beauty  has 
been  gained  through  the  imitation  of  other  beautiful 
species,  which  inhabit  the  same  district  and  enjoy  an  im- 
munity from  attack  by  being  in  some  way  offensive  to  their 
enemies;  but  then  we  have  to  account  for  the  beauty  of  the 
imitated  species. 

As  Mr.  Walsh  has  remarked  to  me,  the  females  of  our 
orange-tip  butterfly,  above  referred  to,  and  of  an  American 
species  (Anth.  genutia)  probably  show  us  the  primordial 
colors  of  the  parent-species  of  the  genus;  for  both  sexes  of 
four  or  five  widely-distributed  species  are  colored  in  nearly 
the  same  manner.  As  in  several  previous  cases,  we  may 
here  infer  that  it  is  the  males  of  Anth.  cardamines  and 
genutia  which  have  departed  from  the  usual  type  of  the 
genus.  In  the  Anth.  sara  from  California,  the  orange  tips 
to  the  wings  have  been  partially  developed  in  the  female  ; 
but  they  are  paler  than  in  the  male,  and  slightly  different 
in  some  other  respects.  In  an  allied  Indian  form,  the 
Iphias  glaucippe,  the  orange-tips  are  fully  developed  in 
both  sexes.  In  this  Iphias,  as  pointed  out  to  me  by  Mr.  A. 
Butler,  the  under  surface  of  the  wings  marvelously  resem- 
bles a  pale-colored  leaf;  and  in  our  English  orange-tip,  the 

*  '  JEinfluss  dey  Igolirun^  auf  di.  Artbildung,"  1872,  p.  58, 


INSECTS.  355 

under  surface  resembles  the  flower-head  of  the  wild  parsley, 
on  which  the  butterfly  often  rests  at  night.*  The  same 
reason  which  compels  us  to  believe  that  the  lower  surfaces 
have  here  been  colored  for  the  sake  of  protection,  leads  us 
to  deny  that  the  wings  have  been  tipped  with  bright  orange 
for  the  same  purpose,  especiall}'  when  this  character  is  con- 
fined to  the  males. 

Most  moths  rest  motionless  during  the  whole  or  greater 
part  of  the  day  with  their  wings  depressed;  and  the  whole 
upper  surface  is  often  shaded  and  colored  in  an  admirable 
manner,  as  Mr.  Wallace  has  remarked,  for  escaping  detec- 
tion. The  front- wings  of  the  BombycidaB  and  Noctuid8e,f 
when  at  rest,  generally  overlap  and  conceal  the  hind  wings; 
so  that  the  latter  might  be  brightly  colored  without  much 
risk;  and  they  are  in  fact  often  thus  colored.  During 
flight,  moths  would  often  be  able  to  escape  from  their  ene- 
mies; nevertheless,  as  the  hind  wings  are  then  fully  exposed 
to  view,  their  bright  colors  must  generally  have  been 
acquired  at  some  little  risk.  But  the  following  fact  shows 
how  cautious  w^e  ought  to  be  in  drawing  conclusions  on  this 
head.  The  common  yellow  under  wings  (Triphaena)  often 
fly  about  during  the  day  or  early  evening,  and  are  then 
conspicuous  from  the  color  of  their  hind  wings.  It  would 
naturally  be  thought  that  this  would  be  a  source  of  danger; 
but  Mr.  J.  Jenner  AVeir  believes  that  it  actually  serves 
them  as  a  means  of  escape,  for  birds  strike  at  these  brightly 
colored  and  fragile  surfaces,  instead  of  at  the  body.  For 
instance,  Mr.  Weir  turned  into  his  aviary  a  vigorous  speci- 
men of  Triphcena  pronuba,  which  was  instantly  pursued  by 
a  robin :  but  the  bird^s  attention  being  caught  by  the  col- 
ored wings,  the  moth  was  not  captured  until  after  about 
fifty  attempts,  and  small  portions  of  the  wings  were  repeat- 
edly broken  off.  He  tried  the  same  experiment  in  the 
open  air,  with  a  swallow  and  T.  fimbria ;  but  the  large 
size  of  this  moth  probably  interfered  with  its  capture.  J; 
We  are  thus  reminded  of  a  statement  made  by  Mr.  Wal- 

*  See  the  interesting  observations  by  Mr.  T.  W.  Wood,  "  The 
Student,"  Sept.,  1868,  p.  81. 

f  Mr.  Wallace  in  "  Hardwicke's  Science  Gossip,"  Sept.,  1867,  p.  193. 

X  See  also  on  this  subject,  Mr.  Weir's  paper  in  "  Transjict.  Ejit, 
Soc.,"1869,  p.  23,  ^ 


356  THE  DESCENT  OF  MAN. 

lace,*  namel}^  that  in  the  Brazilian  forests  and  Malayan 
islands,  many  common  and  highly-decorated  butterflies 
are  weak  flyers,  though  furnished  with  a  broad  expanse  of 
wing;  and  they  ^'are  often  captured  with  pierced  and 
broken  wings,  as  if  they  had  been  seized  by  birds,  from 
which  they  had  escaped;. if  the  wings  had  been  much 
smaller  in  proportion  to  the  body,  it  seems  probable  that 
the  insect  would  more  frequently  have  been  struck  or 
pierced  in  a  vital  part,  and  thus  the  increased  expanse  of 
the  wings  may  have  been  indirectly  beneficial." 

Display. — The  bright  colors  of  many  butterflies  and  of 
some  moths  are  specially  arranged  for  display,  so  that  they 
may  be  readily  seen.  During  the  night  colors  are  not  vis- 
ible, and  there  can  be  no  doubt  that  the  nocturnal  moths, 
taken  as  a  body,  are  much  less  gayly  decorated  than  butter- 
flies, all  of  which  are  diurnal  in  their  habits.  But  the 
moths  of  certain  families,  such  as  the  Zyggenid^e,  several 
Sphingidae,  Uraniidse,  some  Arctiidae  and  Saturniidae,  fly 
about  during  the  day  or  early  evening,  and  many  of  these 
are  extremely  beautiful,  being  far  brighter-colored  than  the 
strictly  nocturnal  kinds.  A  few  exceptional  cases,  how- 
ever, of  bright  -  colored  nocturnal  species  have  been 
recorded,  f 

There  is  evidence  of  another  kind  in  regard  to  display. 
Butterflies,  as  before  remarked,  elevate  their  wings  when 
at  rest,  but  while  basking  in  the  sunshine  often  alternately 
raise  and  depress  them,  thus  exposing  both  surfaces  to  full 
view;  and  although  the  lower  surface  is  often  colored  in  an 
obscure  maimer  as  a  protection,  yet  in  many  species  it  is  as 
highly  decorated  as  the  upper  surface,  and  sometimes  in  a 
very  different  manner.  In  some  tropical  species  the  lower 
surface  is  even  more  brilliantly  colored  than  the  upper.  J; 
In  the  English  fritillaries  {Argynnis)  the  lower  surface 

*"  Westminster  Review,"  July,  1867,  p.  16. 

f  For  instance,  Lithosia;  but  Prof.  Westwood  ("Modern  Class,  of 
Insects,"  vol.  ii,  p.  890)  seems  surprised  at  this  case.  On  the  relative 
colors  of  diurnal  and  nocturnal  Lepidoptera,  see  ibid.,  pp.  333,  392; 
also  Harris,  "  Treatise  on  the  Insects  of  New  England,"  1842,  p.  315. 

\  Such  differences  between  the  upper  and  lower  surfaces  of  the 
wings  of  several  species  of  Papiliomay  be  seen  in  the  beautiful  plates 
to  Mr.  Wallace's  "Memoir  on  the  Papilionidse  of  the  Malayan 
Region,"  in  "Transact.  Linn.  Soc,"  vol.  xxv,  part  i,  1865. 


INSECTS.  357 

alone  is  ornamented  with  shining  silver.  Nevertheless,  as 
a  general  rule,  the  upper  surface,  which  is  probably  more 
fully  exposed,  is  colored  more  brightly  and  diversely  than 
the  lower.  Hence  the  lower  surface  generally  affords  to 
entomologists  the  more  useful  character  for  detecting  the 
affinities  of  the  various  species.  Fritz  Miiller  informs  me 
that  three  species  of  Castnia  are  found  near  his  house  in 
S.  Brazil;  of  two  of  them  the  hind  wings  are  obscure,  and 
are  always  covered  by  the  front  wings  when  these  butter- 
flies are  at  rest;  but  the  third  species  has  black  hind  wings, 
beautifully  spotted  with  red  and  white,  and  these  are  fully 
expanded  and  displayed  whenever  the  butterfly  rests.  Other 
such  cases  could  be  added. 

If  we  now  turn  to  the  enormous  group  of  moths  which, 
as  I  hear  from  Mr.  Stainton,  do  not  habitually  expose  the 
under  surface  of  their  wings  to  full  view,  we  find  this  side 
very  rarely  colored  with  a  brightness  greater  than,  or  even 
equal  to,  that  of  the  upper  side.  Some  exceptions  to  the 
rule,  either  real  or  apparent,  must  be  noticed,  as  the  case  of 
Hypopyra.*  Mr.  Trimen  informs  me  that  in  Guenee's 
great  work  three  moths  are  figured,  in  which  the  under  sur- 
face is  much  the  more  brilliant.  For  instance,  in  the  Aus- 
tralian Gastrophora  the  upper  surface  of  the  fore  wing  is 
pale  grayish-ochreous,  while  the  lower  surface  is  magnifi- 
cently ornamented  by  an  ocellus  of  cobalt-blue,  placed  in 
the  midst  of  a  black  mark,  surrounded  by  orange-yellow, 
and  this  by  bluish-white.  But  the  habits  of  these  three 
moths  are  unknown;  so  that  no  explanation  can  be  given 
of  their  unusual  style  of  coloring.  Mr.  Trimen  also 
informs  me  that  the  lower  surface  of  the  wings  in  certain 
other  Geometrae  f  and  quadrifid  Noctuae  are  either  more 
variegated  or  more  brightly-colored  than  the  upper  surface; 
but  some  of  these  species  have  the  habit  of  "  holding  their 
wings  quite  erect  over  their  backs,  retaining  them  in  this 
position  for  a  considerable  time,"  and  thus  exposing  the 
under  surface  to  view.  Other  species,  when  settled  on  the 
ground  or  herbage,  now  and  then  suddenly  and  slightly  lift 

*See  Mr.  Wormald  on  this  motli ;  "  Proc.  Ent.  Soc.,"  March  2, 
1868. 

f  See  also  an  account  of  the  South  American  genus  Erateina  (one 
of  the  Geometrae)  in  "Transact.  Ent.  Soc,"  new  series,  vol.  v,  pis 
X.V  and  xvi. 


358  ^'^^  DESCENT  OF  MAN. 

up  their  wings.  Hence  the  lower  surface  of  the  wings 
being  brighter  than  the  upper  surface  in  certain  moths  is 
not  so  anomalous  as  it  at  first  appears.  The  Saturniidae 
include  some  of  the  most  beautiful  of  all  moths,  their  wings 
bein^  decorated,  as  in  our  British  Emperor  moth,  with  fine 
ocelli;  and  Mr.  T.  W.  Wood*  observes  that  they  resemble 
butterflies  in  some  of  their  movements;  ^^for  instance,  in 
the  gentle  waving  up  and  down  of  the  wings  as  if  for  dis- 
play, which  is  more  characteristic  of  diurnal  than  of 
nocturnal  Lepidoptera.^^ 

It  is  a  singlar  fact  that  no  British  moths  which  are 
brilliantly  colored,  and,  as  far  as  I  can  discover,  hardly  any 
foreign  species,  differ  much  in  color  according  to  sex; 
though  this  is  the  case  with  many  brilliant  butterflies.  The 
male,  however,  of  one  American  moth,  the  Saturnia  lo,  is 
described  as  having  its  fore  wings  deep  yellow,  curiously 
marked  with  purplish-red  spots;  while  the  wings  of  the 
female  are  purple-brown,  marked  with  gray  lines,  f  The 
British  moths  which  differ  sexually  in  color  are  all  brown, 
or  of  various  dull  yellow  tints,  or  nearly  white.  In  several 
species  the  males  are  much  darker  than  the  females,];  and 
these  belong  to  groups  which  generally  fly  about  during 
the  afternoon.  On  the  other  hand,  in  many  genera,  as 
Mr.  Stainton  informs  me,  the  males  have  the  hind  wings 
whiter  than  those  of  the  female — of  which  fact  Agrotis 
exclamationis  offers  a  good  instance.  In  the  Giiost  Moth 
{Hepialus  humuli)  the  difference  is  more  strongly 
marked;   the   males   being  white  and   the  females  yellow 

*"Proc.  Ent.  Soc.  of  London,"  July  6,  1868,  p.  27. 

f  Harris,  "Treatise,"  etc.,  edited  by  Flint,  1862,  p   395. 

\  For  instance,  I  observe  in  my  son's  cabinet  that  the  males  are 
darker  than  the  females  in  the  Ladocampa  quercus,  Odonestis  pota- 
toria,  Hypogymna  dispar,  Dasychira  pudibunda  and  Cycnia  mendica. 
In  this  latter  species  the  difference  in  color  between  the  two  sexes  is 
strongly  marked;  and  Mr.  Wallace  informs  me  that  we  here  have,  as 
he  believes,  an  instance  of  protective  mimicry  confined  to  one  sex,  as 
will  hereafter  be  more  fully  explained.  The  white  female  of  the 
Cycnia  resembles  the  very  common  Spilosoma  menthrasti,  both  sexes 
of  which  are  white;  and  Mr.  Stainton  observed  that  this  latter  moth 
was  rejected  with  utter  disgust  by  a  whole  brood  of  young  turkeys, 
which  were  fond  of  eating  other  moths;  so  that  if  the  Cycnia  was 
commonly  mistaken  by  British  birds  for  the  Spilosoma,  it  would  es- 
cape being  devoured,  and  its  white,  deceptive  color  would  thus  be 
highly  beneficial. 


with  darker  markings.*  It  is  probable  that  in  these 
cases  the  males  are  thus  rendered  more  conspicuous,  and 
more  easily  seen  by  the  females  while  flying  about  in  the 
dusk. 

From  the  several  foregoing  facts  it  is  impossible  to  admit 
that  the  brilliant  colors  of  butterflies,,  and  of  some  few 
moths,  have  commonly  been  acquired  for  the  sake  of  pro- 
tection. We  have  seen  that  their  colors  and  elegant  pat- 
terns are  arranged  and  exhibited  as  if  for  display.  Hence 
I  am  led  to  believe  that  the  females  prefer  or  are  most 
excited  by  the  more  brilliant  males;  for  on  any  other  sup- 
position the  males  would,  as  far  as  we  can  see,  be  orna- 
mented to  no  purpose.  We  know  that  ants  and  certain 
Lamellicorn  beetles  are  capable  of  feeling  an  attachment 
for  each  other,  and  that  ants  recognize  their  fellows  after 
an  interval  of  several  months.  Hence  there  is  no  abstract 
improbability  in  the  Lepidoptera,  which  probably  stand 
nearly  or  quite  as  high  in  the  scale  as  these  insects,  having 
sufficient  mental  capacity  to  admire  bright  colors.  They 
certainly  discover  flowers  by  color.  The  humming-bird 
sphinx  may  often  be  seen  to  swoop  down  from  a  distance 
on  a  bunch  of  flowers  in  the  midst  of  green  foliage;  and  I 
have  been  assured  by  two  persons  abroad  that  these  moths 
repeatedly  visit  flowers  painted  on  the  walls  of  a  room  and 
vainly  endeavor  to  insert  their  proboscis  into  them.  Fritz 
Miiller  informs  me  that  several  kinds  of  butterflies  in 
S.  Brazil  show  an  unmistakable  preference  for  certain 
colors  over  others.  He  observed  that  they  very  often 
visited  the  brilliant  red  flowers  of  flve  or  six  genera  of 
plants,  but  never  the  white  or  yellow  flowering  species  of 
the  same  and  other  genera  growing  in  the  same  garden; 
and  I  have  received  other  accounts  to  the  same  effect.  As 
I  hear  from  Mr.  Doubleday,  the  common  white  butterfly 
often  flies  down  to  a  bit  of  paper  on  the  ground,  no  doubt 
mistaking  it  for  one  of  its  own  species.     Mr.  Oollingwoodf 

*  It  is  remarkable  tliat  in  tlie  Shetland  Islands  the  male  of  this 
moth,  instead  of  differing  widely  from  the  female,  frequently  resem- 
bles her  closely  in  color  (see  Mr.  MacLachlan,  "  Transact.  Ent.  Soc," 
vol.  ii,  1866,  p.  459).  Mr.  G,  Fraser  suggests  ("Nature,"  April, 
1871,  p.  489)  that  at  the  season  of  the  year  when  the  ghost-moth  ap- 
pears in  these  northern  islands,  the  whiteness  of  the  males  would 
not  be  needed  to  render  them  visible  to  the  females  in  the  twilight 
night. 

I  "  Rambles  of  a  Naturalist  in  the  Chinese  Seas,"  1868,  p.  183. 


360  TBE  DESCENT  OF  MAN. 

in  speaking  of  the  difficulty  in  collecting  certain  butter- 
flies in  the  Malay  Archipelago,  states  that  "  a  dead  speci- 
men pinned  upon  a  conspicuous  twig  will  often  arrest  an 
insect  of  the  same  species  in  its  headlong  flight  and  bring 
it  down  within  easy  reach  of  the  net,  especially  if  it  be  of 
the  opposite  sex." 

The  courtship  of  butterflies  is,  as  before  remarked,  a 
prolonged  aftair.  The  males  sometimes  fight  together  in 
rivalry;  and  many  may  be  seen  pursuing  or  crowding  round 
the  same  female.  Unless,  then,  the  females  prefer  one 
male  to  another  the  pairing  must  be  left  to  mere  chance, 
and  this  does  not  appear  probable.  If,  on  the  other  hand, 
the  females  habitually,  or  even  occasionally,  prefer  the 
more  beautiful  males,  the  colors  of  the  latter  will  have  been 
rendered  brighter  by  degrees,  and  will  have  been  trans- 
mitted to  both  sexes  or  to  one  sex,  according  to  the  law  of 
inheritance  which  has  prevailed.  The  process  of  sexual 
selection  will  have  been  much  facilitated,  if  the  conclusion 
can  be  trusted,  arrived  at  from  various  kinds  of  evidence 
in  the  supplement  to  the  ninth  chapter;  namely,  that  the 
males  of  many  Lepidoptera,  at  least  in  the  imago  state, 
greatly  exceed  the  females  in  number. 

Some  facts,  however,  are  opposed  to  the  belief  that  female 
butterflies  prefer  the  more  beautiful  males;  thus,  as  I  have 
been  assured  by  several  collectors,  fresh  females  may  fre- 
quently be  seen  paired  with  battered,  faded,  or  dingy  males; 
but  this  is  a  circumstance  which  could  hardly  fail  often  to 
follow  from  the  males  emerging  from  their  cocoons  earlier 
than  the  females.  With  moths  of  the  family  of  the  Bom- 
bycidse,  the  sexes  pair  immediately  after  assuming  the 
imago  state;  for  they  cannot  feed,  owing  to  the  rudiment- 
ary condition  of  their  mouths.  The  females,  as  several 
entomologists  have  remarked  to  me,  lie  in  an  almost  torpid 
state,  and  appear  not  to  evince  the  least  choice  in  regard  to 
their  partners.  This  is  the  case  with  the  common  silk-moth 
{B.  mori),  as  I  have  been  told  by  some  continental  and 
English  breeders.  Dr.  Wallace,  who  has  had  great  experi- 
ence in  breeding  Bomhyx  cynthia,  is  convinced  that  the 
females  evince  no  choice  or  preference.  He  has  kept  above 
three  hundred  of  these  moths  together,  and  has  often  found 
the  most  vigorous  females  mated  with  stunted  males.  The 
reverse  appears  to  occur  seldom;  for,  as  he  believes,  the 
more  vigorous  males  pass  over  the  weakly  females^  and  are 


INSECTS,  361 

attracted  by  those  endowed  with  most  vitality.  Never- 
theless, the  Bombycidae,  though  obscurely  colored,  are 
often  beautiful  to  our  eyes  from  their  elegant  and  mottled 
shades. 

I  have  as  yet  only  referred  to  the  species  in  which  the 
males  are  brighter  colored  than  the  females,  and  I  have 
attributed  their  beauty  to  the  females  for  many  generations 
having  chosen  and  paired  with  the  more  attractive  males. 
But  converse  cases  occur,  though  rarely,  in  which  the 
females  are  more  brilliant  than  the  males;  and  here,  as  I 
believe,  the  males  have  selected  the  more  beautiful  females, 
and  have  thus  slowly  added  to  their  beauty.  We  do  not 
know  why  in  various  classes  of  animals  the  males  of  some 
few  species  have  selected  the  more  beautiful  females  instead 
of  having  gladly  accepted  any  female,  as  seems  to  be  the 
general  rule  in  the  animal  kingdom;  but  if,  contrary  to 
what  generally  occurs  with  the  Lepidoptera,  the  females 
were  much  more  numerous  than  the  males,  the  latter  would 
be  likely  to  pick  out  the  more  beautiful  females.  Mr.  But- 
ler showed  me  several  species  of  Callidryas  in  the  British 
Museum,  in  some  of  which  the  females  equaled,  and  in 
others  greatly  surpassed,  the  males  in  beauty ;  for  the 
females  alone  have  the  borders  of  their  wings  suffused  with 
crimson  and  orange  and  spotted  with  black.  The  plainer 
males  of  these  species  closely  resemble  each  other,  showing 
that  here  the  females  have  been  modified;  whereas  in  those 
cases,  where  the  males  are  the  more  ornate,  it  is  these  which 
have  been  modified,  the  females  remaining  closely  alike. 

In  England  we  have  some  analogous  cases,  though  not  so 
marked.  The  females  alone  of  two  species  of  Thecla  have 
a  bright  purple  or  orange  patch  on  their  fore  wings.  In 
Hipparchia  the  sexes  do  not  differ  much  ;  but  it  is  the 
female  of  H.  janira  which  has  a  conspicuous  light  brown 
patch  on  her  wings;  and  the  females  of  some  of  the  other 
species  are  brighter  colored  than  their  males.  Again, 
the  females  of  Colias  edusa  and  liyale  have  '^^  orange  or 
yellow  spots  on  the  black  marginal  border,  represented  in 
the  males  only  by  thin  streaks;^'  and  in  Pieris  it  is  the 
females  which  *^are  ornamented  with  black  spots  on  the 
fore  wings,  and  these  are  only  partially  present  in  the 
males."  Now  the  males  of  many  butterflies  are  known  to 
support  the  females  during  their  marriage  flight;  but  in 
the  species  just  named  it  is  the  females  which  support  the 


362  TIIJS  DESCENT  OF  MAN. 

males;  so  that  the  part  which  the  two  sexes  play  is  reversed, 
as  is  their  relative  beauty.  Throughout  the  animal  king- 
dom the  males  commonly  take  the  more  active  share  in 
wooing,  and  their  beauty  seems  to  have  been  increased  by 
the  females  having  accepted  the  more  attractive  individuals; 
but  with  these  butterflies  the  females  take  the  more  active 
part  in  the  final  marriage  ceremony,  so  that  we  may  sup- 
pose that  they  likewise  do  so  in  the  wooing;  and  in  this  case 
we  can  understand  how  it  is  that  they  have  been  rendered 
the  more  beautiful.  Mr.  Meldola,  from  whom  the  fore- 
going statements  have  been  taken,  says  in  conclusion: 
^'  Though  I  am  not  convinced  of  the  action  of  sexual  selec- 
tion in  producing  the  colors  of  insects,  it  cannot  be  denied 
that  these  facts  are  strikingly  corroborative  of  Mr.  Darwin's 
views.  * 

As  sexual  selection  primarily  depends  on  variability,  a 
few  words  must  be  added  on  this  subject.  In  respect  to 
color  there  is  no  difficulty,  for  any  number  of  highly  variable 
Lepidoptera  could  be  named.  One  good  instance  will  suffice. 
Mr.  Bates  showed  me  a  whole  series  of  specimens  of  Papilio 
sesostris  and  P.  childrenm;  in  the  latter  the  males  varied 
much  in  the  extent  of  the  beautifully  enameled  green  patch 
on  the  fore  wings,  and  in  the  size  of  the  white  mark,  and 
of  the  splendid  crimson  stripe  on  the  hind  wings;  so  that 
there  was  a  ^reat  contrast  among  the  males  between  the 
most  and  the  least  gaudy.  The  male  of  Papilio  sesostris 
is  much  less  beautiful  than  of  P.  childrencB;  and  it  like- 
wise varies  a  little  in  the  size  of  the  green  patch  on  the 
fore  wings,  and  in  the  occasional  appearance  of  the  small 
crimson  stripe  on  the  hind  wings,  borrowed,  as  it  would 
seem,  from  its  own  female;  for  the  females  of  this  and  of 
many  other  species  in  the  iEneas  group  possess  this  crimson 
stripe.  Hence  between  the  brightest  specimens  of  P.  ses- 
ostris and  the  dullest  of  P.  childrenm  there  was  but  a  small 
interval;  and  it  was  evident  that  as  far  as  mere  variability 
is  concerned,  there  would  be  no  difficulty  in  permanently 
increasing  the  beauty  of  either  species  by  means  of  selec- 
tion.    The  variability  is  here  almost  confined  to  the  male 

*  "Nature,"  April  27,  1871,  p.  508.  Mr.  Meldola  quotes  Donzel, 
in  "Soc.  Ent.  de  France,"  1837,  p.  77,  on  the  flight  of  butterflies 
while  pairing.  See  also  Mr.  G.  Fraser,  in  "  Nature,"  April  20,  1871, 
p.  489,  on  the  sexual  differences  of  several  British  butterflies. 


INSECTS.  363 

sex;  but  Mr.  Wallace  and  Mr.  Bates  have  shown  *  that  the 
females  of  some  species  are  extremely  variable,  the  males 
being  nearly  constant.  In  a  future  chapter  I  shall  have 
occasion  to  show  that  the  beautiful  eye-like  spots,  or  ocelli, 
found  on  the  wings  of  many  Lepidoptera  are  eminently 
variable.  I  may  here  add  that  these  ocelli  offer  a  difficulty 
on  the  theory  of  sexual  selection;  for  though  appearing  to 
us  so  ornamental,  they  are  never  present  in  one  sex  and 
absent  in  the  other,  nor  do  they  ever  differ  much  in  the 
two  sexes,  t  This  fact  is  at  present  inexplicable;  but  if  it 
should  hereafter  be  found  that  the  formation  of  an  ocellus 
is  due  to  some  change  in  the  tissues  of  the  wings,  for 
instance,  occurring  at  a  very  early  period  of  development, 
we  might  expect,  from  what  we  know  of  the  laws  of  inherit- 
ance, that  it  would  be  transmitted  to  both  sexes,  though 
arising  and  perfected  in  one  sex  alone. 

On  the  whole,  although  many  serious  objections  may  be 
urged,  it  seems  probable  that  most  of  the  brilliantly-colored 
species  of  Lepidoptera  owe  their  colors  to  sexual  selection, 
excepting  in  certain  cases,  presently  to  be  mentioned,  in 
which  conspicuous  colors  have  been  gained  through  mimicry 
as  a  protection.  From  the  ardor  of  the  male  throughout 
the  animal  kingdom  he  is  generally  willing  to  accept  any 
female;  and  it  is  the  female  which  usually  exerts  a  choice. 
Hence,  if  sexual  selection  has  been  efficient  with  the 
Lepidoptera,  the  male,  when  the  sexes  differ,  ought  to  be 
the  more  brilliantly  colored,  and  this  undoubtedly  is  the 
case.  When  both  sexes  are  brilliantly  colored  and  resemble 
each  other  the  characters  a<;quired  by  the  males  appear  to 
have  been  transmitted  to  both.  We  are  led  to  this  conclu- 
sion by  cases,  even  within  the  same  genus,  of  gradation 
from  an  extraordinary  amount  of  difference  to  identity  in 
color  between  the  two  sexes. 

But  it  may  be  asked  whether  the  differences  in  color 
between  the  sexes  may  not  be  accounted  for  by  other  means 

♦Wallace  on  the  Papilionidae  of  the  Malayan  Region,  in  "Trans- 
act. Linn.  Soc.,"  vol.  xxv,  1865,  pp.  8,  36.  A  striking  case  of  a  rare 
variety,  strictly  intermediate  between  two  other  well-marked  female 
varieties,  is  given  by  Mr.  Wallace.  See  also  Mr.  Bates,  in  "  Proc. 
Entomolog.  Soc.,"  Nov.  19,  1866,  p.  40. 

f  Mr.  Bates  was  so  kind  as  to  lay  this  subject  before  the  Entomo- 
logical Society,  and  I  have  received  answers  to  this  effect  from  several 
entomologists. 


364  THE  DESCENT  OF  MAN. 

besides  sexual  selection.  Thus  the  males  and  females  of  the 
same  species  of  butterfly  are  in  several  cases  known  *  to 
inhabit  different  stations,  the  former  commonly  basking  in 
the  sunshine,  the  latter  liaunting  gloomy  forests.  It  is 
therefore  possible  that  different  conditions  of  life  may  have 
acted  directly  on  the  two  sexes;  but  this  is  not  probable, f  as 
in  the  adult  state  they  are  exposed  to  different  conditions 
during  a  very  short  period ;  and  the  larvae  of  both  are 
exposed  to  the  same  conditions.  Mr.  Wallace  believes  that 
the  difference  between  the  sexes  is  due  not  so  much  to  the 
males  having  been  modified,  as  to  the  females  having  in  all 
or  almost  all  cases  acquired  dull  colors  for  the  sake 
of  protection.  It  seems  to  me,  on  the  contrary,  far 
more  probable  that  it  is  the  males  which  have  been 
chiefly  modified  through  sexual  selection,  the  females  having 
been  comparatively  little  changed.  We  can  thus  under- 
stand how  it  is  that  the  females  of  allied  species  generally 
resemble  one  another  so  much  more  closely  than  do  the 
males.  They  thus  show  us  approximately  the  primordial 
coloring  of  the  parent-species  of  the  group  to  which  they 
belong.  They  have,  however,  almost  always  been  somewhat 
modified  by  the  transfer  to  them  of  some  of  the  successive 
variations,  through  the  accumulation  of  which  the  males 
were  rendered  beautiful.  But  I  do  not  wish  to  deny  that 
the  females  alone  of  some  species  may  have  been  specially 
modified  for  protection.  In  most  cases  the  males  and 
females  of  distinct  species  will  have  been  exposed  during 
their  prolonged  larval  state  to  different  conditions,  and 
may  have  been  thus  affected  ;  though  with  the  males  any 
slight  change  of  color  thus  caused  will  generally  have  been 
masked  by  the  brilliant  tints  gained  through  sexual  selec- 
tion. When  we  treat  of  birds,  I  shall  have  to  discuss  the 
whole  question,  as  to  how  far  the  dift'erences  in  color 
between  the  sexes  are  due  to  the  males  having  been  modi- 
fied through  sexual  selection  for  ornamental  purposes,  or 
to  the  females  having  been  modified  through  natural  selec- 
tion for  the  sake  of  protection,  so  that  I  will  here  say  but 
little  on  the  subject. 

In  all  the  cases  in  which  the  more  common  form  of  equal 

*H.  W.  Bates,  "The  Naturalist  on  the  Amazons,"  vol.  ii,  1863,  p. 
228.     A.  R.  Wallace,  in  "  Transact.  Linn.  Soc,"  vol.  xxv,  1865,  p.  10. 

f  On  this  whole  subject  see  "The  Variation  of  Animals  and  Plants 
under  Domestication,"  1868,  vol.  ii,  chap,  xxiii. 


INSECTS.  365 

inheritance  by  both  sexes  has  prevailed,  the  selection  of 
bright-colored  males  would  tend  to  make  the  females 
bright  colored ;  and  the  selection  of  dull-colored  females 
would  tend  to  make  the  males  dull.  If  both  processes 
were  carried  on  simultaneously,  they  would  tend  to  coun- 
teract each  other ;  and  the  final  result  would  depend  on 
whether  a  greater  number  of  females  from  being  well  pro- 
tected by  obscure  colors,  or  a  greater  number  of  males  by 
being  brightly  colored  and  thus  finding  partners,  succeeded 
in  leaving  more  numerous  offspring. 

In  order  to  account  for  the  frequent  transmission  of  char- 
acters to  one  sex  alone,  Mr.  Wallace  expresses  his  belief  that 
the  more  common  form  of  equal  inheritance  by  both  sexes 
can  be  changed  through  natural  selection  into  inheritance 
by  one  sex  alone,  but  in  favor  of  this  view  I  can  discover 
no  evidence.  We  know  from  what  occurs  under  domestica- 
tion that  new  characters  often  appear,  which  from  the  first 
are  transmitted  to  one  sex  alone  ;  and  by  the  selection  of 
such  variations  there  would  not  be  the  slightest  difficulty 
in  giving  bright  colors  to  the  males  alone,  and  at  the  same 
time  or  subsequently,  dull  colors  to  the  females  alone.  In 
this  manner  the  females  of  some  butterflies  and  moths 
have,  it  is  probable,  been  rendered  inconspicuous  for  the 
sake  of  protection,  and  widely  different  from  their  males. 

I  am,  however,  unwilling  without  distinct  evidence  to 
admit  that  two  complex  processes  of  selection,  each  requir- 
ing the  transference  of  new  characters  to  one  sex  alone, 
have  been  carried  on  with  a  multitude  of  species — that  the 
males  have  been  rendered  more  brilliant  by  beating  their 
rivals,  and  the  females  more  dull  colored  by  having  escaped 
from  their  enemies.  The  male,  for  instance,  of  the  common 
brimstone  butterfly  (Gonepteryx),  is  of  a  far  more  intense 
yellow  than  the  female,  though  she  is  equally  conspicuous; 
and  it  does  not  seem  probable  that  she  specially  acquired 
her  pale  tints  as  a  protection,  though  it  is  probable  that 
the  male  acquired  his  bright  colors  as  a  sexual  attraction. 
The  female  of  Aiithocharis  cardamines  does  not  possess 
the  beautiful  orange  wing-tips  of  the  male  ;  consequently 
she  closely  resembles  the  white  butterflies  (Pieris)  so  com- 
mon in  our  gardens;  but  we  have  no  evidence  that  this 
resemblance  is  beneficial  to  her.  As,  on  the  other  hand,  she 
resembles  both  sexes  of  several  other  species  of  the  genus 
inhabiting  various  quarters  of  the  world,  it  is  probable  that 


366  THE  DESCENT  OF  MAN, 

she  has  simply  retained  to  a  large  extent  her  primordial 
colors. 

Finally,  as  we  have  seen,  various  considerations  lead  to  the 
conclusion  that  with  the  greater  number  of  brilliantly  col- 
ored Lepidoptera  it  is  the  male  which  has  been  chiefly 
modified  through  sexual  selection;  the  amount  of  difference 
between  the  sexes  mostly  depending  on  the  form  of  inherit- 
ance which  has  prevailed.  Inheritance  is  governed  by  so 
many  unknown  laws  or  conditions  that  it  seems  to  us  to  act 
in  a  capricious  manner;*  and  we  can  thus,  to  a  certain  ex- 
tent, understand  how  it  is  that  with  closely  allied  species 
the  sexes  either  differ  to  an  astonishing  degree,  or  are  iden- 
tical in  color.  As  all  the  successive  steps  in  the  process  of 
variation  are  necessarily  transmitted  through.the  female,  a 
greater  or  less  number  of  such  steps  might  readily  become 
developed  in  her;  and  thus  we  can  understand  the  frequent 
gradations  from  an  extreme  difference  to  none  at  all  between 
the  sexes  of  allied  species.  These  cases  of  gradation,  it 
may  be  added,  are  much  too  common  to  favor  the  supposi- 
tion that  we  here  see  females  actually  undergoing  the 
process  of  transition  and  losing  their  brightness  for  the 
sake  of  protection;  for  we  have  every  reason  to  conclude 
that  at  any  one  time  the  greater  number  of  species  are  in  a 
fixed  condition. 

Mimicry. — This  principle  was  first  made  clear  in  an  ad- 
mirable paper  by  Mr.  Bates,  f  who  thus  threw  a  flood  of 
light  on  many  obscure  problems.  It  had  previously  been 
observed  that  certain  butterflies  in  South  America  belong- 
ing to  quite  distinct  families  resembled  the  Heliconidae  so 
closely  in  every  stripe  and  shade  of  color  that  they  could 
not  be  distinguished  save  by  an  experienced  entomologist. 
As  the  Heliconidae  are  colored  in  their  usual  manner,  while 
the  others  depart  from  the  usual  coloring  of  the  groups  to 
which  they  belong,  it  is  clear  that  the  latter  are  the  imi- 
tators, and  the  Heliconidae  the  imitated.  Mr.  Bates  further 
observed  that  the  imitating  species  are  comparatively  rare, 
while  the  imitated  abound,  and  that  the  two  sets  live  min- 
gled together.     From  the  fact  of  the  Heliconidae  being 

*  "  The  Variation  of  Animals  and  Plants  under  Domestication,"  vol. 
ii,  chap,  xii,  p.  17. 
f  "Transact.  Linn.  Soc,"  vol.  xxiii,  1862,  p.  495. 


INSECTS.  367 

conspicuous  and  beautiful  insects,  yet  so  numerous  in  indi- 
viduals and  species,  he  concluded  that  they  must  be  pro- 
tected from  the  attacks  of  enemies  by  some  secretion  or 
odor;  and  this  conclusion  has  now  been  amply  confirmed,* 
especially  by  Mr.  Belt.  Hence  Mr.  Bates  inferred  that  the 
butterflies  which  imitate  the  protected  species  have  acquired 
their  present  marvelously  deceptive  appearance  through 
variation  and  natural  selection,  in  order  to  be  mistaken  for 
the  protected  kinds,  and  thus  to  escape  being  devoured. 
No  explanation  is  here  attempted  of  the  brilliant  colors  of 
the  imitated,  but  only  of  the  imitating  butterflies.  We 
must  account  for  the  colors  of  the  former  in  the  same  gen- 
eral manner  as  in  the  cases  previously  discussed  in  this 
chapter.  Since  the  publication  of  Mr.  Bates'  paper  similar 
and  equally  striking  facts  have  been  observed  by  Mr.  Wal- 
lace in  the  Malayan  region,  by  Mr.  Trimen  in  S.  Africa, 
and  by  Mr.  Riley  in  the  United  States,  f 

As  some  writers  have  felt  much  difficulty  in  understand- 
ing how  the  first  steps  in  the  process  of  mimicry  could 
have  been  effected  through  natural  selection,  it  may  be  well 
to  remark  that  the  process  probably  commenced  long  ago 
between  forms  not  widely  dissimilar  in  color.  In  this  case 
even  a  slight  variation  would  be  beneficial  if  it  rendered 
the  one  species  more  like  the  other;  and  afterward  the 
imitated  species  might  be  modified  to  an  extreme  degree 
through  sexual  selection  or  other  means,  and  if  the  changes 
were  gradual  the  imitators  might  easily  be  led  along  the 
same  track,  until  they  differed  to  an  equally  extreme  degree 
from  their  original  condition;  and  they  would  thus  ulti- 
mately assume  an  appearance  or  coloring  wholly  unlike 
that  of  the  other  members  of  the  group  to  which  they 
belonged.  It  should  also  be  remembered  that  many  species 
of  Lepidoptera  are  liable  to  considerable  and  abrupt  varia- 
tions in  color.  A  few  instances  have  been  given  in  this 
chapter;  and  many  more  may  be  found  in  the  papers  of 
Mr.  Bates  and  Mr.  Wallace. 

*"Proc.  Ent.  Soc.,"  Dec.  3,  1866,  p.  45. 

f  Wallace,  "Transact.  Linn.  Soc.,"  vol.  xxv,  1865,  p.  1;  also 
"Transact.  Ent.  Soc.,"  vol.  iv  (3d  series),  1867,  p.  301.  Trimen, 
"Linn.  Transact.,"  vol.  xxvi,  1869,  p.  497.  Riley,  "Third  Annual 
Report  on  the  Noxious  Insects  of  Missouri,"  1871,  pp.  163-168.  This 
latter  essay  is  valuable,  as  Mr.  Riley  here  discusses  all  the  objections 
which  have  been  raised  against  Mr.  Bates'  theory. 


368  THE  DESCENT  OF  MAN. 

With  several  species  the  sexes  are  alike,  and  imitate  the 
two  sexes  of  another  species.  But  Mr.  Trimen  gives,  in 
the  paper  already  referred  to,  three  cases  in  which  the  sexes 
of  the  imitated  form  differ  from  each  other  in  color,  and 
the  sexes  of  the  imitating  form  differ  in  a  like  manner. 
Several  cases  have  also  been  recorded  where  the  females 
alone  imitate  brilliantly-colored  and  protected  species,  the 
males  retaining  *^  the  normal  aspect  of  their  immediate  con- 
geners.'^ It  is  here  obvious  that  the  successive  variations 
by  which  the  female  has  been  modified  have  been  trans- 
mitted to  her  alone.  It  is,  however,  probable  that  some  of 
the  many  successive  variations  would  have  been  transmitted 
to,  and  developed  in,  the  males  had  not  such  males  been 
eliminated  by  being  thus  rendered  less  attractive  to  the 
females;  so  that  only  those  variations  were  preserved  which 
were  from  the  first  strictly  limited  in  their  transmission  to 
the  female  sex.  We  have  a  partial  illustration  of  these 
remarks  in  a  statement  by  Mr.  Belt;  *  that  the  males  of 
some  of  the  Leptalides,  which  imitate  protected  species, 
still  retain  in  a  concealed  manner  some  of  their  original 
characters.  Thus  in  the  males  "  the  upper  half  of  the 
lower  wing  is  of  a  pure  white,  while  all  the  rest  of  the  wings 
is  barred  and  spotted  with  black,  red  and  yellow,  like  the 
species  they  mimic.  The  females  have  not  this  white 
patch,  and  the  males  usually  conceal  it  by  covering  it  with 
the  upper  wing,  so  that  I  cannot  imagine  its  being  of  any 
other  use  to  them  than  as  an  attraction  in  courtship,  when 
they  exhibit  it  to  the  females,  and  thus  gratify  their  deep- 
seated  preference  for  the  normal  color  of  the  order  to  which 
the  Leptalides  belong. '^ 

Bright  Colors  of  Caterpillars, — While  reflecting  on  the 
beauty  of  many  butterflies  it  occurred  to  me  that  some 
caterpillars  were  splendidly  colored;  and  as  sexual  selection 
could  not  possibly  have  here  acted,  it  appeared  rash  to 
attribute  the  beauty  of  the  mature  insect  to  this  agency, 
unless  the  bright  colors  of  their  larvae  could  be  somehow 
explained.  In  the  first  place,  it  may  be  observed  that  the 
colors  of  caterpillars  do  not  stand  in  any  close  correlation 
with  those  of  the  mature  insect.  Secondly,  their  bright 
colors  do  not  serve  in  any  ordinary  manner  as  a  protection. 

*  "  The  Naturalist  in  Nicaragua,"  1874,  p.  385. 


INSECTS.  369 

Mr.  Bates  informs  me,  as  an  instance  of  this,  that  the  most 
conspicuous  caterpillar  which  he  ever  beheld  (that  of  a 
Sphinx)  lived  on  the  large  green  leaves  of  a  tree  on  the 
open  llanos  of  South  America;  it  was  about  four  inches  in 
length,  transversely  banded  with  black  and  yellow,  and 
with  its  head,  legs  and  tail  of  a  bright  red.  Hence  it 
caught  the  eye  of  any  one  who  passed  by,  even  at  the 
distance  of  many  yards,  and  no  doubt  that  of  every  passing 
bird. 

I  then  applied  to  Mr.  Wallace,  who  has  an  innate  genius 
for  solving  difficulties.  After  some  consideration  he  replied: 
"  Most  caterpillars  require  protection,  as  may  be  inferred 
from  some  kinds  being  furnished  with  spines  or  irritating 
hairs  and  from  many  being  colored  green  like  the  leaves  on 
which  they  feed,  or  being  curiously  like  the  twigs  of  the  trees 
on  which  they  live.^'  Another  instance  of  protection,  fur- 
nished me  by  Mr.  J.  Mansel  Weale,  may  be  added,  namely, 
that  there  is  a  caterpillar  of  a  moth  which  lives  on  the 
mimosas  in  S.  Africa,  and  fabricates  for  itself  a  case  quite 
indistinguishable  from  the  surrounding  thorns.  From 
such  considerations  Mr.  Wallace  thought  it  probable  that 
conspicuously  colored  caterpillars  were  protected  by  having 
a  nauseous  taste;  but  as  their  skin  is  extremely  tender, 
and  as  their  intestines  readily  protrude  from  a  wound,  a 
slight  peck  from  the  beak  of  a  bird  would  be  as  fatal  to 
them  as  if  they  had  been  devoured.  Hence,  as  Mr.  Wal- 
lace remarks,  "^  distastef ulness  alone  would  be  insufficient 
to  protect  a  caterpillar  unless  some  outward  sign  indicated 
to  its  would-be  destroyer  that  its  prey  was  a  disgusting 
morsel."  Under  these  circumstances  it  would  be  highly 
advantageous  to  a  caterpillar  to  be  instantaneously  and 
certainly  recognized  as  unpalatable  by  all  birds  and  other 
animals.  Thus  the  most  gaudy  colors  would  be  service- 
able, and  might  have  been  gained  by  variation  and  the 
survival  of  the  most  easily  recognized  individuals. 

This  hypothesis  appears  at  first  sight  very  bold,  but 
when  it  was  brought  before  the  Entomological  Society*  it 
was  supported  by  various  statements;  and  Mr.  J.  Jenner 
Weir,  who  keeps  a  large  number  of  birds  in  an  aviary, 
informs   me  that  he  has  made  many  trials  and  finds  no 

*  "  Prop,  Entomolog.  Soc,"  Dec.  3.  1866,  p.  45,  and  March  4, 1867, 
p.  80. 


370  THE  DESCENT  OF  MAN. 

exception  to  the  rule  that  all  caterpillars  of  nocturnal  and 
retiring  habits  with  smooth  skins,  all  of  a  green  color  and 
all  which  imitate  twigs  are  greedily  devoured  by  his  birds. 
The  hairy  and  spinose  kinds  are  invariably  rejected,  as 
were  four  conspicuously  colored  species.  When  the  birds 
rejected  a  caterpiller  the^  plainly  showed  by  shaking  their 
heads  and  cleansing  their  beaks  that  they  were  disgusted 
by  the  taste.*  Three  conspicuous  kinds  of  caterpillars  and 
moths  were  also  given  to  some  lizards  and  frogs  by  Mr.  A. 
Butler  and  were  rejected,  though  other  kinds  were  eagerly 
eaten.  Thus  the  probability  of  Mr.  Wallace's  view  is  con- 
firmed, namely,  that  certain  caterpillars  have  been  made 
conspicuous  for  their  own  good,  so  as  to  be  easily  recog- 
nized by  their  enemies,  on  nearly  the  same  principle  that 
poisons  are  sold  in  colored  bottles  by  druggists  for  the  good 
of  man.  We  cannot,  however,  at  present  thus  explain  the 
elegant  diversity  in  the  colors  of  many  caterpillars;  but 
any  species  which  had  at  some  former  period  acquired  a 
dull,  mottled  or  striped  appearance,  either  in  imitation  of 
surrounding  objects  or  from  the  direct  action  of  climate, 
etc.,  almost  certainly  would  not  become  uniform  in  color 
when  its  tints  were  rendered  intense  and  bright;  for  in 
order  to  make  a  caterpiller  merely  conspicuous  there  would 
be  no  selection  in  any  definite  direction. 

Summary  and  Concluding  Remarks  on  Insects. — Looking 
back  to  the  several  orders  we  see  that  the  sexes  often  diifer 
in  various  charactecs,  the  meaning  of  which  is  not  in  the 
least  understood.  UThe  sexes,  also,  often  differ  in  their 
organs  of  sense  and  means  of  locomotion,  so  that  the  males 
may  quickly  discover  and  reach  the  females.  They  differ 
still  oftener  in  the  males  possessing  diversified  contrivances 
for  retaining  the  females  when  found.  We  are,  however, 
here  concerned  only  in  a  secondary  degree  with  sexual  dif- 
f^ences  of  these  kinds.  _j 

Lin  almost  all  the  orders  the  males  of  some  species,  even 
of  weak  and  delicate  kinds,  are  known  to  be  highly  pug- 

*See  Mr.  J.  Jenner  Weir's  paper  on  Insects  and  Insectivorous 
Birds,  in  "Transact.  Ent.  Soc,"  1869,  p.  21;  also  Mr.  Butler's  paper, 
ibid.,  p.  27.  Mr.  Riley  has  given  analogous  facts  in  the  "Third 
Annual  Report  on  the  Noxious  Insects  of  Missouri,"  1871,  p.  148. 
Some  opposed  cases  are,  however,  given  by  Dr.  Wallace  and  M.  H. 
d'Orville;  see  "  Zoological  Record,"  1869,  p.  349, 


INSECTS.  371 

naoious;  and  some  few  are  furaislied  with  special  weapons 
for  fighting  with  their  rivals.  But  the  law  of  battle  does 
not  prevail  nearly  so  widely  with  insects  as  with  the  higher 
animals.  Hence  it  probably  arises  that  it  is  in  only  a 
few  cases  that  the  males  have  been  rendered  larger  and 
stronger  than  the  females.  On  the  contrary,  they  are 
usually  smaller,  so  that  they  may  be  developed  within  a 
shorter  time,  to  be  ready  in  large  numbers  for  the  emerg- 
ence of  the  females^ 

CJn  two  families  of  the  Homoptera  and  in  three  of  the 
Orthoptera,  the  males  alone  possess  sound-producing  organs 
in  an  efficient  state.  These  are  used  incessantly  during  the 
breeding-season,  not  only  for  calling  the  females,  but  ap- 
parently for  charming  or  exciting  them  in  rivalry  with 
other  males.  Xo  one  who  admits  the  agency  of  selection 
of  any  kind,  will,  after  reading  the  above  discussion,  dis- 
pute that  these  musical  instruments  have  been  acquired 
through  sexual  selection  J  In  four  other  orders  the  mem- 
bers of  one  sex,  or  more  commonly  of  both  sexes,  are  pro- 
vided with  organs  for  producing  various  sounds,  which  ap- 
parently serve  merely  as  call-notes.  When  both  sexes  are 
thus  provided  the  individuals  which  were  able  to  make  the 
loudest  or  most  continuous  noise  would  gain  partners  before 
those  which  were  less  noisy,  so  that  their  organs  have  proba- 
bly been  gained  through  sexual  selection.  It  is  instructive 
to  reflect  on  the  wonderful  diversity  of  the  means  for  pro- 
ducing sound,  possessed  by  the  males  alone,  or  by  both 
sexes  in  no  less  than  six  orders.  We  thus  learn  how  effectual 
sexual  selection  has  been  in  leading  to  modifications  which 
sometimes,  as  with  the  Homoptera,  relate  to  important 
parts  of  the  organization. 

From  the  reasons  assigned  in  the  last  chapter,  it  is  proba- 
ble that  the  great  horns  possessed  by  the  males  of  many 
Lamellicom,  and  some  other  beetles,  have  been  acquired  as 
ornaments.  From  the  small  size  of  insects  we  are  apt  to 
undervalue  their  appearance.  If  we  could  imagine  a  male 
Chalcosoma(seefig.  16),  with  its  polished  bronzed  coat  of  mail 
and  its  vast  complex  horns,  magnified  to  the  size  of  a 
horse,  or  even  of  a  dog,  it  would  be  one  of  the  most  impos- 
ing animals  in  the  world. 

The  coloring  of  insects  is  a  complex  and  obscure  subject. 
When  the  male  differs  slightly  from  the  female,  and 
neither  are  brilliantly  colored,  it  is  probable  that  the  sexes 


372  THE  DESCENT  OF  MAN. 

have  varied  in  a  slightly  different  manner,  and  that  the 
variations  have  been  transmitted  by  each  sex  to  the  same, 
without  any  benefit  or  evil  thus  accruing.  When  the 
male  is  brilliantly  colored  and  differs  conspicuously  from 
the  female,  as  with  some  dragon-flies  and  many  butterflies, 
it  is  probable  that  he  owes  his  colors  to  sexual  selection, 
while  the  female  has  retained  a  primordial  or  very  ancient 
type  of  coloring,  slightly  modified  by  the  agencies  before 
explained.  But  in  some  cases  the  female  has  apparently 
been  made  obscure  by  variations  transmitted  to  her  alone, 
as  a  means  of  direct  protection;  and  it  is  almost  certain 
that  she  has  sometimes  been  made  brilliant,  so  as  to  imitate 
other  protected  species  inhabiting  the  same  district.  When 
the  sexes  resemble  each  other  and  both  are  obscurely  colored 
there  is  no  doubt  that  they  have  been  in  a  multitude  of 
cases  so  colored  for  the  sake  of  protection.  So  it  is  in  some 
instances  when  both  are  brightly  colored,  for  they  thus  imi- 
tate protected  species,  or  resemble  surrounding  objects  such 
as  flowers;  or  they  give  notice  to  their  enemies  that  they 
are  unpalatable.  In  other  cases  in  which  the  sexes  resem- 
ble each  other  and  are  both  brilliant,  especially  when  the 
colors  are  arranged  for  display,  we  may  conclude  that  they 
have  been  gained  by  the  male  sex  as  an  attraction,  and  have 
been  transferred  to  the  female.  We  are  more  especially  led 
to  this  conclusion  whenever  the  same  type  of  coloration  pre- 
vails throughout  a  whole  group,  and  we  find  that  the  males 
of  some  species  differ  widely  in  color  from  the  females, 
while  others  differ  slightly  or  not  at  all  with  intermediate 
gradations  connecting  these  extreme  states. 

In  the  same  manner  as  bright  colors  have  often  been  par- 
tially transferred  from  the  males  to  the  females,  so  it  has 
been  with  the  extraordinary  horns  of  many  Lamellicorn 
and  some  other  beetles.  So,  again,  the  sound-producing 
organs  proper  to  the  males  of  the  Homoptera  and  Orthop- 
tera  have  generally  been  transferred  in  a  rudimentary,  or 
even  in  a  nearly  perfect  condition,  to  the  females  ;  yet  not 
sufficiently  perfect  to  be  of  any  use.  It  is  also  an  interest- 
ing fact,  as  bearing  on  sexual  selection,  that  the  stridu- 
lating  organs  of  certain  male  Orthoptera  are  not  fully 
developed  until  the  last  moult;  and  that  the  colors  of  cer- 
tain male  dragon-flies  are  not  fully  developed  until  some 
little  time  after  their  emergence  from  the  pupal  state,  and 
when  they  are  ready  to  breed. 


INSECTS,  37S 

Sexual  selection  implies  that  the  more  attractive  indi- 
viduals are  preferred  by  the  opposite  sex  ;  and  as  with 
insects,  when  the  sexes  differ,  it  is  the  male  which,  witli 
some  rare  exceptions,  is  the  more  ornamented,  and  departs 
more  from  the  type  to  which  the  species  belongs;  and  as  it 
is  the  male  which  searches  eagerly  for  the  female,  we  must 
suppose  that  the  females  habitually  or  occasionally  prefer 
the  more  beautiful  males,  and  that  these  have  thus  acquired 
their  beauty.  That  the  females  in  most  or  all  the  orders 
would  have  the  power  of  rejecting  any  particular  male,  is 
probable  from  the  many  singular  contrivances  possessed  by 
the  males,  such  as  great  jaws,  adhesive  cushions,  spines, 
elongated  legs,  etc.,  for  seizing  the  female;  for  these  con- 
trivances show  that  there  is  some  difficulty  in  the  act, 
so  that  her  concurrence  would  seem  necessary.  Judging 
from  what  we  know  of  the  perceptive  powers  and  affections 
of  various  insects,  there  is  no  antecedent  improbability  in 
sexual  selection  having  come  largely  into  play;  but  we  have 
as  yet  no  direct  evidence  on  this  head,  and  some  facts  are 
opposed  to  the  belief.  Nevertheless,  when  we  see  many 
males  pursuing  the  same  female,  we  can  hardly  believe  that 
the  pairing  is  left  to  blind  chance — that  the  female  exerts 
no  choice,  and  is  not  influenced  by  the  gorgeous  colors  or 
other  ornaments  with  which  the  male  is  decorated. 

If  we  admit  that  the  females  of  the  Homoptera  and 
Orthoptera  appreciate  the  musical  tones  of  their  male  part- 
ners, and  that  the  various  instruments  have  been  perfected 
through  sexual  selection,  there  is  little  improbability  in  the 
females  of  other  insects  appreciating  beauty  in  form  or 
color,  and  consequently  in  such  characters  having  been 
thus  gained  by  the  males.  But  from  the  circumstance  of 
color  being  so  variable,  and  from  its  having  been  so  oiten 
modified  for  the  sake  of  protection,  it  is  difficult  to  decide 
in  how  large  a  proportion  of  cases  sexual  selection  has 
played  a  part.  This  is  more  especially  difficult  in  those 
orders,  such  as  Orthoptera,  Hymenoptera,  and  Coleoptera, 
in  which  the  two  sexes  rarely  differ  much  in  color;  for  we 
are  then  left  to  mere  analogy.  With  the  Coleoptera,  how- 
ever, as  before  remarked,  it  is  in  the  great  Lamellicom 
group,  placed  by  some  authors  at  the  head  of  the  order, 
and  in  which  we  sometimes  see  a  mutual  attachment  be- 
tween the  sexes,  that  we  find  the  males  of  some  species  pos- 
sessing weapons  for  sexual  strife,  others  furnished  with 


3'J'4  THE  DESCENT  OP  MAN. 

wonderful  horns,  many  with  stridulating  organs,  and  others 
ornamented  with  splendid  metallic  tints.  Hence  it  seems 
probable  that  all  these  characters  have  been  gained  through 
the  same  means,  namely,  sexual  selection.  With  butterflies 
we  have  the  best  evidence,  as  the  males  sometimes  take 
pains  to  display  their  beautiful  colors;  and  we  cannot  be- 
lieve that  they  would  act  thus,  unless  the  display  was  of 
use  to  them  in  their  courtship. 

When  we  treat  of  birds  we  shall  see  that  they  present  in 
their  secondary  sexual  characters  the  closest  analogy  with 
insects.  Thus  many  male  birds  are  highly  pugnacious,  and 
some  are  furnished  with  special  weapons  for  fighting  with 
their  rivals.  They  possess  organs  which  are  used  during 
the  breeding-season  for  producing  vocal  and  instrumental 
music.  They  are  frequently  ornamented  with  combs, 
horns,  wattles  and  plumes  of  the  most  diversified  kinds, 
and  are  decorated  with  beautiful  colors,  all  evidently  for 
the  sake  of  display.  We  shall  find  that,  as  with  insects, 
both  sexes  in  certain  groups  are  equally  beautiful,  and  are 
equally  provided  with  ornaments  which  are  usually  confined 
to  the  male  sex.  In  other  groups  both  sexes  are  equally 
plain-colored  and  unornamented.  Lastly,  in  some  few 
anomalous  cases  the  females  are  more  beautiful  than  the 
males.  We  shall  often  find,  in  the  same  group  of  birds, 
every  gradation  from  no  difference  between  the  sexes  to  an 
extreme  difference.  We  shall  see  that  female  birds,  like 
female  insects,  often  possess  more  or  less  plain  traces  or 
rudiments  of  characters  which  properly  belong  to  the  males 
and  are  of  use  only  to  them.  The  analogy,  indeed,  in  all 
these  respects  between  birds  and  insects  is  curiously  close. 
Whatever  explanation  applies  to  the  one  class  probably 
applies  to  the  other;  and  this  explanation,  as  we  shall  here- 
after attempt  to  show  in  further  detail,  is  sexual  selection. 


FtSHES,  375 


CHAPTEE  XIL 

SECONDARY   SEXUAL  CHARACTERS  OF  FISHES, 
AMPHIBIAJs^S   AIs^D    REPTILES. 

Fishes  :  Courtship  and  battles  of  the  males  —  Larger  size  of  the 
females  —  Males,  bright  colors  and  ornamental  appendages ; 
other  strange  characters  —  Colors  and  appendages  acquired  by 
the  males  during  the  breeding-season  alone — Fishes  with  both 
sexes  brilliantly  colored — Protective  colors — The  less  conspicu- 
ous colors  of  the  female  cannot  be  accounted  for  on  the  principle 
of  protection — Male  fishes  building  nests  and  taking  charge  of 
the  ova  and  young.  Amphibians:  Differences  in  structure  and 
color  between  the  sexes — Vocal  organs.  Reptiles  :  Chelonians 
— Crocodiles — Snakes,  colors  in  some  cases  protective — Lizards, 
battles  of  —  Ornamental  appendages — Strange  differences  in 
structure  between  the  sexes — Colors — Sexual  differences  almost 
as  great  as  with  birds. 

We  have  now  arrived  at  the  great  sub-kingdom  of  the 
Vertebrata,  and  will  commence  with  the  lowest  class,  that 
of  fishes.  The  males  of  Plagiostomous  fishes  (sharks,  rays) 
and  of  Chimaeroid  fishes  are  provided  with  claspers  which 
serve  to  retain  the  female,  like  the  various  structures 
possessed  by  many  of  the  lower  animals.  Besides  the 
claspers,  the  males  of  many  rays  have  clusters  of  strong 
sharp  spines  on  their  heads  and  several  rows  along  "the 
upper  outer  surface  of  their  pectoral  fins."  These  are 
present  in  the  males  of  some  species,  which  have  other 
parts  of  their  bodies  smooth.  They  are  only  temporarily 
developed  during  the  breeding-season  ;  and  Dr.  (lunther 
suspects  that  they  are  brought  into  action  as  prehensile 
organs  by  the  doubling  inward  and  downward  of  the  two 
sides  of  the  body.  It  is  a  remarkable  fact  that  the  females 
and  not  the  males  of  some  species,  as  of  Raia  clavata,  have 
their  backs  studded  with  large  hook-formed  spines.* 

The  males  alone  of  the  capelin  {Mallotus  villosiis,  one  of 

*Yarrell's  "Hist,  of  British  Fishes,"  vol.  ii,  1836,  pp.  417,  425, 
436.  Dr.  Giinther  informs  me  that  the  spines  in  R.  clavata  are 
peculiar  to  the  female. 


376  "TSE  DESCENT  OF  MAN. 

Salmonidae)  are  provided  with  a  ridge  of  closely-set,  brush- 
like scales,  by  the  aid  of  which  two  males,  one  on  each  side, 
hold  the  female,  while  she  runs  with  great  swiftness  on 
the  sandy  beach  and  there  deposits  her  spawn.*  The 
widely  distinct  Mo?iaca?ithus  scopas  presents  a  somewhat 
analogous  structure.  The  male,  as  I)r.  Giinther  informs 
me,  has  a  cluster  of  stiff,  straight  spines,  like  those  of  a 
comb,  on  the  sides  of  the  tail  ;  and  these  in  a  specimen 
six  inches  long  were  nearly  one  and  a  half  inches  in 
length;  the  female  has  in  the  same  place  a  cluster  of  bristles, 
which  may  be  compared  with  those  of  a  toothbrush.  In 
another  species,  M.  peronii,  the  male  has  a  brush  like  that 
possessed  by  the  female  of  the  last  species,  while  the  sides 
of  the  tail  in  the  female  are  smooth.  In  some  other 
species  of  the  same  genus  the  tail  can  be  perceived  to 
be  a  little  roughened  in  the  male  and  perfectly  smooth  in 
the  female;  and  lastly  in  others,  both  sexes  have  smooth 
sides. 

The  males  of  many  fish  fight  for  the  possession  of  the 
females.  Thus  the  male  stickleback  ( Gasterosteus  leiurus) 
has  been  described  as  '^  mad  with  delight "  when  the  female 
comes  out  of  her  hiding-place  and  surveys  the  nest  which 
he  has  made  for  her.  "  He  darts  round  her  in  every  direc- 
tion, then  to  his  accumulated  materials  for  the  nest,  then 
back  again  in  an  instant;  and  as  she  does  not  advance  he 
endeavors  to  push  her  with  his  snout,  and  then  tries  to  pull 
her  by  the  tail  and  side-spine  to  the  nest.^^f  The  males  are 
said  to  be  polygamists;  J  they  are  extraordinarily  bold  and 
pugnacious,  while  ^'the  females  are  quite  pacific."  Their 
battles  are  at  times  desperate;  *^for  these  puny  combatants 
fasten  tight  on  each  other  for  several  seconds,  tumbling 
over  and  over  again,  until  their  strength  appears  completely 
exhausted."  AVith  the  rough-tailed  stickleback  (G.  tracliu- 
rus)  the  males  while  fighting  swim  round  and  round  each 
other,  biting  and  endeavoring  to  pierce  each  other  with 
their  raised  lateral  spines.  The  same  writer  adds,§  **^  the 
bite  of  these  little  furies  is  very  severe.    They  also  use  their 

*"The  American  Naturalist,"  April,  1871,  p.  119. 
f  See  Mr.  R.  Warington's  interesting  articles  in  "  Annals  and  Mag. 
of  Nat.  Hist.,"  Oct.,  1852,  and  Nov.,  1855. 
I  Noel  Humphreys,  "  River  Gardens,"  1857. 
§  Loudon's  "  Mag.  of  Nat.  History,"  vol.  iii,  1830,  p.  331. 


FISHES.  37'J' 

lateral  spines  with  such  fatal  effect  that  I  have  seen  one 
during  a  battle  absolutely  rip  his  opponent  quite  open,  so 
that  he  sank  to  the  bottom  and  died/'  When  a  fish  is  con- 
quered, ^'  his  gallant  bearing  forsakes  him;  his  gay  colors 
fade  away;  and  he  hides  his  disgrace  among  his  peaceable 
companions,  but  is  for  some  time  the  constant  object  of  his 
conqueror's  persecution.'' 

The  male  salmon  is  as  pugnacious  as  the  little  stickle- 
back; and  so  is  the  male  trout,  as  I  hear  from  Dr.  Giinther. 
Mr.  Shaw  saw  a  violent  contest  between  two  male  salmon 
which  lasted  the  whole  day;  and  Mr.  R.  Buist,  Superin- 
tendent of  Fisheries,  informs  me  that  he  has  often  watched 
from  the  bridge  at  Perth  the  males  driving  away  their 
rivals  while  the  females  were  spawning.  The  males  ^'^are 
constantly  fighting  and  tearing  each  other  on  the  spawning- 
beds,  and  many  so  injure  each  other  as  to  cause  the  death 
of  numbers,  many  being  seen  swimming  near  the  banks  of 
the  river  in  a  state  of  exhaustion,  and  apparently  in  a 
dying  state."  *  Mr.  Buist  informs  me  that  in  June,  1868, 
the  keeper  of  the  Stormontfield  Breeding-Ponds  visited  the 
northern  Tyne  and  found  about  300  dead  salmon,  all  of 
which  with  one  exception  were  males;  and  he  was  convinced 
that  they  had  lost  their  lives  by  fighting. 

The  most  curious  point  about  the  male  salmon  is  that 
during  the  breeding-season,  besides  a  light  change  in  color, 
"the  lower  jaw  elongates,  and  a  cartilaginous  pro- 
jection turns  upward  from  the  point,  which,  when  the 
jaws  are  closed,  occupies  a  deep  cavity  between  the  inter- 
maxillary bones  of  the  upper  jaw."t  (Figs.  27  and  28.) 
In  our  salmon  this  change  of  structure  lasts  only  during 
the  breeding-season;  but  in  the  Salmo  lycaodon  of  North- 
western America  the  change,  as  Mr.  J.  K.  Lord  |  believes, 
is  permanent  and  best  marked  in  the  older  males  which  have 
previously  ascended  the  rivers.  In  these  old  males  the 
jaw  becomes  developed  into  an  immense  hook-like  projec- 
tion and  the  teeth  grow  into  regular  fangs,  often  more  than 

*"The  Field,"  June  29,  1867.  For  Mr.  Shaw's  statement,  see 
"  Edinburgh  Review,"  1843.  Another  experienced  observer  (Scrope's 
"Days  of  Salmon  Fishing,"  p.  60)  remarks  that  like  the  stag,  the 
male  would,  if  he  could,  keep  all  other  males  away. 

f  Yarrell,  "History  of  British  Fishes,"  vol.  ii,  1836,  p.  10. 

%  ♦'  The  Naturalist  in  Vancouver's  Island,"  vol.  i,  1866,  p.  54. 


378  THE  DE8GENT  OF  MAN. 

half    an  inch   in  length.      With   the   European   salmon, 
according  to  Mr.  Lloyd,*  the  temporary  hook-like  structure 


Fig.  27.    Head  of  male  common  salmon  (Salmo  solar)  during  the  breeding- 
season. 

[This  drawing,  as  well  as  all  the  others  in  the  present  chapter,  have  been  exe- 
cuted by  the  well-known  artist,  Mr.  G.  Ford,  from  specimens  in  the  British 
Museum,  under  the  kind  superintendence  of  Dr.  Gunther.] 

serves  to  strengthen  and  protect  the  jaws,  when  one  male 
charges  another  with  wonderful  violence;  but  the  greatly 
developed  teeth  of  the  male  American  salmon  may  be  com- 

*  "Scandinavian  Adventures,"  vol.  i,  1854,  pp.  100,  104. 


FISHES.  379 

pared  witli  the  tusks  of  many  male  mammals,  aiid  they 
indicate  an  offensive  rather  than  a  protective  purpose. 

The  salmon  is  not  the  only  fish  in  which  the  teeth  differ 
in  the  two  sexes;  as  this  is  the  case  with  many  rays.     In 


Fig.  28.  Head  of  female  salmon. 

the  thornback  {Raia  Clavata)  the  adult  male  has  sharp, 
pointed  teeth,  directed  backward,  while  those  of  the  female 
are  broad  and  flat,  and  form  a  pavement;  so  that  these 
teeth  differ  in  the  two  sexes  of  the  same  species  more  than 
is  usual  in  distinct  genera  of  the  same  family.  The  teeth 
of  the  male  become  sharp  only  when  he  is  adult;  while 
young  they  are  broad  and  flat  like  those  of  the  female.    As 


380  THE  DESCENT  OF  MAN. 

so  frequently  occurs  with  secondary  sexual  characters,  both 
sexes  of  some  species  of  rays  (for  instance  R.  batis),  when 
adult,  possess  sharp,  pointed  teeth;  and  here  a  character, 
proper  to  and  primarily  gained  by  the  male,  appears  to  have 
been  transmitted  to  the  offspring  of  both  sexes.  The  teeth 
are  likewise  pointed  in  both  sexes  of  R.  maculata,  but  only 
when  quite  adult;  the  males  acquiring  them  at  an  earlier 
age  than  the  females.  AVe  shall  hereafter  meet  with  anal- 
ogous cases  in  certain  birds,  in  which  the  male  acquires  the 
plumage  common  to  both  sexes  when  adult,  at  a  somewhat, 
earlier  age  than  does  the  female.  With  other  species  of 
rays  the  males  even  when  old  never  possess  sharp  teeth,  and 
consequently  the  adults  of  both  sexes  are  provided  with 
broad,  flat  teeth  like  those  of  the  young,  and  like  those  of 
the  mature  females  of  the  above-mentioned  species.*  As 
the  rays  are  bold,  strong  and  voracio  s  fish,  we  may  suspect 
that  the  males  require  their  sharp  teeth  for  fighting  with 
their  rivals;  but  as  they  possess  many  parts  modified  and 
adapted  for  the  prehension  of  the  female,  it  is  psssible  that 
their  teeth  may  be  us$d  for  this  purpose. 

In  regard  to  size,  M.  Carbonnierf  maintains  that  the 
female  of  almost  all  fishes  is  larger  than  the  male;  and  Dr. 
Giinther  does  not  know  of  a  single  instance  in  which  the 
male  is  actually  larger  than  the  female.  With  some 
Cyprinodonts  the  male  is  not  even  half  as  large.  As  in 
many  kinds  of  fishes  the  males  habitually  fight  together,  it 
is  surprising  that  they  have  not  generally  become  larger 
and  stronger  than  the  females  through  the  eifects  of  sexual 
selection.  The  males  suffer  from  their  small  size,  for, 
according  to  M.  Carbonnier,  they  are  liable  to  be  devoured 
by  the  females  of  their  own  species  when  carnivorous,  and 
no  doubt  by  other  species.  Increased  size  must  be  in  some 
manner  of  more  importance  to  the  females  than  strength 
and  size  are  to  the  males  for  fighting  with  other  males; 
and  this  perhaps  is  to  allow  of  the  production  of  a  vast 
number  of  ova. 

In  many  species  the  male  alone  is  ornamented  with 
bright  colors;  or  these  are  much  brighter  in  the  male  than 
the  female.     The  male,  also,   is  sometimes  provided  with 

*  See  Yarrell's  account  of  the  rays  in  bis  "  Hist,  of  British  Fishes,'* 
vol.  ii,  1836,  p.  416,  with  an  excellent  figure,  and  pp.  422,  432. 

f  As  quoted  in  "  The  Farmer,"  1868,  p.  369. 


FISHES. 


381 


appendages  which  appear  to  be  of  no  more  use  ix)  him  for 
the  ordinary  purposes  of  life  than  are  the  tail  feathers  to 
the  peacock.  I  am  indebted  for  most  of  the  following 
facts  to  the  kindness  of  Dr.  Giinther.  There  is  reason 
to  suspect  that  many  tropical  fishes  differ  sexually  in  color 
and  structure;  and  there  are  some  striking  cases  with  our 
British  fishes.  The  male  Callio^iymns  lyra  has  been  called 
the  gemmeous  dragonet  ^^  from  its  brilliant  gem-like  colors/' 


Fig.  29.    Callionymus  IjTa     Upper  figure,  male ;  lower  figure,  female. 
N.  B.— The  lower  figure  is  more  reduced  than  the  upper. 

When  fresh  caught  from  the  sea  the  body  is  yellow  of 
various  shades,  striped  and  spotted  with  vivid  blue  on  the 
head;  the  dorsel  fins  are  pale  brown  with  dark  longitudinal 
bands;  the  ventral,  caudal  and  anal  fins  being  bluish-black. 
The  female,  or  sordid  dragonet,  was  considered  by  Lin- 
naeus and  by  many  subsequent  naturalists  as  a  distinct 
species;  it  is  of  a  ding}^  reddish-brown  with  the  dorsal  fin 
brown  and  the  other  fins  white.  The  sexes  differ  also  in 
the  proportional  size  of  the  head  and  mouth  and  in  the 
position  of  the  eyes;*  but  the  most  striking  difference  is 
the  extraordinary  elongation  in  the  male  (fig.  29)  of  the 

*I  have  drawn    np    this    description    from    Yarrell's    "British 
Fishes,"  vol.  i,  1836,  pp.  261,  266. 


382  THE  DESCENT  OF  MAN, 

dorsal  fin.  Mr.  W.  Saville  Kent  remarks  that  this  *^  sin- 
gular appendage  appears  from  my  observations  of  the 
species  in  confinement  to  be  subservient  to  the  same  end 
as  the  wattles,  crests  and  other  abnormal  adjuncts  of  the 
male  in  gallinaceous  birds  for  the  purpose  of  fascinating 
their  mates.  ^^*  The  young  males  resemble  the  adult 
females  in  structure  and  color.  Throughout  the  genus 
Callionymusf  the  male  is  generally  much  more  brightly 
spotted  than  the  female,  and  in  several  species,  not  only 
the  dorsal,  but  the  anal  fin  is  much  elongated  in  the  males. 
The  male  of  the  Cottus  scorpius,  or  sea-scorpion,  is 
slenderer  and   smaller  than  the  female.     There  is  also  a 

freat  difference  in  color  between  them.  It  is  difficult,  as 
[r.  Lloyd  J;  remarks,  "  for  any  one  who  has  not  seen  this 
fish  during  the  spawning  season  when  its  hues  are  brighest 
to  conceive  the  admixture  of  brilliant  colors  with  which  it, 
in  other  respects  so  ill-favored,  is  at  that  time  adorned." 
Both  sexes  of  the  Lahrus  mixtus,  although  very  different 
in  color,  are  beautiful;  the  male  being  orange  with  bright 
blue  stripes  and  the  female  bright  red  with  some  black 
spots  on  the  back. 

In  the  very  distinct  family  of  the  Cyprinodontidae — 
inhabitants  of  the  fresh  waters  of  foreign  lands — the  sexes 
sometimes  dift'er  much  in  various  characters.  In  the  male 
of  the  Mollienesia  petenensis,%  the  dorsal  fin  is  greatly  de- 
veloped and  is  marked  with  a  row  of  large,  round,  ocellated, 
bright-colored  spots;  while  the  same  fin  in  the  female  is 
smaller,  of  a  different  shape,  and  marked  only  with  irregu- 
larly curved  brown  spots.  In  the  male  the  basal  margin  of 
the  anal  fin  is  also  a  little  produced  and  dark  colored.  In 
the  male  of  an  allied  form,  the  Xiphopliorus  Heller ii  (fig. 
80),  the  inferior  margin  of  the  caudal  fin  is  developed  into 
a  long  filament,  which,  as  I  hear  from  Dr.  Giinther,  is 
striped  with  bright  colors.  This  filament  does  not  contain 
any  muscles,  and  apparently  cannot  be  of  any  direct  use  to 
the  fish.     As  in  the  case  of  the  Callionymus,  the  males 

♦  "  Nature,"  July,  1873,  p.  264. 

f  ■*  Catalogue  of  Acanth.  Fishes  in  tlie  British  Museum,"  by  Dr. 
Ountlier,  X61,  pp.  138-151. 

X  "Game  Birds  of  Sweden,"  etc.,  1867,  p.  466. 

§  With  respect  to  this  and  the  following  species  I  am  indebted  to 
Dr.  Giinther  for  information;  see  also  his  paper  on  the  "  Fishes  of 
Teptrfi^  America,"  in  "Transact.  Zoolog.  Soc,"  vol.  vi,  1868,  p.  485, 


FISHES.  383 

while  young  resemble  the  adult  females  in  color  and  struct- 
ure. Sexual  differences  such  as  these  may  be  strictly  com- 
pared with  those  which  are  so  frequent  with  gallinaceous 
birds.* 

In  a  siluroid  fish,  inhabiting  the  fresh  waters  of  South 
America,  the  Plecostomus  harl)atus\  (fig.  31),  the  male  has 
its  mouth  and  inter-operculum  fringed  with  a  beard  of  stiff 
hairs,  of  which  the  female  shows  hardly  a  trace.     These 


Fig.  30,    Xiphophoros  Hellerii.    Upper  figure,  male ;  lower  figure,  female. 


hairs  are  of  the  nature  of  scales.  In  another  species  of  the 
same  genus,  soft  flexible  tentacles  project  from  the  front 
part  of  the  head  of  the  male,  which  are  absent  in  the 
female.  These  tentacles  are  prolongations  of  the  true  skin, 
and  therefore  are  not  homologous  with  the  stiff  hairs  of  the 
former  species;  but  it  can  hardly  be  doubted  that  both 
serve  the  same  purpose.  What  this  purpose  may  be  it  is 
difficult  to  conjecture;  ornament  does  not  here  seem  prob- 
able, but  we  can  hardly  suppose  that  stiff  hairs  and  flexible 

*Dr.  Gunther  makes  this  remark;  "Catalogue  of  Fishes  in  the 
British  Museum,"  vol.  iii,  1861,  p.  141. 

f  See  Dr.  Qtlnther  on  this  genus,  in  '•  Proc.  Zoolog.  Soc./'  1868,  p. 


384  THE  DESCENT  OF  MAN, 


FUj.  31.    Plecostomus  barbatus.    Upper  figure,  head  of  male ;  lower  figure, 
female. 


FISHES.  385 

filaments  can  be  useful  in  any  ordinary  way  to  the  males 
alone.  In  that  strange  monster,  the  Chimcera  monstrosa, 
the  male  has  a  hook-shaped  bone  on  the  top  of  the  head, 
directed  forward,  with  its  end  rounded  and  covered  with 
sharp  spines ;  in  the  female  ^^  this  crown  is  altogether 
absent,"  but  what  its  use  may  be  to  the  male  is  utterly 
unknown.* 

The  structures  as  yet  referred  to  are  permanent  in  the 
male  after  he  has  arrived  at  maturity;  but  with  some  Blen- 
nies,  and  in  another  allied  genus,  \  a  crest  is  developed  on 
the  head  of  the  male  only  during  the  breeding  season,  and 
the  body  at  the  same  time  becomes  more  brightly  colored. 
There  can  be  little  doubt  that  this  crest  serves  as  a  tem- 
porary sexual  ornament,  for  the  female  does  not  exhibit  a 
trace  of  it.  In  other  species  of  the  same  genus  both  sexes 
possess  a  crest,  and  in  at  least  one  species  neither  sex  is 
thus  provided.  In  many  of  the  Ohromidag,  for  instance  in 
Geophagus  and  especially  in  Cichla,  the  males,  as  I  hear 
from  Prof.  Agassiz,];  have  a  conspicuous  protuberance  on 
the  forehead  which  is  wholly  wanting  in  the  females  and 
in  the  young  males.  Prof.  Agassiz  adds:  '^I  have  often 
observed  these  fishes  at  the  time  of  spawning  when  the 
protuberance  is  largest,  and  at  other  seasons  when  it  is 
totally  wanting,  and  the  two  sexes  show  no  difference 
whatever  in  the  outline  of  the  profile  of  the  head.  I 
never  could  ascertain  that  it  subserves  any  special  func- 
tion, and  the  Indians  on  the  Amazon  know  nothing  about 
its  use."  These  protuberances  resemble  in  their  periodical 
appearance  the  fleshy  carbuncles  on  the  heads  of  certain 
birds;  but  whether  they  serve  as  ornaments  must  remain  at 
present  doubtful. 

I  hear  from  Prof.  Agassiz  and  Dr.  Giinther  that  the 
males  of  those  fishes  which  differ  permanently  in  color 
from  the  females  often  become  more  brilliant  during 
the  breeding  season.  This  is  likewise  the  case  with  a 
multitude  of  fishes,   the  sexes  of  which  are  identical  in 

*F.  Buckland  in  "  Land  and  Water,"  July,  1868,  p.  377,  with  a 
figure.  Many  other  cases  could  be  added  of  structures  peculiar  to 
the  male,  of  which  the  uses  are  not  known. 

f  Dr.  Giinther,  "  Catalogue  of  Fishes,"  vol.  iii,  pp.  221  and  240. 

1  See  also  **  A  Journey  in  Brazil,"  by  Prof,  and  Mrs.  Agassiz,  1868, 
p.  220.  p 


386  THE  DESCENT  OF  MAN. 

color  at  all  other  seasons  of  the  year.  The  tench,  roach 
and  perch  may  be  given  as  instances.  The  male  salmon 
at  this  season  is  ''  marked  on  the  cheeks  with  orange- 
colored  stripes,  which  give  it  the  appearance  of  a  Labrus, 
and  the  body  partakes  of  a  golden-orange  tinge.  The 
females  are  dark  in  color,  and  are  commonly  called  black- 
fish."*  An  analogous  and  even  greater  change  takes  place 
with  the  Salmo  eriox  or  bull  trout ;  the  males  of  the  char 
{S.  umhla)  are  likewise  at  this  season  rather  brighter  in 
color  than  the  females. f  The  colors  of  the  pike  (Esox 
reticulatus)  of  the  United  States,  especially  of  the  male, 
become,  during  the  breeding-season,  exceedingly  intense, 
brilliant,  and  iridescent.  J  Another  striking  instance  out 
of  many  is  afforded  by  the  male  stickleback  ( Gasterosteus 
leiurus),  which  is  described  by  Mr.  Waringto*n,§  as  being 
then  ^^  beautiful  beyond  description."  The  back  and  eyes 
of  the  female  are  simply  brown  and  the  belly  white.  The 
eyes  of  the  male,  on  the  other  hand,  are  "  of  the  most 
splendid  green,  having  a  metallic  luster  like  the  green 
feathers  of  some  humming-birds.  The  throat  and  belly  are 
of  a  bright  crimson,  the  back  of  an  ashy-green,  and  the 
whole  fish  appears  as  though  it  were  somewhat  translucent 
and  glowed  with  an  internal  incandescence."  After  the 
breeding-season  these  colors  all  change,  the  throat  and 
belly  become  of  a  paler  red,  the  back  more  green,  and  the 
glowing  tints  subside. 

With  respect  to  the  courtship  of  fishes,  other  cases  have 
been  observed  since  the  first  edition  of  this  book  appeared, 
besides  that  already  given  of  the  stickleback.  Mr.  W.  S. 
Kent  says  that  the  male  of  the  Lcihrus  mixtus,  which,  as 
we  have  seen,  differs  in  color  from  the  female,  makes  ^'  a 
deep  hollow  in  the  sand  of  the  tank,  and  then  endeavors  in 
the  most  persuasive  manner  to  induce  a  female  of  the  same 
species  to  share  it  with  him,  swimming  backward  and  for- 
ward between  her  and  the  completed  nest,  and  plainly 
exhibiting  the  greatest  anxiety  for  her  to  follow."  The 
males  of  Cantliarus  lioieatus  become,  during  the  breeding- 

*Yarrell,  "British  Fishes,"  vol.  ii,  1836,  pp.  10,  12,  35. 
f  W.  Thompson,  in  "Annals  and  Mag.  of  Nat,  History,"  vol.  vi, 
1841,  p.  440. 
t"  The  American  Agriculturist,"  1868,  p.  100. 
§  "  Annals  and  Mag.  of  Nat.  Hist.,"  Oct.,  1853. 


FISHES.  387 

season,  of  deep  leaden-black;  they  then  retire  from  the 
shoal,  and  excavate  a  hollow  as  a  nest.  *^  Each  male  now 
mounts  vigilant  guard  over  his  respective  hollow,  and  vig- 
orously attacks  and  drives  away  any  other  fish  of  the  same 
sex.  Toward  hij  companions  of  the  opposite  sex  his  con- 
duct is  far  different;  many  of  the  latter  are  now  distended 
with  spawn,  and  these  he  endeavors  by  all  the  means  in  his 
power  to  lure  singly  to  his  prepared  hollow,  and  there  to 
deposit  the  myriad  ova  with  which  they  are  laden,  which 
he  then  protects  and  guards  with  the  greatest  care."* 

A  more  striking  case  of  courtship,  as  well  as  of  display, 
by  the  males  of  a  Chinese  Macropus  has  been  given  by  M. 
Carbonnier,  who  carefully  observed  these  fishes  under  con- 
finement, f  The  males  are  most  beautifully  colored,  more 
so  than  the  females.  During  the  breeding-season  they  con- 
tend for  the  possession  of  the  females ;  and,  in  the  act  of 
courtship,  expand  their  fins,  which  are  spotted  and  orna- 
mented with  brightly  colored  rays,  in  the  same  manner, 
according  to  M.  Carbonnier,  as  the  peacock.  They 
then  also  bound  about  the  females  with  much  vivacity,  and 
appear  by  ^^'etalage  de  leurs  vives  couleurs  chercher  d 
attirer  Tattention  des  femelles,  lesquelles  ne  paraissaient 
indifferentes  a  ce  manege,  elles  nageaient  avec  une  molle 
lenteur  vers  les  mdles  et  semblaient  se  complaire  dans  leur 
voisinage."  After  the  male  has  won  his  bride  he  makes  a 
little  disk  of  froth  by  blowing  air  and  mucus  out  of  his 
mouth.  He  then  collects  the  fertilized  ova  dropped  by  the 
female  in  his  mouth;  and  this  caused  M.  Carbonnier  much 
alarm,  as  he  thought  that  they  were  going  to  be  devoured. 
But  the  male  soon  deposits  them  in  the  disk  of  froth,  after- 
ward guarding  them,  repairing  the  froth,  and  taking  care 
of  the  young  when  hatched.  I  mention  these  particulars 
because,  as  we  shall  presently  see,  there  are  fishes  the  males 
of  which  hatch  their  eggs  in  their  mouths;  and  those  who 
do  not  believe  in  the  principle  of  gradual  evolution  might 
ask  how  could  such  a  habit  have  originated;  but  the  diffi- 
culty is  much  diminished  when  we  know  that  there  are 
fishes  which  thus  collect  and  carry  the  eggs;  for  if  delayed 
by  any  cause  in  depositing  them,  the  habit  of  hatching 
them  in  their  mouths  might  have  been  acquired. 

*  *' Nature,"  May,  1873,  p.  25. 

I** Bull,  de  la  Soc.  d'Acclimat.,"  Paris,  July,  1869,  and  Jan.  1870, 


388  THE  DESCENT  OF  MAN. 

To  return  to  our  more  immediate  subject.  The  case 
stands  thus;  female  fishes,  as  far  as  I  can  learn,  never  will- 
ingly spawn  except  in  the  presence  of  the  males;  and  the 
males  never  fertilize  the  ova  except  in  the  presence  of  the 
females.  The  males  fight  for  the  possession  of  the  females. 
In  many  species  the  males  while  young  resemble  the  females 
in  color;  but  when  adult  become  much  more  brilliant,  and 
retain  their  colors  throughout  life.  In  other  species  the 
males  become  brighter  than  the  females  and  otherwise  more 
highly  ornamented,  only  during  the  season  of  love.  The 
males  sedulously  court  the  females,  and  in  one  case,  as  we 
have  seen,  take  pains  in  displaying  their  beauty  before 
them.  Can  it  be  believed  that  they  would  thus  act  to  no 
purpose  during  their  courtship?  And  this  would  be  the  case 
unless  the  females  exert  some  choice  and  select  those  males 
which  please  or  excite  them  most.  If  the  female  exerts 
such  choice,  all  the  above  facts  on  the  ornamentation  of 
the  males  become  at  once  intelligible  by  the  aid  of  sexual 
selection. 

We  have  next  to  inquire  whether  this  view  of  the  bright 
colors  of  certain  male  fishes  having  been  acquired  through 
sexual  selection  can,  through  the  law  of  the  equal  trans- 
mission of  characters  to  both  sexes,  be  extended  to  those 
groups  in  which  the  males  and  females  are  brilliant  in  the 
same,  or  nearly  the  same,  degree  and  manner.  In  such  a 
genus  as  Labrus,  which  includes  some  of  the  most  splendid 
fislies  in  the  world — for  instance,  the  Peacock  Labrus  {L. 
pavo),  described,*  with  pardonable  exaggeration,  as  formed 
of  polished  scales  of  gold,  incrusting  lapis-lazuli,  rubies, 
sapphires,  emeralds  and  amethysts — we  may,  with  much 
probability,  accept  this  belief,  for  we  have  seen  tliat  the 
sexes  in  at  least  one  species  of  the  genus  differ  greatly  in 
color.  Witii  some  fishes,  as  with  many  of  the  lowest  ani- 
mals, splendid  colors  may  be  the  direct  result  of  the  nature 
of  their  tissues  and  of  the  surrounding  conditions,  without 
the  aid  of  selection  of  any  kind.  The  gold-fish  ( Cyprinus 
auratus),  judging  from  the  analogy  of  the  golden  variety 
of  the  common  carp,  is  perhaps  a  case  in  point,  as  it  may 
owe  its  splendid  colors  to  a  single  abrupt  variation,  due  to 
the  conditions  to  which  this  fish  has  been  subjected  under 

*  Bory  de  Saint  Vincent,  in 
1826,  p.  151. 


Pishes.  38d 

confinement.  It  is,  however,  more  probable  that  these 
colors  have  been  intensified  through  artificial  selection,  as 
this  species  lias  been  carefully  bred  in  China  from  a  remote 
period.*  Under  natural  conditions  it  does  not  seem  prob- 
able that  beings  so  highly  organized  as  fishes,  and  which 
live  under  such  complex  relations,  should  become  brilliantly 
colored  without  suffering  some  evil  or  receiving  some  bene- 
fit from  so  great  a  change,  and  consequently  without  the 
intervention  of  natural  selection. 

What,  then,  are  we  to  conclude  in  regard  to  the  many 
fishes,  both  sexes  of  which  are  splendidly  colored?  Mr. 
Wallace  f  believes  that  the  species  which  frequent  reefs, 
where  corals  and  other  brightly-colored  organisms  abound, 
are  brightly  colored  in  order  to  escape  detection  by  their 
enemies;  but  according  to  my  recollection  they  were  thus 
rendered  highly  conspicuous.  In  the  fresh  waters  of  the 
tropics  there  are  no  brilliantly-colored  corals  or  other 
organisms  for  the  fishes  to  resemble;  yet  many  Species  in 
the  Amazons  are  beautifully  colored,  and  many  of  the  car- 
nivorous Cyprinidae  in  India  are  ornamented  with  '^bright 
longitudinal  lines  of  various  tints."' J;  Mr.  McClelland,  in 
describing  these  fishes,  goes  so  far  as  to  suppose  that  '^  the 
peculiar  brilliancy  of  their  colors  ^^  serves  as  ^' a  better 
mark  for  king-fishers,  terns,  and  other  birds  which  are 
destined  to  keep  the  number  of  these  fishes  in  check;"  but 
at  the  present  day  few  naturalists  will  admit  that  any 
animal  has  been  made  conspicuous  as  an  aid  to  its  own 
destruction.  It  is  possible  that  certain  fishes  may  have 
been  rendered  conspicuous  in  order  to  warn  birds  and  beasts 
of  prey  that  they  were  unpalatable,  as  explained  when 
treating  of  caterpillars;  but  it  is  not,  I  believe,  known  that 

*  Owing  to  some  remarks  on  this  subject  made  in  my  work  "  On 
the  Variation  of  Animals  under  Domestication,"  Mr.  W.  F.  Mayers 
("Chinese  Notes  and  Queries,"  Aug.  1868,  p.  123)  has  searched  the 
ancient  Chinese  encyclopedias.  He  finds  that  gold-fish  were  first 
reared  in  confinement  during  the  Sung  Dynasty  which  commenced 
A.  D.  960.  In  the  year  1129  these  fishes  abounded.  In  another 
place  it  is  said  that  since  the  year  1548  there  has  been  "  produced  at 
Hangchow's  a  variety  called  the  fire-fish,  from  its  intensely  red  color. 
It  is  universally  admired  and  there  is  not  a  household  where  it  is  not 
cultivated,  in  rivalry  as  to  its  color,  and  as  a  source  of  profit." 

f  "  Westminster  Review,"  July,  1867,  p.  7. 

X  "  Indian  Cyprinidae,"  by  Mr.  M'Clelland,  "  Asiatic  Researches,'* 
vol.  xix,  part  ii,  1839,  p.  230. 


390  THE  DESCENT  OF  MAN. 

any  fish,  at  least  any  fresh-water  fish,  is  rejected  from 
being  distasteful  to  fish-devouring  animals.  On  the  whole, 
the  most  probable  view  in  regard  to  the  fishes,  of  which 
both  sexes  are  brilliantly  colored,  is  that  their  colors  were 
acquired  by  the  males  as  a  sexual  ornament,  and  were 
transferred  equally,  or  nearly  so,  to  the  other  sex. 

We  have  now  to  consider  whether,  when  the  male  differs 
in  a  marked  manner  from  the  female  in  color  or  in  other 
ornaments,  he  alone  has  been  modified,  the  variations  being 
inherited  by  his  male  offspring  alone ;  or  whether  the 
female  has  been  specially  modified  and  rendered  inconspicu- 
ous for  the  sake  of  protection,  such  modifications  being 
inherited  only  by  the  females.  It  is  impossible  to  doubt 
that  color  has  been  gained  by  many  fishes  as  a  protection;  no 
one  can  examine  the  speckled  upper  surface  of  a  flounder 
and  overlook  its  resemblance  to  the  sandy  bed  of  the  sea  on 
which  it  lives.  Certain  fishes,  moreover,  can  through  the 
action  of  the  nervous  system  change  their  colors  in  adapta- 
tion to  surrounding  objects,  and  that  within  a  short  time.* 
One  of  the  most  striking  instances  ever  recorded  of  an 
animal  being  protected  by  its  color  (as  far  as  it  can  be 
Judged  of  in  preserved  specimens),  as  well  as  by  its  form, 
is  that  given  by  Dr.  Giintherf  of  a  pipe-fish,  which,  with 
its  reddish  streaming  filaments,  is  hardly  distinguishable 
from  the  sea-weed  to  which  its  clings  with  its  prehensile 
tail.  But  the  question  now  under  consideration  is  whether 
the  females  alone  have  been  modified  for  this  object.  We 
can  see  that  one  sex  will  not  be  modified  through  natural 
selection  for  the  sake  of  protection  more  than  the  other, 
supposing  both  to  vary,  unless  one  sex  is  exposed  for  a 
longer  period  to  danger,  or  has  less  power  of  escaping  from 
such  danger  than  the  other;  and  it  does  not  appear  that 
with  fishes  the  sexes  differ  in  these  respects.  As  far  as 
there  is  any  difference  the  males,  from  being  generally 
smaller  and  from  wandering  more  about,  are  exposed  to 
greater  danger  than  the  females;  and  yet  when  the  sexes 
differ  the  males  are  almost  always  the  more  conspicuously 
colored.  The  ova  are  fertilized  immediately  after  being 
deposited;  and  when  this  process  lasts  for  several  days,  as 
in  the  case  of  the  salmon,  J  the  female  during  the  whole 

*G.  Pouchet,  L'Institut,  Nov.  1,  1871.  p.  134. 
•|-"Proc.  Zoolog.  Soc,"  1865,  p.  327,  pi.  xiv  and  xv. 
|Yarrell,  '*  British  Fishes/'  vol.  ii,  p.  11. 


FtSHES.  391 

time  is  attended  by  the  male.  ,  After  the  ova  are  fertilized 
they  are,  in  most  cases,  left  unprotected  by  both  parents, 
so  that  the  males  and  females,  as  far  as  oviposition  is  con- 
cerned, are  equally  exposed  to  danger,  and  both  are  equally 
important  for  the  production  of  fertile  ova;  consequently 
the  more  or  less  brightly  colored  individuals  of  either 
sex  would  be  equally  liable  to  be  destroyed  or  preserved, 
and  both  would  have  an  equal  influence  on  the  colors  of 
their  offspring. 

Certain  fishes,  belonging  to  several  families,  make  nests, 
and  some  of  them  take  care  of  their  young  when  hatched. 
Both  sexes  of  the  bright-colored  Crenilahrus  massa  and 
melops  work  together  in  building  their  nests  with  sea-weed, 
shells,  etc.*  But  the  males  of  certain  fishes  do  all  the 
work  and  afterward  take  exclusive  charge  of  the  young. 
This  is  the  case  with  the  dull-colored  gobies,  f  in  which  the 
sexes  are  not  known  to  differ  in  color,  and  likewise  with 
the  sticklebacks  (Gasterosteus),  in  which  the  males  become 
brilliantly  colored  during  the  spawning  season.  The  male 
of  the  smooth-tailed  stickleback  ( G.  lehirus)  performs  the 
duties  of  a  nurse  with  exemplary  care  and  vigilance  during 
a  long  time,  and  is  continually  employed  in  gently  leading 
back  the  young  to  the  nest  when  they  stray  too  far.  He 
courageously  drives  away  all  enemies,  including  the  females 
of  his  own  species.  It  would  indeed  be  no  small  relief  to 
the  male  if  the  female  after  depositing  her  eggs  were 
immediately  devoured  by  some  enemy,  for  he  is  forced 
incessantly  to  drive  her  from  the  nest.  J 

The  males  of  certain  other  fishes  inhabiting  South  Amer- 
ica and  Ceylon,  belonging  to  two  distinct  orders,  have  the 
extraordinary  habit  of  hatching  within  their  mouths,  or 
branchial  cavities,  the  eggs  laid  by  the  females.  §  I  am 
informed  by  Prof.  Agassiz  that  the  males  of  the  Amazonian 

*  According  to  the  observations  of  M.  Gerbe;  see  Gunther's 
"  Record  of  Zoolog.  Literature,"  1865,  p.  194. 

f  Cuvier,  "  Regne  Animal,"  vol.  ii,  1829,  p.  242. 

X  See  Mr.  Warington's  most  interesting  description  of  the  habits  of 
the  Gasterosteus  leiunis  in  "  Annals  and  Mag.  of  Nat.  Hist.,"  Nov., 
1855. 

§Prof.  Wyman,  in  ''Proc.  Boston  Soc.  of  Nat.  Hist.,"  Sept.  15, 
1857.  Also  Prof.  Turner,  in  "Journal  of  Anatomy  and  Phys.," 
Nov.  1,  1866,  p.  78.     Dr.   Gunther  has  likewise  described  other 


392  TBE  DESCENT  OF  MAN. 

species  which  follow  this  liabit,  *'  not  only  are  generally 
brigliter  than  the  females,  but  the  difference  is  greater  at 
the  spawning-season  than  at  any  other  time."  The  species 
of  Geophagus  act  in  the  same  manner;  and  in  this  genus,  a 
conspicuous  protuberance  becomes  developed  on  the  fore- 
head of  the  males  during  the  breeding-season.  With  the 
various  species  of  Chromids,  as  Prof.  Agassiz  likewise 
informs  me,  sexual  differences  in  color  may  be  observed, 
"  whether  they  lay  their  eggs  in  the  water  among  aquatic 
plants  or  deposit  them  in  holes,  leaving  them  to  come  out 
without  further  care;  or  build  shallow  nests  in  the  river 
mud,  over  which  they  sit,  as  our  Pomotis  does.  It  ought 
also  to  be  observed  that  these  sitters  are  among  the  bright- 
est species  in  their  respective  families;  for  instance,  Hygro- 
gonus  is  bright  green  with  large  black  ocelli,  encircled 
with  the  most  brilliant  red."  Whether  with  all  the  species 
of  Chromids  it  is  the  male  alone  which  sits  on  the  eggs  is 
not  known.  It  is,  however,  manifest  that  the  fact  of  the 
eggs  being  protected  or  unprotected  by  the  parents,  has  had 
little  or  no  influence  on  the  differences  in  color  between  the 
sexes.  It  is  further  manifest  in  all  the  cases  in  which  the 
males  take  exclusive  charge  of  the  nests  and  young,  that 
the  destruction  of  the  brighter- colored  males  would  be  far 
more  influential  on  the  character  of  the  race  than  the 
destruction  of  the  brighter-colored  females;  for  the  death 
of  the  male  during  the  period  of  incubation  or  nursing 
would  entail  the  death  of  the  young,  so  that  they  could  not 
inherit  his  peculiarities;  yet  in  many  of  these  very  cases 
the  males  are  more  conspicuously  colored  than  the  females. 
In  most  of  the  Lophobranchii  (Pipe-fish,  Hippocampi, 
etc.)  the  males  have  either  marsupial  sacks  or  hemispherical 
depressions  on  the  abdomen,  in  which  the  ova  laid  by  the 
female  are  hatched.  The  males  also  show  great  attachment 
to  their  young.*  The  sexes  do  not  commonly  differ  much 
in  color;  but  Dr.  Giinther  believes  that  the  male  Hippo- 
campi are  rather  brighter  than  the  females.  The  genus 
Solenostoma,  however,  offers  a  curious  exceptional  case,t 
for  the  female  is  much  more  vividly  colored  and  spotted 

*  Yarrell.  "  Hist,  of  British  Fishes,"  vol.  ii,  1836,  pp.  329,  338. 

f  Dr.  Giinther,  since  publishing  an  account  of  this  species  in  "  The 
Fishes  of  Zanzibar,"  by  Col.  Playfair,  1866,  p.  137,  has  re-examined 
the  specimens  and  has  given  me  the  above  information. 


FISHES.  393 

than  the  male,  and  she  alone  has  a  marsupial  sack  and 
hatches  the  eggs;  so  that  the  female  of  Solenostoma  differs 
from  all  other  Lophobranchii  in  this  latter  respect,  and 
from  almost  all  other  fishes,  in  being  more  brightly  colored 
than  the  male.  It  is  improbable  that  this  remarkable 
double  inversion  of  character  in  the  female  should  be 
an  accidental  c  .ncidence.  As  the  males  of  several  fishes, 
which  take  exclusive  charge  of  the  eggs  and  young,  are 
more  brightly  colored  than  the  females,  and  as  here  the 
female  Solenostoma  takes  the  same  charge  and  is  brighter 
than  the  male,  it  might  be  argued  that  the  conspicuous  colors 
of  that  sex  which  is  the  more  important  of  the  two  for  the 
welfare  of  the  offspring,  must  be  in  some  manner  pro- 
tective. But  from  the  large  number  of  fishes,  of  which  the 
males  are  either  permanently  or  periodically  brighter  than 
the  females,  but  whose  life  is  not  at  all  more  important  for 
the  welfare  of  the  species  than  that  of  the  female,  this 
view  can  hardly  be  maintained.  When  we  treat  of  birds 
we  shall  meet  Avith  analogous  cases,  where  there  has  been  a 
complete  inversion  of  the  usual  attributes  of  the  two  sexes, 
and  we  shall  tlien  give  what  appears  to  be  the  probable 
explanation,  namely,  that  the  males  have  selected  the  more 
attractive  females,  instead  of  the  latter  having  selected,  in 
accordance  with  the  usual  rule  throughout  the  animal 
kingdom,  the  more  attractive  males. 

On  the  whole  we  may  conclude,  that  with  most  fishes,  in 
which  the  sexes  differ  in  color  or  in  other  ornamental  char- 
acters, the  males  originally  varied,  with  their  variations 
transmitted  to  the  same  sex,  and  accumulated  through 
sexual  selection  by  attracting  or  exciting  the  females.  In 
many  cases,  however,  such  characters  have  been  transferred, 
either  partially  or  completely,  to  the  females.  In  otlier 
cases,  again,  both  sexes  have  been  colored  alike  for  the  sake 
of  protection;  but  in  no  instance  does  it  appear  that  the 
female  alone  has  had  her  colors  or  other  characters  specially 
modified  for  this  latter  purpose. 

The  last  point  which  need  be  noticed  is  that  fishes  are 
known  to  make  various  noises,  some  of  which  are  described 
as  being  musical.  Dr.  Dufosse,  who  has  especially  attended 
to  this  subject,  says  tliat  the  sounds  are  voluntarily  pro- 
duced in  several  ways  by  different  fishes;  by  the  friction  of 
the  pharyngeal  bones — by  the  vibration  of  certain  muscles 
attached  to  the  swim-bladder,  which  serves  as  a  resounding 


394  THE  DESCENT  OF  MAN. 

board — and  by  the  vibration  of  the  intrinsic  muscles  of  the 
swim-bladder.  By  this  latter  means  the  Trigla  produces 
pure  and  long-drawn  sounds  which  range  over  nearly  an 
octave.  But  the  most  interesting  case  for  us  is  that  of  two 
species  of  Ophidium,  in  which  the  males  alone  are  provided 
with  a  sound-producing  apparatus,  consisting  of  small  mov- 
able bones,  with  proper  muscles,  in  connection  with  the 
swim-bladder.*  The  drumming  of  the  Umbrinas  in  the 
European  seas  is  said  to  be  audible  from  a  depth  of  twenty 
fathoms;  and  the  fisherman  of  Roclielle  assert  '^^that  the 
males  alone  make  the  noise  during  the  spawning- time;  and 
that  it  is  possible  by  imitating  it  to  take  them  without 
bait."f  From  this  statement,  and  more  especially  from 
the  case  of  Ophidium,  it  is  almost  certain  that  in  this,  the 
lowest  class  of  the  Vertebrata,  as  with  so  many  insects  and 
spiders,  sound-producing  instruments  have,  at  least  in  some 
cases,  been  developed  through  sexual  selection,  as  a  means 
for  bringing  the  sexes  together. 

AMPHIBIAKS. 

Urodela. — I  will  begin  with  the  tailed  amphibians.  The 
sexes  of  salamanders  or  newts  often  differ  much  both  in 
color  and  structure.  In  some  species  prehensile  claws 
are  developed  on  the  fore  legs  of  the  males  during 
the  breeding-season;  and  at  this  season  in  the  male  Triton 
pahnipes  the  hind  feet  are  provided  with  a  swimming-web, 
which  is  almost  completely  absorbed  during  the  winter;  so 
that  their  feet  then  resemble  those  of  the  female.  |  This 
structure  no  doubt  aids  the  male  in  his  eager  search  and 
pursuit  of  the  female.  While  courting  her  he  rapidly 
vibrates  the  end  of  his  tail.  With  our  common  newts 
{Triton  punctatus  and  cristatus)  a  deep,  much  indented 
crest  is  developed  along  the  back  and  tail  of  the  male 
during  the  breeding-season,  which  disappears  during  the 

*  "  Comptes  Rendus."  Tom.  xlvi,  1858,  p.  353.  Tom.  xlvii,  1858, 
p.  916.  Tom.  liv,  1863,  p.  393.  The  noise  made  by  the  Umbrinas 
(Scicena  aquila),  is  said  by  some  authors  to  be  more  like  that  of  a 
flute  or  organ,  than  drumming:  Dr.  Zouteveen,  in  the  Dutch  trans- 
lation of  this  work  (vol.  ii,  p.  36),  gives  some  further  particulars  on 
the  sounds  made  by  fishes. 

f  The  Rev.  C.  Kingsley,  in  "  Nature,"  May,  1870,  p.  40. 

^Bell  "History  of  British  Reptiles,"  2nd  edit.  1849,  pp.  156-159. 


AMPHIBIANS. 


395 


winter.  Mr.  St.  George  Mivart  informs  me  that  it  is  not 
furnished  with  muscles,  and  therefore  cannot  be  used  for 
locomotion.  As  during  the  season  of  courtship  it  becomes 
edged  with  bright  colors,  there  can  hardly  be  a  doubt  that 
it  is  a  masculine  ornament.  In  many  species  the  body  pre- 
sents strongly  contrasted,  though  lurid  tints,  and  these 
become  more  vivid  during  the  breeding-season.  The  male, 
for  instance,  of  our  common  little  newt  ( Triton punctatus) 
is  "brownish-gray  above,  passing  into  yellow  beneath, 
which  in  the  spring  becomes  a  rich  bright  orange,  marked 
everywhere  with  round  dark  spots.''    The  edge  of  the  crest 


Rg.  32.    Triton  cristatus  (half  natural  size,  from  Bell's  "  British  Reptiles  ")■ 
Upper  figore,  male  daring  the  breeding-season;  lower  figore,  female. 

also  is  then  tipped  with  bright  red  or  violet.  The  female 
is  usually  of  a  yellowish-brown  color  with  scattered  brown 
dots,  and  the  lower  surface  is  often  quite  plain.*  The 
young  are  obscurely  tinted.  The  ova  are  fertilized  during 
the  act  of  deposition,  and  are  not  subsequently  tended  by 
either  parent.  We  may  therefore  conclude  that  the  males 
have  acquired  their  strongly-marked  colors  and  ornamental 
appendages  through  sexual  selection;  these  being  transmit- 
ted either  to  the  male  offspring  alone,  or  to  both  sexes. 

Anura  or  Batrachia. — With  many  frogs  and  toads  the 
colors  evidently  serve  as  a  protection,  such  as  the  bright 

»BeU,  "History  of  British  Reptiles,"  2d  edit.,  1849,  pp.  146,  151. 


396  THE  DESCENT  OF  MAN. 

green  tints  of  tree  frogs  and  the  obscure  mottled  shades  of 
many  terrestrial  species.  The  most  conspicuously-colored 
toad  which  lever  saw,  the  Phryniscus  nigricans,^  had  the 
whole  upper  surface  of  the  body  as  black  as  ink,  with  the 
soles  of  the  feet  and  parts  of  the  abdomen  spotted  with  the 
brightest  vermilion.  It  crawled  about  the  bare  sandy  or 
open  grassy  plains  of  La  Plata  under  a  scorching  sun,  and 
could  not  fail  to  catch  the  eye  of  every  passing  creature. 
These  colors  are  probably  beneficial  by  making  this  animal 
known  to  all  birds  of  prey  as  a  nauseous  mouthful. 

In  Nicaragua  there  is  a  little  frog  "  dressed  in  a  bright 
livery  of  red  and  blue  "  which  does  not  conceal  itself  like 
most  other  species,  but  hops  about  during  the  daytime,  and 
Mr.  Belt  saysf  that  as  soon  as  he  saw  its  happy  sense  of 
security  he  felt  sure  that  it  was  uneatable.  After  several 
trials  he  succeeded  in  tempting  a  young  duck  to  snatch  up 
a  young  one,  but  it  was  instantly  rejected;  and  the  duck 
'*  went  about  jerking  its  head  as  if  trying  to  throw  off  some 
unpleasant  taste." 

With  respect  to  sexual  differences  of  color  Dr.  Giinther 
does  not  know  of  any  striking  instance  either  with  frogs 
or  toads;  yet  he  can  often  distinguish  the  male  from  the 
female  by  the  tints  of  the  former  being  a  little  more  intense. 
Nor  does  he  know  of  any  striking  difference  in  external 
structure  between  the  sexes,  excepting  the  prominences  which 
become  developed  during  the  breeding-season  on  the  front 
legs  of  the  male,  by  which  he  is  enabled  to  hold  the  female.  X 
It  is  surprising  that  these  animals  have  not  acquired  more 
strongly-marked  sexual  characters;  for  though  cold-blooded 
their  passions  are  strong.  Dr.  Giinther  informs  me  that  he 
has  several  times  found  an  unfortunate  female  toad  dead 
and  smothered  from  having  been  so  closely  embraced  by 
three  or  four  males.  Frogs  have  been  observed  by  Prof. 
Hoffman  in  Giessen  fighting  all  day  long  during  the  breed- 
season,  and  with  so  much  violence  that  one  had  its  body 
ripped  open. 

*  "  Zoology  of  the  Vovage  of  the  '  Beagle,'  "  1843.  Bell,  ibid,  p. 
49. 

t  "  The  Naturalist  in  Nicaragua,"  1874,  p.  321. 

:}:  The  male  alone  of  tlie  Bufo  »ikimmensis  {\>t.  Anderson,  "  Proc. 
Zoolog.  Soc,"  1871,  p.  204)  has  two  plate  like  callosities  on  the 
thorax  and  certain  rugosities  on  the  fingers,  which  perhaps  subserve 
the  same  end  as  the  above  mentioned  prominences. 


REPTILES.  397 

Frogs  and  tords  offer  one  interesting  sexual  difference, 
namely,  in  the  musical  powers  possessed  by  the  males;  but 
to  speak  of  music,  when  applied  to  the  discordant  and 
overwhelming  sounds  emitted  by  male  bull-frogs  and  some 
other  species  seems,  according  to  our  taste,  a  singularly 
inappropriate  expression.  Nevertheless,  certain  frogs  sing 
in  a  decidedly  pleasing  manner.  Near  Rio  Janeiro  I  used 
often  to  sit  in  the  evening  to  listen  to  a  number  of  little 
Hylae  perched  on  blades  of  grass  close  to  the  water,  which 
sent  forth  sweet  chirping  notes  in  harmony.  The  various 
sounds  are  emitted  chiefly  by  the  males  during  the  breed- 
ing-season, as  in  the  case  of  the  croaking  of  our  common 
frog.  *  In  accordance  with  this  fact  the  vocal  organs  of  the 
males  are  more  highly  develo2)ed  than  those  of  the  females. 
In  some  genera  the  males  alone  are  provided  with  sacs 
which  open  into  the  larynx,  f  For  instance,  in  the  edible 
frog  (Rana  esculenta)  "the  sacs  are  peculiar  to  the  males, 
and  become,  when  filled  with  air  in  the  act  of  croaking, 
large  globular  bladders,  standing  out  one  on  each  side  of 
the  head  near  the  corners  of  the  mouth."  The  croak  of 
the  male  is  thus  rendered  exceedingly  powerful;  while  that 
of  the  female  is  only  a  slight  groaning  noise.  J  In  the  sev- 
eral genera  of  the  family  the  vocal  organs  differ  considerably 
in  structure,  and  their  development  in  all  cases  may  be 
attributed  to  sexual  selection. 

REPTILES. 

Chelonia. — Tortoises  and  turtles  do  not  off er  well-marked 
sexual  differences.  In  some  species  the  tail  of  the  male  is 
longer  than  that  of  the  female.  In  some  the  plastron  or 
lower  surface  of  the  shell  of  the  male  is  slightly  concave  in 
relation  to  the  back  of  the  female.  The  male  of  the  mud- 
turtle  of  the  United  States  ( Chrysemys  picta)  has  claws  on 
its  front  feet  twice  as  long  as  those  of  the  female;  and 
these  are  used  when  the  sexes  unite.  §  With  the  huge 
tortoise  of  the  Galapagos  Islands  ( Testudo  nigra)  the  males 

*Bell,  "History  of  British  Reptiles,"  1849,  p.  93. 

f  J.  Bishop,  in  "Todd's  Cyclop,  of  Anat.  and  Phys./'  vol.  iv,  p. 
1503. 

X  Bell,  ibid,  pp.  112-114. 

§Mr.  C.  J.  Maynard,  "The  American  Naturalist,"  Dec.  1869,  p. 
555. 


398  THE  DESCENT  OF  MAN, 

are  said  to  grow  to  a  larger  size  than  the  females.  During 
the  pairing  season,  and  at  no  other  time,  the  male  utters  a 
hoarse,  bellowing  noise  which  can  be  heard  at  the  distance 
of  more  than  a  hundred  yards;  the  female,  on  the  other 
hand,  never  uses  her  voice.* 

With  the  Testudo  elegans  of  India  it  is  said  '^  that  the 
combats  of  the  males  may  be  heard  at  some  distance  from 
the  noise  they  produce  in  butting  against  each  other,  ^'f 

Crocodilia. — The  sexes  apparently  do  not  diifer  in  color; 
nor  do  I  know  that  the  males  fight  together,  though  this 
is  probable,  for  some  kinds  make  a  prodigious  display 
before  the  females.  BartramJ;  describes  the  male  alligator 
as  striving  to  win  the  female  by  splashing  and  roaring  in 
the  midst  of  a  lagoon,  '^swollen  to  an  extent  ready  to 
burst,  with  its  head  and  tail  lifted  up,  he  springs  or  twirls 
round  on  the  surface  of  the  water  like  an  Indian  chief 
rehearsing  his  feats  of  war."  During  the  season  of  love  a 
musky  odor  is  emitted  by  the  submaxillary  glands  of  the 
crocodile  and  pervades  their  haunts.  § 

Ophidia. — Dr.  Giinther  informs  me  that  the  males  are 
always  smaller  than  the  females,  and  generally  have  longer 
and  slenderer  tails;  but  he  knows  of  no  other  difference  in 
external  structure.  In  regard  to  color,  he  can  almost 
always  distinguish  the  male  from  the  female  by  his  more 
strongly  pronounced  tints;  thus  the  black  zigzag  band  on 
the  back  of  the  male  English  viper  is  more  distinctly 
defined  than  in  the  female.  The  difference  is  much  plainer 
in  the  rattlesnakes  of  North  America,  the  male  of  which, 
as  the  keeper  in  the  Zoological  Gardens  showed  me,  can  at 
once  be  distinguished  from  the  female  by  having  more 
lurid  yellow  about  its  whole  •  body.  In  S.  Africa  the 
Bucephalus  capensis  presents  an  analogous  difference,  for 
the  female  ^^is  never  so  fully  variegated  with  yellow  on  the 
sides  as  the  male.  ||  The  male  of  the  Indian  Dipsas  cynodon, 

*  See  my   "  Journal  of  Researches  during    the  Voyage    of    the 
'Beagle,'"  1845,  p.  384. 
f  Dr.  GUnther,  *'  Reptiles  of  British  India,"  1864,  p.  7. 
X  "  Traveles  through  Carolina,"  etc.,  1791,  p.  128. 
§Owen,  "Anatomy  of  Vertebrates,"  vol.  i,  1866,  p.  615. 
II  Sir  Andrew  Smith,  "  Zoolog.  of  S.  Africa:  Reptilia,"  1849,  pi.  x. 


REPTILES.  399 

on  the  other  hand,  is  blackish-brown,  with  the  belly  partly 
black,  while  the  female  is  reddish  or  yellowish-olive,  with 
the  belly  either  uniform  yellowish  or  marbled  with  black. 
In  the  Tragops  dispar  of  the  same  country  the  male  is 
bright  green  and  the  female  bronze  colored.*  No  doubt 
the  colors  of  some  snakes  are  protective,  as  shown  by  the 
green  tints  of  tree-snakes  and  the  various  mottled  shades 
of  the  species  which  live  in  sandy  places;  but  it  is  doubtful 
whether  the  colors  of  many  kinds,  for  instance  of  the 
common  English  snake  a,nd  viper,  serve  to  conceal  them; 
and  this  is  still  more  doubtful  with  the  many  foreign 
species  which  are  colored  with  extreme  elegance.  The 
colors  of  certain  species  are  very  different  in  the  adult  and 
young  states.  \ 

During  the  breeding-season  the  anal  scent-glands  of 
snakes  are  in  active  function;  X  and  so  it  is  with  the  same 
glands  in  lizards,  and  as  we  have  seen  with  the  submaxillary 
glands  of  crocodiles.  As  the  males  of  most  animals  search 
for  the  females,  these  odoriferous  glands  probably  serve  to 
excite  or  charm  the  female,  rather  than  to  guide  her  to  the 
spot  where  the  male  may  be  found.  Male  snakes,  though 
appearing  so  sluggish,  are  amorous;  for  many  have  been 
observed  crowding  round  the  same  female,  and  even  round 
her  dead  body.  They  are  not  known  to  fight  together  from 
rivalry.  Their  intellectual  powers  are  higher  than  might 
have  been  anticipated.  In  the  Zoological  Gardens  they 
soon  learn  not  to  strike  at  the  iron  bar  with  which  their 
cages  are  cleaned;  and  Dr.  Keen,  of  Philadelphia,  informs 
me  that  some  snakes  which  he  kept  learned  after  four  or 
five  times  to  avoid  a  noose,  with  which  they  were  at  first 
easily  caught.  An  excellent  observer  in  Ceylon,  Mr.  E. 
Layard,§  saw  a  cobra  thrust  its  head  through  a  narrow  hole 
and  swallow  a  toad.  "^With  this  incumbrance  he  could 
not  withdraw  himself;  finding  this,  he  reluctantly  dis- 
gorged the  precious  morsel,  which  began  to  move  off;  this 

*Dr.  A.  Gunther,  "  Reptiles  of  British  India,"  Ray  Soc,  1864,  pp. 
304,  308. 

f  Dr.  Stoliczka,  "Journal  of  Asiatic  Soc.  of  Bengal,"  vol.  xxxix, 
1870,  pp.  205,  211. 

J  Owen,  "  Anatomy  of  Vertebrates,"  vol.  i,  1866,  p.  615. 

§  "  Rambles  in  Cevlon,"  in  '•  Annals  and  Ma^.  of  Nat.  Hist.,"  2d 
series,  vol.  ix,  1852,'  p.  333. 


400  THE  DESCENT  OF  MAN. 

was  too  much  for  snake  philosophy  to  bear,  and  the  toad 
was  again  seized,  and  again  was -the  snake,  after  violent 
efforts  to  escape,  compelled  to  part  with  its  prey.  This 
time,  however,  a  lesson  had  been  learned,  and  the  toad  was 
seized  by  one  leg,  withdrawn,  and  then  swallowed  in 
triumph." 

The  keeper  in  the  Zoological  Gardens  is  positive  that 
certain  snakes,  for  .instance  Orotalus  and  Python,  distin- 
guish him  from  all  other  persons.  Cobras  kept  together  in 
the  same  cage  apparently  feel  some  attachment  toward  each 
other.  * 

It  does  not,  however,  follow  because  snakes  have  some 
reasoning  power,  strong  passions  and  mutual  affection, 
that  they  should  likewise  be  endowed  with  sufficient  taste 
to  admire  brilliant  colors  in  their  partners,  so  as  to  lead  to 
the  adornment  of  the  species  through  sexual  selection. 
Nevertheless,  it  is  difficult  to  account  in  any  other  manner 
for  the  extreme  beauty  of  certain  species;  for  instance,  of 
the  coral-snakes  of  South  America,  which  are  of  a  rich  red 
with  black  and  yellow  transverse  bands.  I  well  remember 
how  much  surprise  I  felt  at  the  beauty  of  the  first  coral- 
snake  which  I  saw  gliding  across  a  path  in  Brazil.  Snakes 
colored  in  this  peculiar  manner,  as  Mr.  Wallace  states  on 
the  authority  of  Dr.  Giinther,f  are  found  nowhere  else  in 
the  world  except  in  South  America,  and  here  no  less  than 
four  genera  occur.  One  of  these,  Elaps,  is  venomous;  a 
second  and  widely-distinct  genus  is  doubtfully  venomous, 
and  the  two  others  are  quite  harmless.  The  species  belong- 
ing to  these  distinct  genera  inhabit  the  same  districts,  and 
are  so  like  each  other  that  no  one  "but  a  naturalist  would 
distinguish  tlie  harmless  from  the  poisonous  kinds."  Hence, 
as  Mr.  Wallace  believes,  the  innocuous  kinds  have  proba- 
bly acquired  their  colors  as  a  protection,  on  the  principle  of 
imitation;  for  they  would  naturally  be  thought  dangerous 
by  their  enemies.  The  cause,  however,  of  the  bright 
colors  of  the  venomous  Elaps  remain  to  be  explained,  and 
this  may  perhaps  be  sexual  selection. 

Snakes  produce  other  sounds  besides  hissing.  The 
deadly  Ecliis  carinata  has  on  its  sides  some  oblique  rows  of 
scales  of  a  peculiar  structure  with   serrated  edges ;  and 

*Dr.  Gunther,  "  Reptiles  of  British  India,"  1864,  p.  340. 
f  "Westminster  Review,"  July  1,  1867,  p.  3^. 


REPTILES.  401 

when  this  snake  is  excited  these  scales  are  rubbed  against 
each  other,  which  produces  '^a  curious  prolonged,  almost 
hissing  sound."  *  With  respect  to  the  rattling  of  the 
rattlesnake,  we  have  at  last  some  definite  information;  for 
Prof essor  Aughey  states,!  that  on  two  occassons,  being  him- 
self unseen,  he  watched  from  a  little  distance  a  rattlesnake 
coiled  up  with  head  erect,  which  continued  to  rattle  at 
short  intervals  for  half  an  hour;  and  at  last  he  saw  another 
snake  approach,  and  when  they  met  they  paired.  Hence 
he  is  satisfied  that  one  of  the  uses  of  the  rattle  is  to  bring 
the  sexes  together.  Unfortunately  he  did  not  ascertain 
whether  it  was  the  male  or  the  female  which  remained 
stationary  and  called  for  the  other.  But  it  by  no  means 
follows  from  the  above  fact  that  the  rattle  may  not  be  of 
use  to  these  snakes  in  other  ways,  as  a  warning  to  animals 
which  would  otherwise  attack  them.  Nor  can  I  quite  dis- 
believe the  several  accounts  which  have  appeared  of  their 
thus  paralyzing  their  prey  with  fear.  Some  other  snakes 
also  make  a  distinct  noise  by  rapidly  vibrating  their  tails 
against  the  surrounding  stalks  of  plants ;  and  I  have 
myself  heard  this  in  the  case  of  a  Trigonocephalus  in  South 
America. 

Lacertilia. — The  males  of  some,  probably  of  many  kinds 
of  lizards,  fight  together  from  rivalry.  Thus  the  arboreal 
Anolis  cristatelhcs  of  South  America  is  extremely  pugna- 
cious: "  During  the  spring  and  early  part  of  the  summer, 
two  adult  males  rarely  meet  without  a  contest.  On  first 
seeing  one  another,  they  nod  their  heads  up  and  down 
three  or  four  times,  and  at  the  same  time  expanding  the 
frill  or  pouch  beneath  the  throat;  their  eyes  glisten  with 
rage,  and  after  wa\ing  their  tails  from  side  to  side  for  a 
few  seconds,  as  if  to  gather  energy,  they  dart  at  each  other 
furiously,  rolling  over  and  over,  and  holding  firmly  with 
their  teeth.  The  conflict  generally  ends  in  one  of  the  com- 
batants losing  his  tail,  which  is  often  devoured  by  the 
victor.''  The  male  of  this  species  is  considerably  larger 
than  the  female; J  and  this,  as  far  as  Dr.  Giinther  has  been 

*Dr.  Anderson,  "Proc.  Zoolog.  Soc,"  1871,  p.  196. 
■f  "  The  American  Naturalist,"  1873,  p.  85. 

^Mr.  N.  L.  Austen  kept  these  animals  alive  for  a  considerable 
Jame^  see  "Land  ^nd  Water,"  Jul^,  1867,  p.  9. 


402  THE  DESCENT  OF  MAN. 

able  to  ascertain,  is  the  general  rule  with  lizards  of  all  kinds. 
The  male  alone  of  the  Cyrtodactylus  rubidus  of  the  Anda- 
man Islands  possesses  pre-anal  pores;  and  these  pores,  judg- 
ing from  analogy,  probably  serve  to  emit  an  odor.* 

The  sexes  often  differ  greatly  in  various  external  charac- 
ters. The  male  of  the  above-mentioned  Anolis  is  furnished 
with  a  crest  which  runs  along  the  back  and  tail,  and 
can  be  erected  at  pleasure ;  but  of  this  crest  the 
female  does  not  exhibit  a  trace.  In  the  Indian 
Cophotis  ceylanica  the  female  has  a  dorsel  crest,  though 
much  less  developed  than  in  the  male;  and  so  it  is,  as  Dr. 

Giinther  informs  me,  with  the 
females     of     many     Iguanas, 
Chameleons  and  other  lizards. 
In    some   species,   however, 
the  crest  is  equally  developed 
in  both  sexes,  as  in  the  Iguana 
tuberculata.       In    the    genus 
Sitana,    the    males   alone  are 
furnished  with  a  large  throat- 
pouch  (fig.  33),  which  can  be 
folded  up   like  a  fan,  and  is 
Fi^.  33.   Sitana  minor.    Male  with  colored  blue,  black   and   red; 
Sr„SsKRl%&rn,r«J-lr  tut  these  splendid  colors  are 

exhibited  only  during  the  pair- 
ing-season. The  female  does  not  possess  even  a  rudi- 
ment of  this  appendage.  In  the  Anolis  cristatellns  accord- 
ing to  Mr.  Austen,  the  throat  pouch,  which  is  bright  red 
marbled  with  yellow,  is  present  in  the  female,  though  in  a 
rudimental  condition.  Again,  in  certain  other  lizards, 
both  sexes  are  equally  well  provided  with  throat  pouches. 
Here  we  see  with  species  belonging  to  the  same  group,  as 
in  so  many  previous  cases,  the  same  character  either  con- 
fined to  the  males  or  more  largely  developed  in  them  than 
in  the  females,  or  again  equally  developed  in  both  sexes. 
The  little  lizards  of  the  genus  Draco,  which  glide  through 
the  air  on  their  rib-supported  parachutes,  and  which  in  the 
beauty  of  their  colors  baffle  description,  are  furnished  with 
skinny  appendages  to  the  throat  "  like  the  wattles  of  gall- 
inaceous birds.  ^'     These  become  erected  when  the  animal 

*  Stoliczka,  "Journal  of  Asiatic  Soc.  of  Bengal,"  vol.  xxxiv,  1^70, 
p.  166. 


REPTILES.  403 

is  excited.  They  occur  in  both  sexes,  but  are  best  devel- 
oped when  the  male  arrives  at  maturity,  at  which  age  the 
middle  appendage  is  sometimes  twice  as  long  as  the  head. 
Most  of  the  species  likewise  have  a  low  crest  running  along 
the  neck;  ana  this  is  much  more  developed  in  the  full-grown 
males  than  in  the  females  or  young  males.* 

A  Chinese  species  is  said  to  live  in  pairs  during  the 
spring;  "  and  if  one  is  caught  the  other  falls  from  the  tree 
to  the  ground,  and  allows  itself  to  be  captured  with  im- 
punity,   I  presume  from  despair,  f 

There  are  other  and  much  more 
remarkable  differences  between 
the  sexes  of  certain  lizards.  The 
male  of  Ceratophora  aspera  bears 
on  the  extremity  of  his  snout  an 
appendage  half  as  long  as  the  head. 
It  is  cylindrical,  covered  with 
scales,  flexible  and  apparently 
capable  of  erection;  in  the  female 
it  is  quite  rudimental.  In  a  second 
species  of  the  same  genus  a  ter- 
minal scale  forms  a  minute  horn 
on  the  summit  of  the  flexible 
appendage;  and  in  a  third  species  «    „,  ^     ^    ^      „,  ^^    ,.. 

A^c^,  J  J  ±--  la  rtii\  i.1  ^1  1  Fiff.  34.  Ceratophora  Stoddartn. 
G.  btoaaartll  (tig.  o4),  the   whole      upper    figure,   male;    lower 

appendage  is  converted  into  a  horn,     fi^re,  female, 
which  is  usually  of  a  white  color, 

but  assumes  a  purplish  tint  when  the  animal  is  excited.  In 
the  adult  male  of  this  latter  species  the  horn  is  half  an  inch 
in  length,  but  it  is  of  quite  minute  size  in  the  female  and  in 
the  young.  These  appendages,  as  Dr.  Giinther  has 
remarked  to  me,  may  be  compared  with  the  combs  of  gall- 
inaceous birds,  and  apparently  serve  as  ornaments. 

In  the  genus  Chameleon  we  come  to  the  acme  of  differ- 
ence between  the  sexes.  The  upper  part  of  the  skull  of  the 
male  C.  hifurcus  (fig.  35),  an  inhabitant  of  Madagascar,  is 
produced  into  two  great,  solid,  bony  projections,  covered 

*  All  the  foregoing  statements  and  quotations  in  regard  to  Copho- 
tis,  Sitana  and  Draco,  as  well  as  the  following  facts  in  regard  to 
Ceratophora  and  Chamaeleon,  are  from  Dr.  Giinther  himself,  or  from 
his  magnificent  work  on  the  "  Reptiles  of  British  India,"  Ray  See., 
1864,  pp.  122,  130,  135. 

f  Mr.  Swmhoe,  "Proc.  Zoolog.  Soc.,"  1870,  p.  240. 


404 


THE  DESCENT  OF  MAN. 


with  scales  like  tne  rest  of  the  head;  and  of  tliis  wonderful 
modification  of  structure  the  female  exhibits  only  a  rudi- 
ment. Again,  in  Cliamcdeo  Oivenii  (fig.  3(5),  from  the 
west  coast  of  Africa,  the  male  bears  on  his  snout  and  fore- 


Pig.  35.    Chamaeleo  bifurcus.    Upper  figure,  male ;  lower  figure,  female. 


head  three  curious  horns,  of  which  the  female  has  not  a 
trace.  These  horns  consist  of  an  excrescence  of  bone 
covered  with  a  smooth  sheath,  forming  part  of  the  general 
integuments  of  the  body,  so  that  they  are  identical  in 
structure  with  those  of  a  bull,  goat,  or  other  sheath-horned 
ruminant.  Although  the  three  horns  differ  so  much  in 
appearance  from  the  two  great  prolongations  of  the  skull 


HEPTtLBS. 


405 


in  C.  Mfurcus,  we  can  hardly  doubt  that  they  serve  the 
same  general  purpose  in  the  economy  of  these  two  animals. 
The  first  conjecture,  which  will  occur  to  every  one,  is  that 
they  are  used  by  the  males  for  fighting  together;  and  as 
these  animals  are  very  quarrelsome,*  this  is  probably  a  cor- 
rect view.  Mr.  T.  W.  Wood  also  informs  me  that  he  once 
watched  two  individuals  of  C.  pumilus  fighting  violently 
on  the  branch  of  a  tree;  they  flung  their  heads  about  and 
tried  to  bite  each  other;  they  then  rested  for  a  time  and 
afterward  continued  their  battle. 


Fig.  36.    Chamaeleo  Owenii.    Upper  figure,  male;  lower  figure,  female. 


With  many  lizards  the  sexes  differ  slightly  in  color,  the 
tints  and  stripes  of  the  males  being  brighter  and  more  dis- 
tinctly defined  than  in  the  females.  This,  for  instance,  is 
the  case  with  the  above  Cophotis  and  with  the  Acmitho- 
dadylus  capensis  of  S.  Africa.  In  a  Cordylus  of  the  latter 
country,  the  male  is  either  much  redder  or  greener  than 
the  female.  In  the  Indian  Calotes  nigrilalris  there  is  a 
still  greater  difference;  the  lips  also  of  the  male  are  black, 
while  those  of  the  female  are  green.  In  our  common  little 
viviparous  lizard  {Zootoca  vivipara)  "  the  under  side  of  the 
body  and  base  of  the  tail  in  the  male  are  bright  orange. 


78. 


Dr.  Bucliolz,  "  Monatsbericht  K.  Preuss.  Akad.,"  Jan.,  1874,  p. 


406  THE  DESCENT  OF  MAN, 

spotted  with  black;  in  the  female  these  parts  are  pale  gray- 
ish green  without  spots."*  AVe  have  seen  that  the  males 
alone  of  Sitana  possess  a  throat-pouch;  and  this  is  splen- 
didly tinted  with  blue,  black  and  red.  In  the  Prodotretus 
tenuis  of  Chili  the  male  alone  is  marked  with  spots  of  blue, 
green  and  coppery  red.f  In  many  cases  the  males  retain 
the  same  colors  throughout  the  year,  but  in  others  they 
become  much  brighter  during  the  breeding-season;  I  may 
give  as  an  additional  instance  the  Calotes  maria,  which  at 
this  season  has  a  bright  red  head,  the  rest  of  the  body  being 
green.  I 

Both  sexes  of  many  species  are  beautifully  colored  exactly 
alike;  and  there  is  no  reason  to  suppose  that  such  colors  are 
protective.  No  doubt  with  the  briglit-green  kinds  which 
live  in  the  midst  of  vegetation,  tins  color  serves  to  conceal 
them;  and  in  N.  Patagonia  I  saw  a  lizard  [Prodotretus 
multimaculatus)  which,  when  frightened,  flattened  its  body, 
closed  its  eyes,  and  then  from  its  mottled  tints  was  hardly 
distinguishable  from  the  surrounding  sand.  But  the  bright 
colors  with  which  so  many  lizards  are  ornamented,  as  well 
as  their  various  curious  appendages,  were  probably  acquired 
by  the  males  as  an  attraction,  and  then  transmitted  either 
to  their  male  offspring  alone,  or  to  both  sexes.  Sexual 
selection,  indeed,  seems  to  have  played  almost  as  important 
a  part  with  reptiles  as  with  birds;  and  the  less  conspicuous 
colors  of  the  females  in  comparison  with  the  males  cannot 
be  accounted  for,  as  Mr.  Wallace  believes  to  be  tlie  case 
with  birds,  by  the  greater  exposure  of  the  females  to  danger 
during  incubation. 

*Bell,  "History  of  British  Reptiles,"  2d  edit.,  1849.  p.  40. 

fFor  Proctotretus  see  "Zoology  of  the  Voyage  of  the  'Beagle;' 
Reptiles,"  by  Mr.  Bell,  p.  8.  For  the  lizards  of  S.  Africa,  see 
"Zoology  of  S.  Africa:  Reptiles,"  by  Sir  Andrew  Smith,  pi.  25  and 
39.  For  the  Indian  Calotes,  see  "  Reptiles  of  British  India,"  by  Dr. 
G  anther,  p.  143. 

I  Qiinther  in  "Proc.  Zoolog.  Soc,"  1870,  p.  778,  with  a  colored 
figure. 


BIRDS.  407 


CHAPTER  Xm. 

SECOifDARY  SEXUAL   CHARACTEBS  OF   BIRDS. 

Sexual  differences — Law  of  battle — Special  weapons — Vocal  organs 
— Instrumental  music  —  Love-antics  and  dances  —  Decorations, 
permanent  and  seasonal — Double  and  single  annual  moults — 
Display  of  ornaments  by  the  males. 

Secondary  sexual  characters  are  more  diversified  and 
conspicuous  in  birds,  though  not  perhaps  entailing  more 
important  changes  of  structure,  than  in  any  other  class  of 
animals.  I  shall,  therefore,  treat  the  subject  at  consider- 
able length.  Male  birds  sometimes,  though  rarely,  possess 
special  weapons  for  fighting  with  each  other.  They  charm  the 
female  by  vocal  or  instrumental  music  of  the  most  varied 
kinds.  They  are  ornamented  by  all  sorts  of  combs,  wattles, 
protuberances,  horns,  air-distended  sacks,  top-knots,  naked 
shafts,  plumes  and  lengthened  feathers  gracefully  spring- 
ing from  all  parts  of  the  body.  The  beak  and  naked  skin 
about  the  head  and  the  feathers  are  often  gorgeously  col- 
ored. The  males  sometimes  pay  their  court  by  dancing  or 
by  fantastic  antics  performed  either  on  the  ground  or  in 
the  air.  In  one  instance,  at  least,  the  male  emits  a  musky 
odor,  which  we  may  suppose  serves  to  charm  or  excite  the 
female;  for  that  excellent  observer,  Mr.  Ramsay,*  says  of 
the  Australian  musk  duck  {Biziura  lohata)  that  ''  the 
smell  which  the  male  emits  during  the  summer  months  is 
confined  to  that  sex,  and  in  some  individuals  is  retained 
throughout  the  year.  I  have  never,  even  in  the  breeding- 
season,  shot  a  female  which  had  any  smell  of  musk."  So 
powerful  is  this  odor  during  the  pairing-season  that  it  can 
be  detected  long  before  the  bird  can  be  seen.f  On  the 
whole,  birds  appear  to  be  the  most  aesthetic  of  all  animals, 
excepting  of  course  man,  and  they  have  nearly  tlie  same 

*  "  Ibis,'*  vol.  iii  (new  series),  1867,  p.  414. 

f  Gould,  *' Hand-book  to  the  Birds  of  Australia,"  1865,  vol.  ii,  p. 
383. 


408  THE  DESCENT  OF  MAN. 

taste  for  the  beautiful  as  we  have.  This  is  shown  by  our 
enjoyment  of  the  singing  of  birds,  and  by  our  women,  both 
civilized  and  savage,  decking  their  heads  with  borrowed 
plumes  and  using  gems  which  are  hardly  more  brilliantly 
colored  than  the  naked  skin  and  wattles  of  certain  birds. 
In  man,  however,  when  cultivated  the  sense  of  beauty  is 
manifestly  a  far  more  complex  feeling  and  is  associated 
with  various  intellectual  ideas. 

Before  treating  of  the  sexual  characters  with  which  we 
are  here  more  particularly  concerned,  I  may  just  allude  to 
certain  differences  between  the  sexes  which  apparently 
depend  on  differences  in  their  habits  of  life;  for  such 
cases,  though  common  in  the  lower,  are  rare  in  the  higher 
classes.  Two  humming  -  birds  belonging  to  the  genus 
Eustephanus,  which  inhabit  the  Island  of  Juan  Fernandez, 
were  long  thought  to  be  specifically  distinct,  but  are 
now  known,  as  Mr.  Gould  informs  me,  to  be  the  male 
and  female  of  the  same  species,  and  they  differ  slightly 
in  the  form  of  the  beak.  In  another  genus  of  hum- 
ming-birds ( Grypus)  the  beak  of  the  male  is  serrated  along 
the  margin  and  hooked  at  the  extremity,  thus  differing 
much  from  that  of  the  female.  In  the  Neomorpha  of  New 
Zealand,  there  is,  as  we  have  seen,  a  still  wider  difference 
in  the  form  of  the  beak  in  relation  to  the  manner  of  feed- 
ing of  the  two  sexes.  Something  of  the  same  kind  has 
been  observed  with  the  go\di^\\ch.  {Car duelis  elegans),  for  I 
am  assured  by  Mr.  Jenner  Weir  that  the  bird-catchers 
can  distinguish  the  males  by  their  slightly  longer  beaks. 
The  flocks  of  males  are  often  found  feeding  on  the  seeds  of 
the  teazle  (Dipsacus),  which  they  can  reach  with  their 
elongated  beaks,  while  the  females  more  commonly  feed  on 
the  seeds  of  the  betony  or  Scrophularia.  With  a  slight 
difference  of  this  kind  as  a  foundation  we  can  see  how  the 
beaks  of  the  two  sexes  might  be  made  to  differ  greatly 
through  natural  selection.  In  some  of  the  above  cases, 
however,  it  is  possible  that  the  beaks  of  the  males  may 
have  been  first  modified  in  relation  to  their  contests  with 
other  males;  and  that  this  afterward  led  to  slightly  changed 
habits  of  life. 

Law  of  Battle. — Almost  all  male  birds  are  extremely 
pugnacious,  using  their  beaks,  wings,  and  legs  for  fighting 
together.     We  see  this  every  spring  with  our  robins  and 


BIRDS.  409 

span'ows.  Tlie  smallest  of  all  birds,  namely,  the  humming- 
bird, is  one  of  the  most  quarrelsome.  Mr.  Gosse*  describes 
a  battle  in  which  a  pair  seized  hold  of  each  other's  beaks, 
and  whirled  round  and  round  till  they  almost  fell  to  the 
ground;  and  M.  Montes  de  Oca,  in  speaking  of  another 
genus  of  humming-bird,  says  that  two  males  rarely  meet 
without  a  fierce  aerial  encounter;  when  kept  in  cages  '^  their 
fighting  has  mostly  ended  in  the  splitting  of  the  tongue  of 
one  of  the  two,  which  then  surely  dies  from  being  unable 
to  feed.^'t  With  Waders,  the  males  of  the  common  Avater- 
hen  (Gall miila  chloropus)  ''when  pairing,  fight  violently 
for  the  females;  they  stand  nearly  upright  in  the  water  and 
strike  with  their  feet."  Two  were  seen  to  be  thus  engaged 
for  half  an  hour,  until  one  got  hold  of  the  head  of  the 
other,  which  would  have  been  killed  had  not  the  observer 
interfered;  the  female  all  the  time  looking  on  as  a  quiet 
spectator.  J;  Mr.  Blyth  informs  me  that  the  males  of  an 
allied  bird  { (rallicrex  cr (status)  are  a  third  larger  than  the 
females,  and  are  so  pugnacious  during  the  breeding-season 
that  they  are  kept  by  the  natives  of  Eastern  Bengal  for  the 
sake  of  fighting.  Various  other  birds  are  kept  in  India  for 
the  same  purpose,  for  instance,  the  bulbuls  (Pycnonotus 
h(B7)iorrhous)  which  "fight  with  great  spirit."  § 

The  polygamous  rutf.  Machetes  pugnax  (fig.  37),  is 
notorious  for  his  extreme  pugnacity;  and  in  the  spring,  the 
males,  which  are  considerably  larger  than  the  females,  con- 
gregate day  after  day  at  a  particular  spot,  where  the  females 
propose  to  lay  their  eggs.  The  fowlers  discover  these  spots 
by  the  turf  being  trampled  somewhat  bare.  Here  they  fight 
very  much  like  game-cocks,  seizing  each  other  with  their 
beaks  and  striking  with  their  wings.  The  great  ruff  of 
feathers  round  the  neck  is  then  erected,  and  according  to 
Col.  Montagu  "^  sweeps  the  ground  as  a  shield  to  defend 
the  more  tender  parts;"  and  this  is  the  only  instance  known 
to  me  in  the  case  of  birds  of  any  structure  serving  as  a 
shield.     The  ruff  of  feathers,  however,  from  its  varied  and 

♦Quoted  by  Mr.  Gould,  "Introduction  to  the  TrocMlidae,"  1861, 
p.  29. 

t  Gould,  ibid,  p.  52. 

JW.  Thompson,  "Nat.  Hist,  of  Ireland;  Birds,"  vol.  ii,  1850,  p. 
327. 

§  Jerdon,  "Birds  of  India,"  1863,  vol.  ii,  p.  SC. 


410 


THE  DESCENT  OF  MAN. 


rich  colors  probably  serves  in  chief  part  as  an  ornament* 
Like  most  pugnacious  birds,  they  seem  always  ready  to 


fight,  and  when  closely  confined  often  kill  each  other;  but 
Montagu  observed  that  their  pugnacity  becomes  greater 
during  the  spring,  when  the  long  feathers  on  their  necks 
are  fully  developed;  and  at  this  period  the  least  movement 


BIBDB.  411 

by  any  one  bird  provokes  a  general  battle.  *  Of  the  pug- 
nacity of  web-footed  birds,  two  instances  will  suffice;  in 
Guiana  "  bloody  fights  occur  during  the  breeding-season 
between  the  males  of  the  wild  musk-duck  {Cairinamo- 
schata);  and  where  these  fights  have  occurred  the  "  river  is 
covered  for  some  distance  with  feathers."  f  Birds  which 
seem  ill-adapted  for  fighting  engage  in  fierce  conflicts;  thus 
the  stronger  males  of  the  pelican  drive  away  the  weaker 
ones,  snapping  with  their  huge  beaks  and  giving  heavy 
blows  with  their  wings.  Male  snipe  fight  together,  "  tug- 
ging and  pushing  each  other  with  their  bills  in  the  most 
curious  manner  ima^nable."  Some  few  birds  are  believed 
never  to  fight;  this  is  the  case,  according  to  Audubon,  with 
one  of  the  woodpeckers  of  the  United  States  (Picu  sau- 
ratus),  although  *'the  hens  are  followed  by  even  half  a 
dozen  of  their  gay  suitors."  % 

The  males  of  many  birds  are  larger  than  the  females, 
and  this  no  doubt  is  the  result  of  the  advantage  gained  by 
the  larger  and  stronger  males  over  their  rivals  during  many 
generations.  The  difference  in  size  between  the  two  sexes 
is  carried  to  an  extreme  point  in  several  Australian  species; 
thus  the  male  musk-duck  (Biziura)  and  the  male  Cinclor- 
amphtis  cruralis  (allied  to  our  pipits)  are  by  measure- 
ment actually  twice  as  large  as  their  respective  females.  § 
With  many  other  birds  the  females  are  larger  than  the 
males;  and,  as  formerly  remarked,  the  explanation  often 
given,  namely,  that  the  females  have  most  of  the  work  in 
feeding  their  young,  will  not  suffice.  In  some  few  cases, 
as  we  shall  hereafter  see,  the  females  apparently  have 
acquired  their  greater  size  and  strength  for  the  sake  of  con- 
quering other  females  and  obtaining  possession  of  the 
males. 

The  males  of  many  gallinaceous  birds,  especially  of  the 
polygamous  kinds,  are  furnished  with  special  weapons  for 
fighting  with  their  rivals,  namely  spurs,  which  can  be  used 

*  Macgillivray,  *'Hist.  Brit.  Birds,"  vol.  iv,  1852,  pp.  177-181. 

f  Sir  R.  Schomburgk,  in  "  Journal  of  R.  Qeograph.  Soc.,"  vol.  xiii, 
1843,  p.  31. 

•  J "  Ornithological  Biography,"  vol.  i,  p.  191.  For  pelicans  and 
snipes,  see  vol.  iii,  pp  138,  477. 

§  Gould,  "  Hand-book  of  Birds  of  Australia,**  voL  i,  p.  395;  vol.  ii, 
p.  383. 


412  THE  DESCENT  OF  MAN. 

with  fearful  effect.  It  has  been  recorded  by  a  trustworthy 
A^riter*  that  in  Derbyshire  a  kite  struck  at  a  game-hen 
accompanied  by  her  chickens,  when  the  cock  rushed  to  the 
rescue,  and  drove  his  spur  right  through  the  eye  and  skull 
of  the  aggressor.  The  spur  was  with  difficulty  drawn  from 
the  skull,  and  as  the  kite,  though  dead,  retained  his  grasp, 
the  two  birds  were  firmly  locked  together ;  but  the  cock 
when  disentangled  was  very  little  injured.  The  invincible 
courage  of  the  game-cock  is  notorious ;  a  gentleman  who 
long  ago  witnessed  the  brutal  scene,  told  me  that  a  bird 
had  both  its  legs  broken  by  some  accident  in  the  cock-pit, 
and  the  owner  laid  a  wager  that  if  the  legs  could  be  spliced 
so  that  the  bird  could  stand  upright,  he  would  continue 
fighting.  This  was  effected  on  the  spot,  and  the  bird 
fought  with  undaunted  courage  until  he  received  his  death- 
stroke.  In  Ceylon  a  closely  allied,  wild  species,  the  Gallus 
Stanletji,  is  known  to  fight  desperately  ''  in  defense  of  his 
seraglio,^'  so  that  one  of  the  combatants  is  frequently  found 
dead.f  An  Indian  partridge  {Ortygoruis  giilaris),  the 
male  of  which  is  furnished  with  strong  and  sharp  spurs,  is 
so  quarrelsome  ' '  that  the  scars  of  former  fights  disfigure 
the  breast  of  almost  every  bird  you  kill.  "J 

The  males  of  almost  all  gallinaceous  birds,  even  those 
which  are  not  furnished  with  spurs,  engage  during  the 
breeding-season  in  fierce  conflicts.  The  Capercailzie  and 
Black-cock  (Tetrao  iii^ogallus  and  T.  tetrix)  which  are 
both  polygamists,  have  regular  appointed  places,  where 
during  many  weeks  they  congregate  in  numbers  to  fight 
together  and  to  display  their  charms  before  the  females. 
Dr.  W.  Kovalevsky  informs  me  that  in  Russia  he  has  seen 
the  snow  all  bloody  on  the  arenas  where  the  capercailzie 
have  fought;  and  the  black-cocks  *'  make  the  feathers  fly 
in  every  direction,"  when  several  ^'  engage  in  a  battle 
royal."  The  elder  Brehm  gives  a  curious  account  of  the 
Balz,  as  the  love-dances  and  love-songs  of  the  black-cock 
are  called  in  Germany.  The  bird  utters  almost  contin- 
uously the  strangest  noises:  ^Mie  holds  his  tail  up  and 
spreads  it  out  like  a  fan,  he  lifts  up  his  head  and  neck  with 
all  the  feathers  erect,  and  stretches  his  wings  from  the, 

*Mr.  Hewitt  in  the  "Poultry  Book  by  Tegetineier,"  1866,  p.  137. 
f  Layard,  "  Annals  and  Mag.  of  Nat.  Hist.,"  vol.  xiv,  1854,  p.  63, 
^  Jerdon,  "Birds  of  India,"  vol.  iii,  p.  574. 


BIRDS.  413 

body.  Then  he  takes  a  few  jumps  in  different  direc- 
tions, sometimes  in  a  circle,  and  presses  the  under  part 
of  his  beak  so  hard  against  the  ground  that  the 
chin  feathers  are  rubbed  off.  During  these  move- 
ments he  beats  his  wings  and  turns  round  and 
round.  The  more  ardent  he  grows  the  more  lively  he 
becomes,  until  at  last  the  bird  appears  like  a  frantic  creat- 
ure." At  such  times  the  black-cocks  are  so  absorbed  that 
they  become  almost  blind  and  deaf,  but  less  so  than  the 
capercailzie;  hence  bird  after  bird  may  be  shot  on  the  same 
spot,  or  even  caught  by  the  hand.  After  performing  these 
antics  the  males  begin  to  fight;  and  the  same  black-cock, 
in  order  to  prove  his  strength  over  several  antagonists,  will 
visit  in  the  course  of  one  morning  several  Balz-places,  which 
remain  the  same  during  successive  years.* 

The  peacock  with  his  long  train  appears  more  like  a 
dandy  than  a  warrior,  but  he  sometimes  engages  in  fierce 
contests;  the  Rev.  W.  Darwin  Fox  informs  me  that  at  some 
little  distance  from  Chester  two  peacocks  became  so  excited 
while  fighting  that  they  flew  over  the  whole  city,  still 
engaged,  until  they  alighted  on  the  top  of  St.  John's  tower. 

The  spur,  in  those  gallinaceous  birds  which  are  thus  pro- 
vided, is  generally  single;  but  Polyplectron  (see  fig.  51) 
has  two  or  more  on  each  leg;  and  one  of  the  blood-pheas- 
ants (Ithaginis  ci'uentus)  has  been  seen  with  five  spurs. 
The  spurs  are  generally  confined  to  the  male,  being  repre- 
sented by  mere  knobs  or  rudiments  in  the  female;  but  the 
females  of  the  Java  peacock  (Favo  muticus)  and,  as  I  am 
informed  by  Mr.  Blyth,  of  the  small  fire-backed  pheasant 
{Euplocamus  erytliroptlialmus)  possess  spurs.  In  Galloper- 
dix  it  is  usual  for  the  males  to  have  two  spurs,  and  for  the 
females  to  have  only  one  on  each  leg.f  Hence  spurs  may 
be  considered  as  a  masculine  structure,  which  has  been 
occasionally  more  or  less  transferred  to  the  females.  Like 
most  other  secondary  sexual  characters,  the  spurs  are  highly 
variable,  both  in  number  and  development,  in  the  same 
species. 

Various  birds  have  spurs  on  their  wings.     But  the  Egyp- 

*Brehm,  "  Illust.  Thierleben,"  1867,  B.  iv,  s.  351.  Some  of  the 
foregoing  statements  are  taken  from  L.  Lloyd,  "The  Game  Birds  of 
Sweden,"  etc.,  1867,  p.  79. 

f  Jerdon,  "  Birds  of  India,"  on  Ithaginis,  vol.  iii,  p.  523;  on  Gallo- 
perdix,  p.  541. 


414  THE  DESCENT  OF  MAN. 

tiau  goose  {Chenalopex  mgyptiacus)  has  only  "bare  obtuse 
knobs/'  and  these  probably  show  us  the  first  steps  by  which 
true  spurs  have  been  developed  in  other  species.  In  the 
spur- winged  goose  (Plectropterus  gambensis)  the  males 
have  much  larger  spurs  than  the  females;  and  they  use 
them,  as  I  am  informed  by  Mr.  Bartlett,  in  fighting  to- 
gether, so  that,  in  this  case,  the  wing-spurs  serve  as  sexual 
weapons ;  but  according  to  Livingstone,  they  are  chiefiy 
used  in  the  defense  of  the  young.  The  Palamedea  (fig.  38) 
is  armed  with  a  pair  of  spurs  on  each  wing;  and  these  are 
such  formidable  weapons  that  a  single  blow  has  been  known 
to  drive  a  dog  howling  away.  But  it  does  not  appear  that 
the  spurs  in  this  case,  or  in  that  of  some  of  the  spur- 
winged  rails,  are  larger  in  the  male  than  in  the  female.* 
In  certain  plovers,  however,  the  wing-spurs  must  be  con- 
sidered as  a  sexual  character.  Thus  in  the  male  of  our 
common  peewit  ( Variellus  cristatus)  the  tubercle  on  tlie 
shoulder  of  the  wing  becomes  more  prominent  during  the 
breeding-season,  and  the  males  fight  together.  In  some 
species  of  Lobivanellus  a  similar  tubercle  becomes  developed 
during  the  breeding-season  '^  into  a  short,  horny  spur.'"  In 
the  Australian  L.  lobatus  both  sexes  have  spurs,  but  these 
are  much  larger  in  the  males  than  in  the  females.  In  an 
allied  bird,  the  Hoplopterus  armatus,  the  spurs  do  not  in- 
crease in  size  during  the  breeding-season;  but  these  birds 
have  been  seen  in  Egypt  to  fi^ht  together,  in  the  same  man- 
ner as  our  peewits,  by  turning  suddenly  in  the  air  and 
striking  sideways  at  each  other,  sometimes  with  fatal  results. 
Thus  also  they  drive  away  other  enemies,  f 

The  season  of  love  is  that  of  battle;  but  the  males  of 
some  birds,  as  of  the  game-fowl  and  ruff,  and  even  the 
young  males  of  the  wild  turkey  and  grousej  are  ready  to 

*For  the  Egyptian  goose,  see  Macgillivray,  "  British  Birds,"  vol. 
iv,  p.  639.  For  Plectropterus,  "Livingstone's  Travels,"  p.  254 
For  Palamedea,  Brehm's  "  Thierleben,"  B.  iv,  s.  740.  See  also  on 
this  bird  Azara,  "Voyages  dans  TAmerique  merid.,"  torn,  iv,  1809, 
pp.  179,  253. 

f  See,  on  our  peewit,  Mr.  R.  Carr  in  "Land  and  Water,"  Aug,  8, 
1868,  p.  46.  In  regard  to  Lobivanellus,  see  Jerdon's  "Birds  of 
India,"  vol.  iil  p.  647,  and  Gould's  "Hand-book  of  Birds  of  Austra 
lia,"  vol.  ii,  p.  220.  For  the  Holopterus.  see  Mr.  Allen  in  the 
"Ibis,'  vol.  V,  1863.  p.  156. 

|Au4uboji,  "Ornith.  Biography,"  vol.  ii,  p.  49^;  vol.  i,  pp.  4-13. 


BIRDS.  416 

fight  whenever  they  meet.     Tlie   presence  of  the  female  is 


Fig.  38.    Palamedea  cornuta  (from  Brehm  i.  showing  the  double  wing-spurs  and 
the  filament  on  the  head. 

the  teferrima  helli  causa.     The  Bengali  baboos  make  the 
pretty  little  m^les  of  the  amadavat  {Estrelda  amandava) 


41G  THE  DESCENT  OF  MAN, 

fight  together  by  placing  three  small  cages  in  a  row  with  a 
female  in  the  middle-;  after  a  little  time  the  two  males  are 
turned  loose  and  immediately  a  desperate  battle  ensues.* 
When  many  males  congregate  at  the  same  appointed  spot 
and  fight  together,  as  in  the  case  of  grouse  and  various 
other  birds,  they  are  generally  attended  by  the  females,! 
which  afterward  pair  with  the  victorious  combatants.  But 
in  some  cases  the  pairing  precedes  instead  of  succeeding 
the  combat;  thus  according  to  Audubon,  |  several  males  of 
the  Virginian  goat -sucker  {Caprimulgus  virgmianus) 
'^  court  in  a  highly  entertaining  manner  the  female,  and 
no  sooner  has  she  made  her  choice  than  her  approved  gives 
chase  to  all  intruders,  and  drives  them  beyond  his 
dominions.'''  Generally  the  males  try  to  drive  away  or  kill 
their  rivals  before  they  pair.  It  does  not,  however,  appear 
that  the  females  invariably  prefer  the  victorious  males.  I 
have  indeed  been  assured  by  Dr.  W.  Kovalevsky  that  the 
female  capercailzie  sometimes  steals  away  with  a  young 
male  who  has  not  dared  to  enter  the  arena  with  the  older 
cocks,  in  the  same  manner  as  occasionally  happens  with  the 
does  of  the  red-deer  in  Scotland.  When  two  males  contend 
in  presence  of  a  single  female,  the  victor^  no  doubt,  com- 
monly gains  his  desire;  but  some  of  these  battles  are  caused 
by  wandering  males  trying  to  distract  the  peace  of  an 
already  mated  pair.§ 

Even  with  the  most  pugnacious  species  it  is  probable  that 
the  pairing  does  not  depend  exclusively  on  the  mere 
strength  and  courage  of  the  male;  for  such  males  are 
generally  decorated  v>^ith  various  ornaments,  which  often 
become  more  brilliant  during  the  breeding  -  season,  and 
which  are  sedulously  displayed  before  the  females.     The 

*Mr.  Blyth,  "  Land  and  Water."  1867,  p.  212 

f  Richardson  on  Tetrao  umbellus  "  Fauna  Bor.  Amer.:  Birds,  "^ 
1831.  p.  343.  L.  Lloyd,  "Game  Birds  of  Sweden."  1867.  pp.  22,  79, 
on  the  capercailzie  and  black-cock,  Brehm,  however,  asserts 
("  Thierleben,"  etc.,  B.  iv,  s.  352)  that  in  Germany  the  gray-hens  do 
not  generally  attend  the  Balzen  of  the  black-cocks,  but  this  is 
an  exception  to  the  common  rule;  possibly  the  hens  may  lie  hidden 
in  the  surrounding  bushes,  as  is  known  to  be  the  case  with  the  gray- 
hens  in  Scandinavia,  and  with  other  species  in  North  America. 

t  "  Ornithological  Biography,"  vol.  ii.  p.  275. 

§Brehm,  "Thierleben,"  etc..  B  iv,  1867,  p.  990.  Audubon, 
"Ornith.  Biography,"  vol.  ii,  p,  492. 


BIRDS,  417 

males  also  endeavor  to  charm  or  excite  their  mates  by  love- 
notes,  songs  and  antics ;  and  the  courtship  is,  in  many 
instances,  a  prolonged  affair.  Hence,  it  is  not  probable 
that  the  females  are  indifferent  to  the  charms  of  the  oppo- 
site sex,  or  that  they  are  invariably  compelled  to  yield  to 
the  victorious  males.  It  is  more  probable  that  the  females 
are  excited,  either  before  or  after  the  conflict,  by  certain 
males,  and  thus  unconsciously  prefer  them.  In  the  case  of 
Tetrao  umbellus,  a  good  observer  *  goes  so  far  as  to  believe 
that  the  battles  of  the  males  ^'  are  all  a  sham,  performed  to 
show  themselves  to  the  greatest  advantage  before  the 
admiring  females  who  assemble  around;  for  I  have  never 
been  able  to  find  a  maimed  hero,  and  seldom  more  than  a 
broken  feather. ^^  I  shall  have  to  recur  to  this  subject,  but 
I  may  here  add  that  with  the  Tetrao  ciipido  of  the  United 
States,  about  a  score  of  males  assemble  at  a  particular  spot, 
and,  stnitting  about,  make  the  whole  air  resound  with 
their  extraordinary  noises.  At  the  first  answer  from  a 
female  the  males  begin  to  fight  furiously,  and  the  weaker 
give  way;  but  then,  according  to  Audubon,  both  the  \dctors 
and  vanquished  search  for  the  female,  so  that  the  females 
must  either  then  exert  a  choice,  or  the  battle  must  be 
renewed.  So,  again,  with  one  of  the  field-starlings  of  the 
United  States  {Stnrnella  ludoviciana)  the  males  engage  in 
fierce  conflicts,  '^  but  at  the  sight  of  a  female  they  all  fly 
after  her  as  if  mad.^^  f 

Vocal  and  Instrumental  Music. — With  birds  the  voice 
serves  to  express  various  emotions,  such  as  distress,  fear, 
anger,  triumph,  or  mere  happiness.  It  is  apparently 
sometimes  used  to  excite  terror,  as  in  the  case  of  the 
hissing  noise  made  by  some  nestlings-birds.  Audubon  X 
relates  that  a  night-heron  (Ardea  nycticoraXy  Linn.)  which 
he  kept  tame,  used  to  hide  itself  when  a  cat  approached, 
and  then  "  suddenly  start  up  uttering  one  of  the  most 
frightful  cries,  apparently  enjoying  the  cat's  alarm  and 
flight."  The  common  domestic  cock  clucks  to  the  hen, 
and   the   hen  to   her  chickens,  when   a  dainty  morsel  is 

*  "Land  and  Water,"  July,  25,  1868,  p.  14. 

f  Audubon's  "  Ornitholog.  Biography;"  on  Tetrao  cupido,  vol.  ii, 
p.  492;  on  the  Sturnus,  vol.  ii,  p.  219. 

X  *'  Ornithological  Biograph.,"  vol.  v,  p.  601. 


418  THE  DESCENT  OF  MAN, 

found.  The  hen,  when  she  has  laid  an  egg,  "repeats  the 
same  note  very  often,  and  concludes  with  the  sixth  above, 
wliich  she  holds  for  a  longer  time;"*  and  thus  she  expresses 
her  joy.  Some  social  birds  apparently  call  to  each  other 
for  aid;  and  as  they  flit  from  tree  to  tree  the  flock  is  kept 
together  by  chirp  answering  chirp.  During  the  nocturnal 
migrations  of  geese  and  other  water-fowl  sonorous  clangs 
from  the  van  may  be  heard  in  tlie  darkness  overhead, 
answered  by  clangs  in  the  rear.  Certain  cries  serve  as 
danger  signals,  which,  as  the  sportsman  knows  to  his  cost, 
are  understood  by  the  same  species  and  by  others.  The 
domestic  cock  crows,  and  the  humming-bird  chirps  in 
triumph  over  a  defeated  rival.  The  true  song,  however,  of 
most  birds  and  various  strange  cries  are  chiefly  uttered 
during  the  breeding-season,  and  serve  as  a  charm,  or  merely 
as  a  call-note  to  the  other  sex. 

Naturalists  are  much  divided  with  respect  to  the  object 
of  the  singing  of  birds.  Few  more  careful  observers  ever 
lived  than  Montagu,  and  he  maintained  that  the  "  males 
of  song-birds  and  of  many  others  do  not  in  general  search 
for  the  female,  but  on  the  contrary,  their  business  in  the 
spring  is  to  perch  on  some  conspicuous  spot,  breathing  out 
their  full  and  amorous  notes,  which,  by  instinct,  the  female 
knows,  and  repairs  to  the  spot  to  choose  her  mate.'''t  Mr. 
Jenner  Weir  informs  me  that  this  is  certainly  the  case  with 
the  nightingale.  Bechstein,  who  kept  birds  during  his 
whole  life,  asserts  "  that  the  female  canary  always  chooses 
the  best  singer,  and  that  in  a  state  of  nature  the  female 
finch  selects  that  male  out  of  a  hundred  whose  notes  please 
her  most."];  There  can  be  no  doubt  that  birds  closely 
attend  to  each  other^s  song.  Mr.  Weir  has  told  me  of  the 
case  of  a  bullfinch  which  had  been  taught  to  pipe  a  German 
waltz,  and  who  was  so  good  a  performer  that  he  cost  ten 
guineas;  when  this  bird  was  first  introduced  into  a  room 
where  other  birds  were  kept  and  he  began  to  sing,  all  the 
others,  consisting  of  about   twenty  linnets   and   canaries, 

♦The  Hon.  Daines Barrington,  "  Philosoph.  Transact.,"  1773,  p.  252. 

f  "  Ornitliological  Dictionary."  1833,  p.  475. 

if "  Naturgescliiclite  der  Stubenvogel,"  1840,  s.  4.  Mr.  Harrison 
Weir  likewise  writes  to  me:  "  I  am  informed  that  the  best  singing 
males  generally  get  a  mate  first,  when  they  are  bred  in  the  same 
room." 


BIRDS.  419 

ranged  themselves  on  the  nearest  side  of  their  cages  and  list- 
ened with  the  greatest  interest  to  the  new  performer.  Many 
naturalists  believe  that  the  singing  of  birds  is  almost  ex- 
clusively **  the  eifect  of  rivalry  and  emulation/^  and  not 
for  the  sake  of  charming  their  mates.  This  was  the 
opinion  of  Daines  Barrington  and  White  of  Selborne,  who 
both  especially  attended  to  this  subject.*  Barrington, 
liowever,  admits  that  "superiority  in  song  gives  to  birds  an 
amazing  ascendency  over  others,  as  is  well  known  to  bird- 
catchers." 

It  is  certain  that  there  is  an  intense  degree  of  rivalry 
between  the  males  in  their  singing.  Bird  fanciers  match 
their  birds  to  see  which  will  sing  longest;  and  I  was  told 
by  Mr.  Yarrell  that  a  first-rate  bird  will  sometimes  sing 
till  he  drops  down  almost  dead,  or  according  to  Bechstein,f 
quite  dead  from  rupturing  a  vessel  in  the  lungs.  What- 
ever the  cause  may  be,  male  birds,  as  I  hear  from  Mr. 
Weir,  often  die  suddenly  during  the  season  of  song.  That 
the  habit  of  singing  is  sometimes  quite  independent  of  love 
is  clear,  for  a  sterile,  hybrid  canary-bird  has  been  described^ 
as  singing  while  viewing  itself  in  a  mirror  and  then  dash- 
ing at  its  own  image ;  it  likewise  attacked  with  fury 
a  female  canary  when  put  into  the  same  cage.  The 
jealousy  excited  by  the  act  of  singing  is  constantly  taken 
advantage  of  by  bird-catchers;  a  male,  in  good  song,  is 
hidden  and  protected,  while  a  stuffed  bird  surrounded  by 
limed  twigs  is  expose  to  view.  In  this  manner,  as  Mr. 
Weir  informs  me,  a  man  has  in  the  course  of  a  single  day 
caught  fifty,  and  in  one  instance  seventy  male  chaffinches. 
The  power  and  inclination  to  sing  differ  so  greatly  with  birds 
that  although  the  price  of  an  ordinary  male  chaffinch  is  only 
sixpence,  Mr.  Weir  saw  one  bird  for  which  the  bird-catcher 
asked  three  pounds  ;  the  test  of  a  really  good  singer  being 
that  it  will  continue  to  sing  while  the  cage  is  swung  round 
the  owner's  head. 

That  male  birds  should  sing  from  emulation  as  well  as 
for  charming  the  female  is  not  at  all  incompatible;  and  it 
might  have   been  expected   that  these  two  habits  would 

*  "Philosophical  Transactions,"  1773,  p.  263.     White's  "Natural 
History  of  Selborne,"  1825,  vol.  i,  p.  246. 
t  "Naturgesch.  der  StubenvOgel,"  1840,  s.  252. 
tMr.  Bold,  "Zoologist,"  1843-44,  p.  659, 


420  THE  DESCENT  OF  MAN. 

have  occurred,  like  those  of  display  and  pugnacity.  Some 
authors,  however,  argue  that  the  song  of  the  male  cannot 
serve  to  charm  the  female,  because  the  females  of  some 
few  species,  such  as  of  the  canary,  robin,  lark  and  bull- 
finch, especially  when  in  a  state  of  widowhood,  as  Bech- 
stein  remarks,  pour  forth  fairly  melodious  strains.  In 
some  of  these  cases  the  habit  of  singing  may  be  in  part 
attributed  to  the  females  having  been  highly  fed  and  con- 
fined,* for  this  disturbs  all  the  usual  functions  connected 
with  the  reproduction  of  the  species.  Many  instances 
have  already  been  given  of  the  partial  transference  of  sec- 
ondary masculine  characters  to  the  females,  so  that  it  is 
not  at  all  surprising  that  the  females  of  some  species  should 
possess  the  power  of  song.  It  has  also  been  argued  that 
the  song  of  the  male  cannot  serve  as  a  charm,  because  the 
males  of  certain  species,  for  instance  of  the  robin,  sing 
during  the  autumn,  f  But  nothing  is  more  common  than 
for  animals  to  take  pleasure  in  practicing  whatever  instinct 
they  follow  at  other  times  for  some  real  good.  How  often 
do  we  see  birds  which  fly  easily  gliding  and  sailing  through 
the  air  obviously  for  pleasure?  The  cat  plays  with  the 
captured  mouse  and  the  cormorant  with  the  captured  fish. 
The  weaver-bird  (Ploceus),  when  confined  in  a  cage, 
amuses  itself  by  neatly  weaving  blades  of  grass  between  the 
wires  of  its  cage.  Birds  which  habitually  fight  during  the 
breeding-season  are  generally  ready  to  fight  at  all  times; 
and  the  males  of  the  capercailzie  sometimes  hold  their 
Balzen  or  leks  at  the  usual  place  of  assemblage  during  the 
autumn.  J  Hence  it  is  not  at  all  surprising  that  male  birds 
should  continue  singing  for  their  own  amusement  after  the 
season  for  courtship  is  over. 

As  shown  in  a  previous  chapter,  singing  is  to  a  certain 
extent  an  art,  and  is  much  improved  by  practice.  Birds 
can  be  taught  various  tunes,  and  even  the  unmelodious 
sparrow  has  learned  to  sing  like  a  linnet.  They  acquire 
the  song  of  their  foster  parents,  §  and  sometimes  that  of 

*D.  Barrington,  "Phil.  Transact.,"  1773,  p.  262.  Bechstein, 
"Stubenvogel,"  1840.  s.  4. 

f  This  is  likewise  the  case  with  the  water-ouzel;  see  Mr.  Hepburn 
in  the  "Zoologist,"  1845-46,  p.  1068. 

X  L.  Lloyd,  "  Game  Birds  of  Sweden,"  1867,  p.  25. 

§  Barrington,  ibid,  p.  264,  Bechstein,  ibid,  s.  5. 


BntDS.  421 

their  neighbors.*  All  tlie  common  songsters  belong  to  the 
Order  of  Insessores,  and  their  Yocal  organs  are  much  more 
complex  than  those  of  most  other  birds;  yet  it  is  a  singular 
fact  that  some  of  the  Insessores,  such  as  ravens,  crows,  and 
magpies,  possess  the  proper  apparatus,!  though  they  never 
sing,  and  do  not  naturally  modulate  their  voices  to  any 
great  extent.  Hunter  asserts  X  that  with  the  true  songsters 
the  muscles  of  the  larynx  are  stronger  in  the  males  than  in 
the  females ;  but  with  this  slight  exception  there  is  no  dif- 
ference in  the  vocal  organs  of  the  two  sexes,  although  the 
males  of  most  species  sing  so  much  better  and  more  con- 
tinuously than  the  females. 

It  is  remarkable  that  only  small  birds  properly  sing. 
The  Australian  genus  Menura,  however,  must  be  excepted; 
for  the  Menura  Alberti,  which  is  about  the  size  of  a  half- 
grown  turke}' ,  not  only  mocks  other  birds,  but  *'  its  own 
whistle  is  exceedingly  beautiful  and  varied."  The  males 
congregrte  and  form  ^'  corroborying  places,"  where  they 
sing,  raising  and  spreading  their  tails  like  peacocks,  and 
drooping  their  wings.  §  It  is  also  remarkable  that  birds 
which  sing  well  are  rarely  decorated  with  brilliant  colors 
or  other  ornaments.  Of  our  British  birds,  excepting  the 
bullfinch  and  goldfinch,  the  best  songsters  are  plain- 
colored.  The  kingfisher,  bee-eater,  roller,  hoopoe,  wood- 
pecker, etc.,  utter  harsh  cries  ;  and  the  brilliant  birds  of 
the  tropics  are  hardly  ever  songsters.  ||  Hence  bright 
colors  and  the  power  of  song  seem  to  replace  each  other. 
We  can  perceive  that  if  the  plumage  did  not  vary  in 
brightness,  or  if  bright  colors  were  dangerous  to  the 
species,  other  means  would  be  employed  to  charm  the 
females;  and  melody  of  voice  offers  one  such  means. 

In  some  birds  the  vocal  organs  differ  greatly  in  the  two 

*  Bureau  de  la  Malle  gives  a  curious  instance  ('*  Annales  des  Sc. 
Nat.,"  3d  series,  Zoolog.,  torn,  x,  p.  118)  of  some  wild  blackbirds  in 
his  garden  in  Paris,  which  naturally  learned  a  republican  air  from  a 
caged  bird, 

f  Bishop,  in  *'  Todd's  Cyclop,  of  Anat.  and  Phys.,"  vol.  iv,  p.  1496. 

J  As  stated  by  Barrington  in  "  Philosoph.  Transact.,"  1773,  p.  ^62. 

§  Gould,  "  Hand-book  to  the  Birds  of  Australia,"  vol.  i,  1865,  pp. 
308-310.  See  also  Mr.  T.  W.  Wood  in  the  "  Student,"  April,  1870, 
p.  125. 

I  See  remarks  to  this  effect  in  Gould's  "Introduction  to  the  Tro- 
chilidse/'  1861,  p.  22. 


422 


THE  DESCENT  OF  MAN. 


sexes.  In  the  Tetrao  cupido  (fig  39)  the  male  has  two 
bare,  orange- colored  sacks,  one  on  each  side  of  the  neck  ; 
and  these  are  largely  inflated  when  the  male,  during  the 
breeding-season,  makes  his  curious  hollow  sound,  audible 
at  a  great  distance.     Audubon  proved  that  the  sound  was 


'^^^g^*'- 


intimately  connected  with  this  apparatus  (which  reminds 
us  of  the  air-sacks  on  each  side  of  the  mouth  of  cer- 
tain male  frogs),  for  he  found  that  the  sound  was 
much  diminished  when  one  of  the  sacks  of  a  tame 
bird     was    pricked,    and    when     both    were    pricked    it 


BIRDS,  423 

Was  altogether  stopped.  The  female  has  "a  some- 
what similar,  though  smaller  naked  space  of  skin 
on  the  neck  ;  but  this  is  not  capable  of  inflation."* 
The  male  of  another  kind  of  grouse  ( Tetrao  urophasianus), 
while  courting  the  female,  has  his  "  bare  yellow  oesophagus 
inflated  to  a  prodigious  size,  fully  half  as  large  as  the  body;" 
and  he  then  utters  various  grating,  deep,  hollow  tones. 
With  his  neck-feathers  erect,  his  wings  lowered,  and  buzz- 
ing on  the  ground,  and  his  long  pointed  tail  spread  out 
like  a  fan,  he  displays  a  variety  of  grotesque  attitudes.  Tlie 
oesophagus  of  the  female  is  not  in  any  way  remarkable. f 

It  seems  now  well  made  out  that  the  great  throat-pouch 
of  the  European  male  bustard  {Otis  tarda),  and  of  at  least 
four  other  species,  does  not,  as  was  formerly  supposed,  serve 
to  hold  water,  but  is  connected  with  the  utterance  during 
the  breeding-season  of  a  peculiar  sound  resembling  '^  oak."| 
A  crow-like  bird  inhabiting  South  America,  Cephalopteriis 
ornatus  (fig.  40),  is  called  the  umbrella-bird  from  its  im- 
mense top-knot,  formed  of  bare  white  quills  surmounted  by 
dark-blue  plumes,  which  it  can  elevate  into  a  great  dome 
no  less  than  five  inches  in  diameter,  covering  the  whole 
head.  This  bird  has  on  its  neck  a  long,  thin,  cylindrical, 
fleshy  appendage,  which  is  thickly  clothed  with  scale-like 
blue  feathers.  It  probably  serves  in  part  as  an  ornament, 
but  likewise  as  a  resounding  apparatus;  for  Mr.  Bates  found 
that  it  is  connected  ^*  with  an  unusual  development  of  the 
trachea  and  vocal  organs."  It  is  dilated  when  the  bird 
utters   its  singularly  deep,  loud  and  long-sustained  fluty 

*"The  Sportsman  and  Naturalist  in  Canada,"  by  Ma j.  W.  Ross 
King,  1866,  pp.  144-146.  Mr.  T.  W.  Wood  gives  in  the  "  Student" 
(April,  1870,  p.  116)  an  excellent  account  of  tlie  attitude  and  babits 
of  tbis  bird  during  its  courtsbip.  He  states  tbat  tbe  ear-tufts  or 
neck-plumes  are  erected  so  tbat  tbey  meet  over  tbe  crown  of  tbe 
bead.     See  bis  drawing,  fig.  39. 

f  Ricbardson,  '*  Fauna  Bor.  American:  Birds,"  1831,  p.  359,  Audu- 
bon, ibid,  vol.  iv,  p.  507. 

X  Tbe  following  papers  bave  been  lately  written  on  tbis  subject: 
Prof.  A.  Newton  in  tbe  "  Ibis,"  1862,  p.  107;  Dr.  Cullen,  ibid,  1865, 
p.  145;  Mr.  Flower  in  "Proc.  Zool.  Soc,"  1865,  p.  747;  and  Dr. 
Murie  in  "Proc.  Zool.  Soc,"  1868,  p.  471.  In  tbis  latter  paper  an 
excellent  figure  is  given  of  tbe  male  Australian  bustard  in  full  dis- 
play witb  tbe  sack  distended.  It  is  a  singular  fact  tbat  tbe  sack  is 
not  developed  in  all  tbe  males  of  tbe  same  species. 


424 


THE  DESCENT  OF  MAN. 


note.     The  head-crest  and  neck-appendage  are  rudimentary 
in  the  female.* 

The  vocal  organs  of  various  web-footed  and  wading  birds 
are  extraordinarily  complex,  and  differ  to  a  certain  extent 
in  the  two  sexes.     In  some  cases  the  trachea  is  convoluted. 


Fig.  40.    The  Umbrella-bird  or  Cephalopterus  ornatus,  male  (from  Brehui). 

like  a  French  horn,  and  is  deeply  embedded  in  the  sternum. 
In  the  wild  swan  {Cygnus  fertis)  it  is  more  deeply 
embedded  in  the  adult  male  than  in  the  adult  female  or 


*  Bates.  "  The  Naturalist  on  the  Amazons,"  1863,  vol.  ii,  p.  284; 
Wallace,  in  "  Proc.  Zool.  Soc,"  1850,  p.  206.  A  new  species,  with 
a  still  larger  neck  appendage  (O.  penduUger),  has  lately  been  dis- 
covered, see  ''  Ibis,"  vol.  i,  p.  457. 


BIBBS.  4^5 

young  male.  In  the  male  Merganser  the  enlarged  portion 
of  the  trachea  is  furnished  with  an  additional  pair  of  mus- 
cles.* In  one  of  the  ducks,  however,  namely.  Anas 
punctata,  the  bony  enlargement  is  only  a  little  more  devel- 
oped in  the  male  than  in  the  female,  f  But  the  meaning 
of  these  differences  in  the  trachea  of  the  two  sexes  of  the 
Anatidae  is  not  understood ;  for  the  male  is  not  always  the 
more  vociferous;  thus  with  the  common  duck,  the  male 
hisses,  while  the  female  utters  a  loud  quack.  |  In  both 
sexes  of  one  of  the  cranes  ( Grus  virgo)  the  trachea  pene- 
trates the  sternum,  but  presents  "  certain  sexual  modifica- 
tions." In  the  male  of  the  black  stork  there  is  also  a  well- 
marked  sexual  difference  in  the  length  and  curvature  of  the 
bronchi.  §  Highly  important  structures  have,  therefore,  in 
these  cases  been  modified  according  to  sex. 

It  is  often  difficult  to  conjecture  whether  the  many 
strange  cries  and  notes  uttered  by  male  birds  during  the 
breeding-season  serve  as  a  charm  or  merely  as  a  call  to  the 
female.  The  soft  cooing  of  the  turtle-dove  and  of  many 
pigeons,  it  may  be  presumed,  pleases  the  female.  When  the 
female  of  the  wild  turkey  utters  her  call  in  the  morning,  the 
male  answers  by  a  note  which  differs  from  the  gobbling 
noise  made,  when  with  erected  feathers,  rustling  wings  and 
distended  wattles,  he  puffs  and  struts  before  her.  ||  The 
spel  of  the  black-cock  certainly  serves  as  a  call  to  the 
female,  for  it  has  been  known  to  bring  four  or  five  females 
from  a  distance  to  a  male  under  confinement;  but  as  the 
black-cock  continues  his  spel  for  hours  during  successive 
days,  and  in  the  case  of  the  capercailzie  "  with  an  agony 
of  passion,"  we  are  led  to  suppose  that  the  females  which 
are  present  are  thus  charmed.il     The  voice  of  the  common 

♦Bishop,  in  Todd's  "  Cyclop,  of  Anat.  and  Phys.,"  vol.  iv,  p.  1499. 

f  Prof.  Newton,  "  Proc.  Zoolog.  Soc.,"  1871,  p.  651. 

X  The  spoonbill  (Platalea)  has  its  trachea  convoluted  into  a  figure 
of  eight,  and  yet  this  bird  (Jerdon,  "  Birds  of  India,"  vol.  iii,  p.  763) 
is  mute;  but  Mr.  Blyth  informs  me  that  the  convolutions  are  not 
constantly  present,  so  that  perhaps  they  are  now  tending  toward 
abortion. 

§  '*  Elements  of  Comp.  Anat.,"  by  R.  Wagner,  Eng.  translat.,  1845, 
p.  111.  With  respect  to  the  swan,  as  given  above,  Tarrell's  "Hist, 
of  British  Birds,"  2d  edit,  1845,  vol.  iii,  p.  193. 

I C.  L.  Bonaparte,  quoted  in  the  "  Naturalist  Library;  Birds,"  vol. 
xiv,  p.  126. 

^L.  Lloyd,  "  The  Game  Birds  of  Sweden,"  etc.,  1867,  pp.  22,  81. 


426  TSE  DESCENT  OF  MAN. 

rook  is  known  to  alter  during  the  breeding-season,  and  is 
therefore  in  some  way  sexual.*  But  what  shall  we  say 
about  the  harsh  screams  of,  for  instance,  some  kinds  of 
macaws;  have  these  birds  as  bad  taste  for  musical  sounds 
as  they  apparently  have  for  color.  Judging  by  the  inhar- 
monious contrast  of  their  bright  yellow  and  blue  plumage? 
It  is  indeed  possible  that  without  any  advantage  being  thus 
gained,  the  loud  voices  of  many  male  birds  may  be  the 
result  of  the  inherited  effects  of  the  continued  use  of  their 
vocal  organs  when  excited  by  the  strong  passions  of  love, 
jealousy  and  rage;  but  to  this  point  we  shall  recur  when  we 
treat  of  quadrupeds. 

We  have  as  yet  spoken  only  of  the  voice,  but  the  males 
of  various  birds  practice,  during  their  courtship,  what  may 
be  called  instrumental  music.  Peacocks  and  birds  of 
paradise  rattle  their  quills  together.  Turkey-cocks  scrape 
their  wings  against  the  ground,  and  some  kinds  of  grouse 
thus  produce  a  buzzing  sound.  Another  North  American 
grouse,  the  Tetrao  tmibellus,  when  with  his  tail  erect, 
his  ruffs  displayed  '^  he  shows  off'  his  finery  to  the  females 
who  lie  hid  in  the  neighborhood,^^  drums  by  rapidly  striking 
his  wings  together  above  his  back,  according  to  Mr.  R. 
Haymond,  and  not,  as  Audubon  thought,  by  striking  them 
against  his  sides.  The  sound  thus  produced  is  compared 
by  some  to  distant  thunder  and  by  others  to  the  quick  roll 
of  a  drum.  The  female  never  drums,  '^  but  flies  directly 
to  the  place  where  the  male  is  thus  engaged.^'  The  male 
of  the  Kali j -pheasant  in  the  Himalayas,  **  often  makes  a  sin- 
gular drumming  noise  with  his  wings,  not  unlike  the  sound 
produced  by  shaking  a  stiff  piece  of  cloth."  On  the  west 
coast  of  Africa  tlie  little  black-weavers  (Ploceus?)  congre- 
gate in  a  small  party  on  the  bushes  round  a  small  open  space 
and  sing  and  glide  through  the  air  with  quivering  wings, 
"which  make  a  rapid  whirring  sound  like  a  child's  rattle." 
One  bird  after  another  thus  performs  for  hours  together 
but  only  during  the  courting-season.  At  this  season,  and 
at  no  other  time,  the  males  of  certain  night-jars  (Caprimul- 
gus)  make  a  strange  booming  noise  with  their  wings.  The 
various  species  of  woodpeckers  strike  a  sonorous  branch 
with  their  beaks  with  so  rapid  a  vibratory  movement  that 

*Jenner,  "  Philosoph,  Transactions,"  1824,  p.  20. 


BIRDS.  42? 

"  the  head  appears  to  be  in  two  places  at  once/'  The  sound 
thus  produced  is  audible  at  a  considerable  distance,  but 
cannot  be  described;  and  I  feel  sure  that  its  source  would 
never  be  conjectured  by  any  one  hearing  it  for  the  first 
time.  As  this  jarring  sound  is  made  chiefly  during  the 
breeding-season,  it  has  been  considered  as  a  love-song;  but 
it  is  perhaps  more  strictly  a  love-call.  The  female,  when 
driven  from  her  nest,  has  been  observed  thus  to  call  her 
mate,  who  answered  in  the  same  manner  and  scon  appeared. 
Lastly,  the  male  hoopoe  ( Upupa  epojjs)  combines  vocal 
and  instrumental  music;  for  during  the  breeding-season 
this  bird,  as  Mr.  Swinhoe  observed,  first  draws  in  air  and 
then  taps  the  end  of  its  beak  perpendicularly  down  against 
a  stone  or  the  trunk  of  a  tree,  ''  when  the  breath  being 
forced  down  the  tubular  bill  produces  the  correct  sound." 
If  the  beak  is  not  thus  struck  against  some  object  the 
sound  is  quite  different.  Air  is  at  the  same  time  swallowed 
and  the  oesophagus  thus  becomes  much  swollen;  and  this 
probably  acts  as  a  resonator,  not  only  with  the  hoopoe  but 
with  pigeons  and  other  birds.* 

In  the  foregoing  cases  sounds  are  made  by  the  aid  of 
structures  already  present  and  otherwise  necessary;  but  in 
the  following  cases  certain  feathers  have  been  specially 
modified  for  the  express  purpose  of  producing  sounds. 
The  drumming,  bleating,  neighing  or  thundering  noise  (as 
expressed  by  different  observers)  made  by  the  common 
snipe  {Scolopax  gallinago)  must  have  surprised  every  one 
who  has  ever  heard  it.  This  bird,  during  the  pairing- 
season,  flies  to  **  perhaps  a  thousand  feet  in  height,"  and 
after  zig-zagging  about  for  a  time  descends  to  the  earth  in 

*For  the  foregoing  facts  see,  on  birds  of  paradise,  *' Brelim, 
"  Thierleben,"  Band  iii,  s.  325.  On  grouse,  Richardson,  "Fauna 
Bor.  Americ:  Birds,"  pp.  343,  359;  Maj.  W.  Ross  King,  "The 
Sportsman  in  Canada,"  1866,  p.  156;  Mr.  Raymond,  in  Prof.  Cox's 
"Geol.  Survey  of  Indiana,"  p.  227;  Audubon,  "American  Ornitli- 
olog.  Biograph.,"  vol.  i,  p.  216.  On  the  Kalij- pheasant,  Jerdon, 
"Birds  of  India,"  vol.  iii,  p.  533.  On  the  weavers,  "Livingstone's 
Expedition  to  the  Zambesi,"  1865,  p.  425.  On  woodpeckers,  Mac- 
gillivray,  "  Hist,  of  British  Birds,"  vol.  iii,  1840,  pp.  84,  88,  89, 
95.  On  the  hoopoe,  Mr.  Swinhoe,  in  "  Proc.  Zoolog.  Soc,"  June  23, 
1863,  1871,  p.  348.  On  the  night-jar,  Audubon,  ibid,  vol. 
ii,  p.  255,  and  "American  Naturalist,"  1873,  p.  672.  The  English 
night-jar  likewise  makes  in  the  spring  a  curious  noise  during  its 
rapid  flight. 


428 


THE  DESCENT  OF  MAN. 


a  curved  line  with  outspread  tail  and  quivering  pinions 
and  surprising  velocity.  The  sound  is  emitted  only  during 
this  rapid  descent.  No  one  was  able  to  explain  the  cause 
until  M.  Meves  observed  that  on  each  side  of  the  tail  the 
outer  feathers  are  peculiarly  formed   (fig.  41),  having  a 


Fig.  41.  Outer  tail-feather  of  Scolopax  gallinago  (from  "  Proc.  Zool.  Soc,"  1858.) 

stiff  saber-shaped  shaft  with  the  oblique  barbs  of  unusual 
length,  the  outer  webs  being  strongly  bound  together.  He 
found  that  by  blowing  on  these  feathers,  or  by  fastening 
them  to  a  long,  thin  stick  and  waving  them  rapidly  through 
the  air,  he  could  reproduce  the  drumming  noise  made  by 
the  living  bird.  Both  sexes  are  furnished  with  these  feath- 
ers, but  they  are  generally  larger  in  the  male  than  in  the 
female  and  emit  a  deeper  note.  In  some  species,  as  in 
S.  frenata  (fig.  42),  four  feathers,  and  in  S.  javensis  (fig. 
43),  no  less  than  eight  on  each  side  of  the  tai'  are  greatly 


Fig.  42.    Outer  tail-feather  of  Scolopax  frenata. 


Fig.  43.    Outer  tail-feather  of  Scolopax  javensis. 

modified.  Different  tones  are  emitted  by  the  feathers  of 
the  different  species  when  waved  through  the  air;  and  the 
Scolopax  Wilsonii  of  the  United  States  makes  a  switching 
noise  while  descending  rapidly  to  the  earth.* 

In  the  male  of  the  Chammpetes  unicolor  (a  large  galli- 
naceous bird  of  America),  the  first  primary  wing-feather  is 
arched  toward  the  tip  and  is  much  more  attenuated  than  in 

*See  M.  Meves'  interesting  paper  in  "Proc.  Zool.  Soc,"  1858,  p. 
199.  For  the  habits  of  the  snipe,  Macgillivray,  "  Hist.  British 
Birds,"  vol.  iv,  p.  371.  For  the  American  snipe,  Capt.  Blakiston, 
"  Ibis,"  vol.  V,  1863,  p.  131. 


BIRDS.  429 

the  female.  In  an  allied  bird,  the  Penelope  nigra,  Mr. 
Salvin  observed  a  male,  which,  while  it  flew  downward 
*^with  outstretched  wings,  gave  forth  a  kind  of  crashing, 
rushing  noise,"  like  the  falling  of  a  tree.*  The  male 
alone  of  one  of  the  Indian  bustards  {Sypheotides  auritus) 
has  its  primary  wing-feathers  greatly  acuHiinated;  and  the 
male  of  an  allied  species  is  known  to  make  a  humming 
noise  while  courting  the  female,  f  In  a  widely  different 
group  of  birds,  namely,  humming-birds,  the  males  alone  of 
certain  kinds  liave  either  the  shafts  ^^_ 
of  their  primary  wing  feathers  •^H>^'??^>ito^^''^~' 
broadly  dilated,  or  the  webs  ab- 
ruptly excised  toward  the  extrem- 
ity. The  male,  for  instance,  of 
Selas2)horus  platycercus,  when 
adult,  has  the  first  primary  wing-  Fig.  44    Primary  wing-feather 

-,,'        /„  ji\,i  "^-T         of  a  humming  bird,  the /Se/o^- 

feather     (fig.      44)      thus     excised.       phorus   platycerons    (from     a 

While  flying  from  flower  to  flower     |«t  'tL^ of  mkt- ;  \SS?r 

he  makes  *^  a   shrill,  almost  whist-      figure,  corresponding  feather 

ling  noise ;";[  but  it  did  not  appear     ^    emae. 

to  Mr.  Salvin  that  the  noise  was  intentionally  made. 

Lastly,  in  several  species  of  a  sub-genus  of  Pipra  or 
Manakin,  the  males,  as  described  by  Mr.  Sclater,  have  their 
secondary  wing-feathers  modified  in  a  still  more  remarkable 
manner.  In  the  brilliantly-colored  P.  deliciosa  the  first 
three  secondaries  are  thick-stemmed  and  curved  toward  the 
-body;  in  the  fourth  and  fifth  (fig.  45,  a)  the  change  is 
greater;  and  in  the  sixth  and  seventh  {b,  c)  the  shaft  '^is 
thickened  to  an  extraordinary  degree,  forming  a  solid  horny 
lump."  The  barbs  also  are  greatly  changed  in  shape,  in 
comparison  with  the  corresponding  feathers  (d,  e,  f)  in  the 
female.  Even  the  bones  of  the  wing,  which  support  these 
singular  feathers  in  the  male,  are  said  by  Mr.  Fraser  to  be 
much  thickened.  These  little  birds  make  an  extraordinary 
noise,  the  first  "  sharp  note  being  not  unlike  the  crack  of  a 
whip."§ 

*Mr.  Salvin,  in  "  Proc.  Zool.  Soc,"  1867,  p.  160.  I  am  much 
indebted  to  this  distinguished  ornithologist  for  sketches  of  the 
feathers  of  the  Chamaepetes  and  for  other  information. 

f  Jerdon,  "Birds  of  India,"  vol.  iii,  pp.  618,  621. 

^Qould,  "Introd'iction  to  the  Trochilidae,"  1861,  p.  49.  Salvin, 
"  Proc.  Zoolog.  Soc  ,"  1867,  p.  160. 

i? Sclater,  in  "Proc.  Zool.  Soc,"  1860,  p.  90,  and  in  "Ibis,"  vol. 
iv,  1863,  p.  175.    Also  Salvin,  in  "  Ibis,"  1860,  p.  37. 


430 


THE  DESCENT  OF  MAN, 


The  diversity  of  the  sounds,  both  vocal  and  instmmental, 
made  by  the  males  of   many  birds  during  the  breeding- 


Fig.  45.  Secondary  winjr-feathers  of  Pipra  deliciosa  (from  Mr.  Sclater,  in  "Proo. 
Zool.  Soc,"  18(i6.  The  three  upper  feathers,  a,  b,  c,  from  the  male;  the  three 
lower  correspondinj?  feathers,  d,  e,f,  from  the  female. 

a  and  d,  fifth  secondary  wing-feather  of  male  and  female,  upper  surface. 

b  and  e,  sixth  secondary,  upper  surface. 

c  and/,  seventh  seconaary,  upper  surface. 


season,  and  the  diversity  of  the  means  for  producing  such 
sounds,  are  highly  remarkable.  We  thus  gain  a  high  idea 
of  their  importance  for  sexual  purposes,  and  are  reminded 
of  the  conclusion  arrived  at  as  to  insects.  It  is  not  difficult 
to  imagine  the  steps  by  which  the  notes  of  a  bird,  primarily 
used  as  a  mere  call  or  for  some  other  purpose,  might  have 


BIRDS.  431 

been  improved  into  a  melodious  love-song.  In  the  case  of 
the  modified  feathers,  by  which  the  drumming,  whistling, 
or  roaring  noises  are  produced,  we  know  that  some 
birds  during  their  courtship  flutter,  shake,  or  rattle 
their  unmodified  feathers  together;  and  if  the  females  were 
led  to  select  the  best  performers,  the  males  which  possessed 
the  strongest  or  thickest,  or  most  attenuated  feathers, 
situated  on  any  part  of  the  body,  would  be  the  most  suc- 
cessful; and  thus  by  slow  degrees  the  feathers  might  be 
modified  to  almost  any  extent.  The  females,  of  course, 
would  not  notice  each  slight  successive  alteration  in  shape, 
but  only  the  sounds  thus  produced.  It  is  a  curious  fact 
that  in  the  same  class  of  animals,  sounds  so  different  as  the 
drumming  of  the  snipe's  tail,  the  tapping  of  the  wood- 
pecker's beak,  the  harsh  trumpet-like  cry  of  certain  Avater- 
fowl,  the  cooing  of  the  turtle-dove,  and  the  song  of  the 
nightingale,  should  all  be  pleasing  to  the  females  of  the 
several  species.  But  we  must  not  judge  of  the  tastes  of 
distinct  species  by  a  uniform  standard;  nor  must  we  judge 
by  the  standard  of  man's  taste.  Even  with  man,  we  should 
remember  what  discordant  noises,  the  beating  of  tomtoms 
and  the  shrill  notes  of  reeds,  please  the  ears  of  savages. 
Sir  S.  Baker  remarks,*  that  ^'  as  the  stomach  of  the  Arab 
prefers  the  raw  meat  and  reeking  liver  taken  hot  from  the 
animal,  so  does  his  ear  prefer  his  equally  coarse  and  dis- 
cordant music  to  all  other.'' 

Love  Antics  and  Dances. — The  curious  love  gestures  of 
some  birds  have  already  been  incidentally  noticed;  8o 
that  little  need  here  be  added.  In  Xorthern  Amer- 
ica large  numbers  of  a  grouse,  the  Tetrao  phasianellus, 
meet  every  morning  during  the  breeding-season  on 
a  selected  level  spot,  and  here  they  run  round  and 
round  in  a  circle  of  about  fifteen  or  twenty  feet  in  diam- 
eter, so  that  the  ground  is  worn  quite  bare,  like  a  fairy- 
ring.  In  these  partridge-dances,  as  they  are  called  by  the 
hunters,  the  birds  assume  the  strangest  attitudes,  and  run 
round,  some  to  the  left  and  some  to  the  right.  Audu- 
bon describes  the  males  of  a  heron  (Ardea  Jiero- 
dias)  as  walking  about  on  their  long  legs  with 
great    dignity    before   the   females,    bidding   defiance   to 

*  "  The  Nile  Tributaries  of  Abyssinia,"  1867,  p.  203. 


432  TEE  DESCENT  OF  MAN, 

their  rivals.  With  one  of  the  disgusting  carrion- 
vultures  (Cathartes  jota)  the  same  naturalist  states  that 
"  the  gesticulations  and  parade  of  the  males  at  the  begin- 
ning of  the  love  season  are  extremely  ludicrous/'  Certain 
birds  perform  their  love  antics  on  the  wing,  as  we  have 
seen  with  the  black  African  weaver,  instead  of  on  the 
ground.  During  the  spring  our  little  white  throat  {Sylvia 
cinerea)  often  rises  a  few  feet  or  yards  in  the  air  above 
some  bush  and  "  flutters  with  a  fitful  and  fantastic  motion, 
singing  all  the  while,  and  then  droj)S  to  its  perch."  'J'lie 
great  English  bustard  throws  himself  into  indescribably 
odd  attitudes  while  courting  the  female,  as  has  been  figured 
by  AVolf.  An  allied  Indian  bustard  {Otis  bengalensis)  at 
such  times  "rises  perpendicularly  into  the  air  with  a 
hurried  flapping  of  his  wings,  raising  his  crest  and  puffing 
out  the  feathers  of  his  neck  and  breast  and  then  drops  to 
the  ground;"  he  repeats  this  maneuver  several  times,  at 
the  same  time  humming  in  a  peculiar  tone.  Such  females 
as  happen  to  be  near  "  obey  this  saltatory  summons,"  and 
when  they  approach  he  trails  his  wings  and  spreads  his  tail 
like  a  turkey-cock.* 

But  the  most  curious  case  is  afforded  by  three  allied 
genera  of  Australian  birds,  the  famous  bower-birds — no 
doubt  the  co-descendants  of  some  ancient  species  which 
first  acquired  the  strange  instinct  of  constructing  bowers 
for  performing  their  love  antics.  The  bowers  (fig,  4f)) 
which,  as  we  shall  hereafter  see,  are  decorated  with  feath- 
ers, shells,  bones  and  leaves,  are  built  on  the  ground  for 
the  sole  purpose  of  courtship,  for  their  nests  are  formed  in 
trees.  Both  sexes  assist  in  the  erection  of  the  bowers,  but 
the  male  is  the  principal  workman.  So  strong  is  this 
instinct  that  it  is  practiced  under  confinement,  and  Mr. 
Strange  has  describedf  the  habits  of  some  satin  bower-birds 
which  he  kept  in  an  aviary  in  New  South  Wales.     "At 

*For  Tetrao  phasianellus,  see  Richardson,  "  Fauna,  Bor.  Amer- 
ica," p.  361,  and  for  further  particulars,  Capt.  Bha,kiston,  "  Ibis," 
1863,  p.  125.  For  the  Cathartes  and  Ardea,  Audabon,  "  Ornith. 
Biography,"  vol.  ii,  p,  51,  and  vol.  iii,  p.  89.  On  the  white-throat, 
Macgillivray,  ''Hist.  British  Birds,"  vol.  ii,  p.  354.  On  the  Indian 
bustard,  Jerdon,  "  Birds  of  India,"  vol.  iii,  p.  618. 

f  Gould,  "Hand-book  to  the  Birds  of  Australia,"  vol.  i,  pp.  444, 
449,  455.  The  bower  of  the  satin  bower-bird  may  be  seen  in  the 
Zoological  Societjr's  Gardens,  Regent  Park, 


BIRDS.  433 

times  the  male  will  chase  the  female  all  over  the  aviary. 


:Mii 


then  go  to  the  bower,  pick  up  a  gay  feather  or  a  large  leaf, 
utter  a  curious  kind  of  note,  set  all  his  feathers  erect,  run 
round  the  bower  and  become  so  excited  that  his  eyes  appear 


434  THE  DESCENT  OF  MAN, 

ready  to  start  from  his  head;  he  continues  opening  first  one 
wing,  then  the  other,  uttering  a  low,  whistling  note,  and, 
like  the  domestic  cock,  seems  to  be  picking  up  something 
from  the  ground,  until  at  last  the  female  goes  gently 
toward  him."  Capt.  Stokes  has  described  the  habits  and 
'* play-houses"  of  another  species,  the  great  bower-bird, 
wliicli  was  seen  '' amusing  itself  by  flying  backward  and 
forward,  taking  a  shell  alternately  from  each  side  and 
carrying  it  through  the  archway  in  its  mouth."  These 
curious  structures,  formed  solely  as  halls  of  assemblage, 
where  both  sexes  amuse  themselves  and  pay  their  court, 
must  cost  the  birds  much  labor.  The  bower,  for  instance, 
of  the  fawn-breasted  species  is  nearly  four  feet  in  length, 
eighteen  inches  in  height,  and  is  raised  on  a  thick  platform 
of  sticks. 

Decoration. — I  will  first  discuss  the  cases  in  which  the 
males  are  ornamented  either  exclusively  or  in  a  much 
higher  degree  than  the  females,  and  in  a  succeeding 
chapter  those  in  which  both  sexes  are  equally  ornamented, 
and  finally  the  rare  cases  in  which  the  female  is  somewhat 
more  brightly  colored  than  the  male.  As  with  the  artificial 
ornaments  used  by  savage  and  civilized  men  so  with  the  nat- 
ural ornaments  of  birds,  the  head  is  tlie  chief  seat  of 
decoration.*  The  ornaments,  as  mentioned  at  the  com- 
mencement of  this  chapter,  are  wonderfully  diversified.  Tiie 
plumes  on  the  front  or  back  of  the  head  consist  of  variously- 
shaped  feathers,  sometimes  capable  of  erection  or  expan- 
sion, by  which  their  beautiful  colors  are  fully  displayed. 
Elegant  ear -tufts  (see  fig.  39,  ante)  are  occasionally 
present.  The  head  is  sometimes  covered  with  velvety 
down,  as  with  the  pheasant ;  or  is  naked  and  vividly 
colored.  The  throat,  also,  is  sometimes  )rnamented  with 
a  beard,  wattles  or  caruncles.  Such  appendages  are  gen- 
erally brightly  colored  and  no  doubt  serve  as  ornaments, 
though  not  always  ornamental  in  our  eyes;  for  while  the 
male  is  in  the  act  of  courting  the  female  they  often  swell 
and  assume  vivid  tints,  as  in  the  male  turkey.  At  such 
times  the  fleshy  appendages  about  the  head  of  tlie  male 
Tragopan  pheasant  ( Ceriornis  Temminckii)  swell  into  a  large 

*See  remarks  to  this  eifect,  on  the  "Feeling  of  Beauty  Among 
Animals,"  by  Mr.  J.   Shaw,  in  the  "Athenaeum,"  Nov.  24,  1866,  p. 


BIRDS.  435 

lappet  on  the  throat  and  into  two  horns,  one  on  each  side 
of  the  splendid  top-knot;  and  these  are  then  colored  of  the 
most  intense  blue  which  I  have  ever  beheld.  *  The  African 
hornbill  {Bucorax  abyssinicus)  inflates  the  scarlet  bladder- 
like wattle  on  its  neck,  and  with  its  wings  drooping  and 
tail  expanded  "makes  quite  a  grand  appearance/ "f  Even 
the  iris  of  the  eye  is  sometimes  more  brightly  colored  in 
the  male  than  in  the  female;  and  this  is  frequently  the 
case  with  the  beak,  for  instance,  in  our  common  blackbird. 
In  Buceros  corrugatiis  the  whole  beak  and  immense  casque 
are  colored  more  conspicuously  in  the  male  than  in  the 
female;  and  '^  the  oblique  grooves  upon  the  sides  of  the 
lower  mandible  are  peculiar  to  the  male  sex.^^| 

The  head,  again,  often  supports  fleshy  appendages,  fila- 
ments, and  solid  protuberances.  These,  if  not  common  to 
both  sexes,  are  always  confined  to  the  males.  The  solid 
protuberances  have  been  described  in  detail  by  Dr.  W. 
Marshall,  §  who  shows  that  they  are  formed  either  of  can- 
cellated bone  coated  with  skin,  or  of  dermal  and  other 
tissues.  With  mammals  true  horns  are  always  supported 
on  the  frontal  bones,  but  with  birds  various  bones  have 
been  modified  for  this  purpose;  and  in  species  of  the  same 
group  the  protuberances  may  have  cores  of  bone,  or  be 
quite  destitute  of  them,  with  intermediate  gradations  con- 
necting these  two  extremes.  Hence,  as  Dr.  Marshall 
justly  remarks,  variations  of  the  most  different  kinds  have 
served  for  the  development  through  sexual  selection  of 
these  ornamental  appendages.  Elongated  feathers  or 
plumes  spring  from  almost  every  part  of  the  body.  The 
feathers  on  the  throat  and  breast  are  sometimes  developed 
into  beautiful  ruffs  and  collars.  The  tail-feathers  are  fre- 
quently increased  in  length;  as  we  see  in  the  tail-coverts  of 
the  peacock,  and  in  the  tail  itself  of  the  Argus  pheasant. 
With  the  peacock  even  the  bones  of  the  tail  have  been 
modified  to  support  the  heavy  tail-coverts.  ||     The  body  of 

*See  Dr.  Marie's  account  with  colored  figures  in  **Proc.  Zoolog. 
Soc.,"1872,  p.  730. 

fMr.  Monteiro,  "Ibis,"  vol.  iv.,  1862,  p.  339. 

X  "  Land  and  Water,"  1868,  p.  217. 

§  "  Ueber  die  ScLadelbocker,"  etc.,  "  Niederlfindischen  Archiv. 
fur  Zoologie,"  B.  I.,  Heft.  2,  1872. 

I  Dr.  W.  Marshall,  "  Ueber  den  Vogelschwanz,"  ibid,  B.  I.,  Heft, 
2,  1872. 


436  THE  DESCENT  OF  MAN. 

tlie  Argiis  is  not  larger  than  that  of  a  fowl;  yet  the  length 
from  the  end  of  the  beak  to  the  extremity  of  the  tail  is  no 
less  than  five  feet  three  inches,*  and  that  of  the  beauti- 
fully ocellated  secondary  wing- feathers  nearly  three  feet. 
In  a  small  African  night- jar  {Oosmetornis  vexillarius)  one 
of  the  primary  wing-feathers,  during  the  breeding-season, 
attains  a  length  of  twenty-six  inches,  while  the  bird  itself 
is  only  ten  inches  in  length.  In  another  closely  allied 
genus  of  night-jars,  the  shafts  of  the  elongated  wing- 
feathers  are  naked,  except  at  the  extremity,  where  there  is 
a  disk,  f  Again,  in  another  genus  of  night-jars,  the  tail- 
feathers  are  even  still  more  prodigiously  developed.  In 
general  the  feathers  of  the  tail  are  more  often  elongated 
than  those  of  the  wings,  as  any  great  elongation  of  the 
latter  impedes  flight.  We  thus  see  that  in  closely-allied 
birds  ornaments  of  the  same  kind  have  been  gained 
by  the  males  through  the  development  of  widely  different 
feathers. 

It  is  a  curious  fact  that  the  feathers  of  species  belonging 
to  very  distinct  groups  have  been  modified  in  almost 
exactly  the  same  peculiar  manner.  Thus  the  wing-feathers 
in  one  of  the  above-mentioned  night-jars  are  bare  along  the 
shaft,  and  terminate  in  a  disk ;  or  are,  as  they  are  sometimes 
called,  spoon  or  racket  shaped.  Feathers  of  this  kind  occur 
in  the  tail  of  a  motmot  {Eumomota  superciliaris),  of  a  king- 
fisher, finch,  humming-bird,  parrot,  several  Indian  drongos 
(Dicrurus  and  Edolius,  in  one  of  which  the  disk  stands 
vertically),  and  in  the  tail  of  certain  birds  of  paradise. 
In  these  latter  birds,  similar  feathers,  beautifully  ocellated, 
ornament  the  head,  as  is  likewise  the  case  with  some  galli- 
naceous birds.  In  an  Indian  bustard  (^Syiolieotides  auritus) 
the  feathers  forming  the  ear-tufts,  which  are  about  four 
inches  in  length,  also  terminate  in  disks.  |  It  is  a  most 
singular  fact  that  the  motmots,  as  Mr.  Salvin  has  clearly 
shown,  §  give  to  their  tail-feathers  the  racket-shape  by 
biting  oft  the  barbs,  and,  further,  that  this  continued 
mutilation  has  produced  a  certain  amount  of  inherited 
effect. 

*  Jardine's  "Naturalist  Library;  Birds,"  vol,  xiv,  p.  166. 
f  Sclater,  in  tlie  "  Ibis,"  vol.  vi,  1864,  p.  114.     Livingstone,  "Expe- 
dition to  the  Zambesi,"  1865,  p.  66. 

JJerdon,  "Birds  of  India,"  vol.  iii,  p.  620. 
§  "Proc.  Zoolog.  Soc,"  1873,  p.  439. 


BIRDS. 


m 


Again,  the  barbs  of  the  feathers  in  various  widely-distinct 
birds  are  filamentous  or  plumose,  as  with  some  herons. 


Fig.  47.    Paradisea  Papuaiia  (T.  W.  Wood), 


ibises,  birds  of  paradise,  and  Gallinaceae.    In  other  cases  the 
barbs  disappear,  leaving  the  shafts  bare  from  end  to  end; 


438  THE  DESCENT  OF  MAN. 

and  these  in  the  tail  of  the  Paradisea  apoda  attain  a 
length  of  thirty-four  inches;*  in  P.  Papiiana  (fig.  47) 
they  are  much  shorter  and  thin.  Smaller  feathers  when 
thus  denuded  appear  like  bristles,  as  on  the  breast  of  the 
turkey-cock.  As  any  fleeting  fashion  in  dress  comes  to  be 
admired  by  man,  so  with  birds  a  change  of  almost  any 
kind  in  the  structure  or  coloring  of  the  feathers  in  the 
male  appears  to  have  been  admired  by  the  female.  The 
fact  of  the  feathers  in  widely  distinct  groups  having 
been  modified  in  an  anologous  manner  no  doubt 
depends  primarily  on  all  the  feathers  having  nearly 
the  same  structure  and  manner  of  development,  and 
consequently  tending  to  vary  in  the  same  manner.  We 
often  see  a  tendency  to  analogous  variability  in  the 
plumage  of  our  domestic  breeds  belonging  to  dis- 
tinct species.  Thus  top-knots  have  appeared  in  several 
species.  In  an  extinct  variety  of  the  turkey  the  top-knot 
consisted  of  bare  quills  surmounted  with  plumes  of  down, 
so  that  they  somewhat  resembled  the  racket-shaped  feathers 
above  described.  In  certain  breeds  of  the  pigeon  and  fowl  the 
feathers  are  plumose,  with  some  tendency  in  the  shafts  to 
be  naked.  In  the  Sebastopol  goose  the  scapular  feathers 
are  greatly  elongated,  curled,  or  even  spirally  twisted,  with 
the  margins  plumose,  f 

In  regard  to  color,  hardly  anything  need  here  be  said, 
for  every  one  knows  how  splendid  are  the  tints  of  many 
birds  and  how  harmoniously  they  are  combined.  The 
colors  are  often  metallic  and  iridescent.  Circular  spots 
are  sometimes  surrounded  by  one  or  more  differently 
shaded  zones  and  are  thus  converted  into  ocelli.  Nor  need 
much  be  said  on  the  wonderful  difference  between  the 
sexes  of  many  birds.  The  common  peacock  offers  a  strik- 
ing instance.  Female  birds  of  paradise  are  obscurely  col- 
ored and  destitute  of  all  ornaments,  while  the  males  are 
probably  the  most  highly  decorated  of  all  birds,  and  in  so 
many  different  ways  that  they  must  be  seen  to  be  appre 
ciated.  The  elongated  and  golden-orange  plumes  which 
spring  from  beneath  the  wings  of  the  Paradisea  apoda 
when  vertically  erected  and  made  to  vibrate  are  described 

*  Wallace,  in  "Annals  and  Mag  of  Nat.  Hist.,"  vol.  xx,  1857,  p. 
416,  and  in  his  "  Malay  Archipelago,"  vol.  ii,  1869,  p.  390. 

f  See  my  work  on  "The  Variation  of  Animals  and  Plants  under 
Domestication,"  vol.  i,  pp.  289,  293. 


BIRDS. 


439 


as  forming  a  sort  of  halo,  in  the  center  of  which  the  head 
*^  looks  like  a  little  emerald  sun  with  its  rays  formed  by 


Fig.  48.    Lophornis  ornatus,  male  and  female  (from  Brehm). 

the  two  plumes."*  In  another  most  beautiful  species  the 
head  is  bald  "and  of  a  rich  cobalt  blue,  crossed  by  several 
lines  of  black  velvety  feathers,  "f 

*Qiioted  from  M.  de  Lafresnaye  ia  "  Annals  and  Mag.  of  Nat. 
Hist.,"  vol.  xiii,  1854,  p.  157:  see  also  Mr.  Wallace's  much  fuller 
account  in  vol.  xx,  1857,  p.  412.  and  in  his  "Malay  Archipelago." 

f  Wallace,  "  The  Malay  Archipelago,"  vol.  ii,  1869,  p.  405. 


440 


THE  DESCENT  OF  MAN. 


Male  humming-birds  (figs.   48  and  49)  almost  vie  with 
birds  of  paradise  in  their  beauty,  as  every  one  will  admit 


Fifj.  49.    Spathura  underwoodi,  male  and  female  (from  Brehm). 

who  has  seen  Mr.  Gould's  splendid  volumes  or  his  rich  col- 
lection.    It  is  very  remarkable  in  how  many  different  ways 


BIRDS.  441 

these  birds  are  ornamented.  Almost  every  part  of  their 
plumage  has  been  taken  advantage  of  and  modified;  and 
the  modifications  have  been  carried,  as  Mr.  Gould  showed 
me,  to  a  wonderful  extreme  in  some  species  belonging  to 
nearly  every  sub-group.  Such  cases  are  curiously  like 
those  which  we  see  in  our  fancy  breeds,  reared  by  man  for 
the  sake  of  ornament;  certain  individuals  originally  varied 
in  one  character,  and  other  individuals  of  the  same  species 
in  other  characters;  and  these  have  been  seized  on  by  man 
and  much  augmented,  as  shown  by  the  tail  of  the  fantail- 
pigeon,  the  hood  of  the  jacobin,  the  beak  and  wattle  of 
the  carrier,  and  so  forth.  The  sole  difference  between  these 
cases  is  that  in  the  one  the  result  is  due  to  man^s  selection, 
while  in  the  other,  as  with  humming-birds,  birds  of  para- 
dise, etc.,  it  is  due  to  the  selection  by  the  females  of  the 
more  beautiful  males. 

I  will  mention  only  one  other  bird,  remarkable  from  the 
extreme  contrast  in  color  between  the  sexes,  namely,  the 
famous  bell-bird  {Chasmorhynclius  oiiveus)  of  South 
America,  the  note  of  which  can  be  distinguished  at  the 
distance  of  nearly  three  miles,  and  astonishes  every  one 
when  first  hearing  it.  The  male  is  pure  white,  while  the 
female  is  dusky-green;  and  white  is  a  very  rare  color  in  ter- 
restrial species  of  moderate  size  and  inoffensive  habits. 
The  male,  also,  as  described  by  Waterton,  has  a  spiral  tube 
nearly  three  inches  in  length,  which  rises  from  the  base  of 
the  beak.  It  is  jet-black,  dotted  over  with  minute  downy 
feathers.  This  tube  can  be  inflated  with  air,  through  a 
communication  with  the  palate  ;  and  when  not  inflated 
hangs  down  on  one  side.  The  genus  consists  of  four  species, 
the  males  of  which  are  very  distinct,  while  the  females,  as 
described  by  Mr.  Sclater  in  a  very  interesting  paper,  closely 
resemble  each  other,  thus  offering  an  excellent  instance  of 
the  common  rule  that  within  the  same  group  the  males 
differ  much  more  from  each  other  than  do  the  females.  In 
a  second  species  {C.  nudicollis)  the  male  is  likewise  snow- 
white,  with  the  exception  of  a  large  space  of  naked  skin 
on  the  throat  and  round  the  eyes,  which  during  the  breed- 
ing-season is  of  a  fine  green  color.  In  the  third  species 
{C.  tricar unculatus)  the  head  ai\d  neck  alone  of  the  male 
are  white,  the  rest  of  the  body  being  chestnut-brown,  and 
the  male  of  this  species  is  provided  with  three  filamentous 
projections  half  as  long  as  the  body,  one  rising  from  the 


442  THE  DESCENT  OF  MAN. 

base  of  the  beak  and  the  two  others  from  the  corners  of  the 
month.* 

l^he  colored  phimage  and  certain  other  ornaments  of  the 
adult  males  are  either  retained  for  life  or  are  periodically 
renewed  during  the  summer  and  breeding-season.  At  this 
same  season  the  beak  and  naked  skin  about  the  head  fre- 
quently change  color,  as  with  some  herons,  ibises,  gulls, 
one  of  the  bell-birds  just  noticed,  etc.  In  the  white  ibis, 
the  cheeks,  the  inflatable  skin  of  the  throat,  and  the  basal 
portion  of  the  beak  then  become  crimson,  f  In  one  of  the 
rails,  Gallicrex  cristatus^  a  large  red  caruncle  is  developed 
during  this  period  on  the  head  of  the  male.  So  it  is  with 
a  thin  horny  crest  on  the  beak  of  one  of  the  pelicans,  P. 
erythrorhynchus;  for,  after  the  breeding-season,  these  horny 
crests  are  shed,  like  horns  from  the  heads  of  stags,  and  the 
shore  of  an  island  in  a  lake  in  Nevada  was  foumd  covered 
with  these  curious  exuviae.  J 

Changes  of  color  in  the  plumage  according  to  the  season 
depend,  firstly  on  a  double  annual  moult,  secondly  on  an 
actual  change  of  color  in  the  feathers  themselves,  and 
thirdly  on  their  dull-colored  margins  being  periodically 
shed,  or  on  these  three  processes  more  or  less  combined. 
The  shedding  of  the  deciduary  margins  may  be  compared 
with  the  shedding  of  their  down  by  very  young  birds;  for 
the  down  in  most  cases  arises  from  the  summits  of  the  first 
true  feathers.  § 

With  respect  to  the  birds  which  annually  undergo  a 
double  moult,  there  are,  firstly,  some  kinds,  for  instance 
snipes,  swallow-plovers  (Glareolae),  and  curlews,  in  which 
the  two  sexes  resemble  each  other  and  do  not  change  color 
at  any  season.  I  do  not  know  whether  the  winter  plumage 
is  thicker  and  warmer  than  the  summer  plumage,  but 
warmth  seems  the  most  probable  end  attained  of  a  double 
moult,  where  there  is  no  change  of  color.  Secondly,  there 
are  birds,  for  instance,  certain  species  of  Totanus  and  other 

*Mr.  Sclater,  "  Intellectual  Observer,"  Jan.,  1867.  "  Waterton's 
Wanderings,"  p.  118.  See  also  Mr.  Salvin's  interesting  paper,  with 
a  plate,  in  the  "  Ibis,"  1865,  p.  90. 

t  "  Land  and  Water,"  1867,  p.  394. 

tMr.  D.  G.  Elliot,  in  '•  Proc,  Zool.  Soc,"  1869,  p.  589. 

^  Nitzsch's  "  Pterylography,"  edited  by  P.  L.  Sclater.  Ray  Soc, 
1867,  p.  14. 


BIRDS.  443 

Grallatores,  the  sexes  of  which  resemble  each  other,  but  in 
which  the  summer  and  winter  plumage  differ  slightly  in 
color.  The  difference,  however,  in  these  cases  is  so  small 
that  it  can  hardly  be  an  advantage  to  them;  and  it  may, 
perhaps,  be  attributed  to  the  direct  action  of  the  different 
conditions  to  which  the  birds  are  exposed  during  the  two 
seasons.  Thirdly,  there  are  many  other  birds  the  sexes  of 
which  are  alike,  but  which  are  widely  different  in  their 
summer  and  winter  plumage.  Fourthly,  there  are  birds 
the  sexes  of  which  differ  from  each  other  in  color;  but  the 
females,  though  moulting  twice,  retain  the  same  colors 
throughout  the  year,  while  the  males  undergo  a  change  of 
color,  sometimes  a  great  one,  as  with  certain  bustards. 
Fifthly  and  lastly,  there  are  birds  the  sexes  of  which  differ 
from  each  other  in  both  their  summer  and  winter  plumage; 
but  the  male  undergoes  a  greater  amount  of  change  at  each 
recurrent  season  than  the  female — of  which  the  ruff  {Ma- 
chetes pugnax)  offers  a  good  instance. 

With  respect  to  the  cause  or  purpose  of  the  differences 
in  color  between  the  summer  and  winter  plumage,  this  may 
in  some  instances,  as  with  the  ptarmigan,*  serve  during 
both  seasons  as  a  protection.  When  the  difference  between 
the  two  plumages  is  slight  it  may  perhaps  be  attributed,  as 
already  remarked,  to  the  direct  action  of  the  conditions  of 
life.  But  with  many  birds  there  can  hardly  be  a  doubt 
that  the  summer  plumage  is  ornamental,  even  when  both 
sexes  are  alike.  We  may  conclude  that  this  is  the  case  with 
many  herons,  egrets,  etc.,  for  they  acquire  their  beautiful 
plumes  only  during  the  breeding-season.  Moreover,  such 
plumes,  top-knots,  etc.,  though  possessed  by  both  sexes, 
are  occasionally  a  little  more  developed  in  the  male  than  in 
the  female;  and  they  resemble  the  plumes  and  ornaments 
possessed  by  the  males  alone  of  other  birds.  It  is  also  known 
that  confinement,  by  affecting  the  reproductive  system  of 
male  birds,  frequently  checks  the  development  of  their 
secondary  sexual  characters,  but  has  no  immediate  influence 
on  any  other  characters;  and  I  am  informed  by  Mr.  Bart- 

*  The  brown  mottled  summer  plumage  of  the  ptarmigan  is  of  as 
much  importance  to  it,  as  a  protection,  as  the  white  winter  plumage; 
for  in  Scandinavia  during  the  spring,  when  the  snow  has  disap- 
peared, this  bird  is  known  to  suffer  greatly  from  birds  of  prey,  before 
it  has  acquired  its  summer  dress;  see  Wilhelm  von  Wright,  in. 
Lloyd,  "  Game  Birds  of  Sweden,"  1867,  p.  125. 


444  M"^  DESCENT  OF  MAN. 

lett  that  eight  or  nine  specimens  of  the  Knot  (Tringa 
camttus)  retained  their  unadorned  winter  plumage  in  the 
Zoological  Gardens  throughout  the  year^  from  which  fact 
we  may  infer  that  the  summer  plumage,  though  common 
to  both  sexes,  partakes  of  the  nature  of  the  exclusively 
masculine  plumage  of  many  other  birds.* 

From  the  foregoing  facts,  more  especially  from  neither 
sex  of  certain  birds  changing  color  during  either  annual 
moult,  or  changing  so  slightly  that  the  change  can  hardly 
be  of  any  service  to  them,  and  from  the  females  of  other 
species  moulting  twice  yet  retaining  the  same  color  through- 
out the  year,  we  may  conclude  that  the  habit  of  annually 
moulting  twice  has  not  been  acquired  in  order  that  the 
male  should  assume  an  ornamental  character  during  the 
breeding-season;  but  that  the  double  moult,  having  been 
originally  acquired  for  some  distinct  purpose,  has  subse- 
quently been  taken  advantage  of  in  certain  cases  for  gaining 
a  nuptial  plumage. 

It  appears  at  first  sight  a  surprising  circumstance  that 
some  closely-allied  species  should  regularly  undergo  a 
double  annual  moult,  and  others  only  a  single  one.  The 
ptarmigan,  for  instance,  moults  twice  or  even  thrice  in  the 
year,  and  the  black-cock  only  once;  some  of  the  splen- 
didly colored  honey-suckers  (Nectariniae)  of  India  and 
some  sub-genera  of  obscurely  colored  pipits  (Anthus)  have 
a  double,  while  others  have  only  a  single  annual  moult.  \ 
But  the  gradations  in  the  manner  of  moulting,  which 
are  known  to  occur  with  various  birds,  show  us 
how  species  or  whole  groups  might  have  originally 
acquired  their  double  annual  moult,  or  having  once 
gained  the  habit,  have  again  lost  it.  With  certain  bus- 
tards and  plovers  the  vernal  moult  is  far  from  complete, 
some  feathers  being  renewed,  and  some  changed  in 
color.     There  is  also  reason  to  believe  that  with    certain 

*  In  regard  to  the  previous  statements  on  moulting,  see,  on  snipes, 
etc.,  Macgilliv^ray,  "Hist.  Brit.  Birds,"  vol.  iv,  p.  371;  on  Glareolae, 
curlews  and  bustards,  Jerdon,  "Birds  of  India,"  vol.  iii,  pp.  615, 
630,  683;  on  Totanus,  ibid,  p.  700;  on  the  plumes  of  herons,  ibid,  p. 
738,  and  Macgillivray,  vol.  iv,  pp.  435,  444,  and  Mr.  Stafford  Allen, 
in  the  "Ibis,"  vol.  v,  1863,  p.  33. 

f  On  the  moulting  of  the  ptarmigan,  see  Gould's  "  Birds  of  Great 
Britain."  On  the  honey-suckers,  Jerdon,  "Birds  of  India,"  vol.  i, 
pp.  359,  365,  369.  On  the  moulting  of  Anthus,  see  Blyth,  in  "  Ibis," 
1867,  p.  32. 


BIRDS.  445 

bustards  and  rail-like  birds,  which  properly  undergo  a 
double  moult,  some  of  the  older  males  retain  their  nuptial 
plumage  throughout  the  year.  A  few  highly  modified 
feathers  may  merely  be  added  during  the  spring  to  the 
plumage,  as  occurs  with  the  disk-formed  tail-feathei*s  of 
certain  drongos  (Bhringa)  in  India,  and  with  the  elon- 
gated feathers  on  the  back,  neck,  and  crest  of  certain 
herons.  By  such  steps  as  these,  the  vernal  moult  might 
be  rendered  more  and  more  complete,  until  a  perfect 
double  moult  was  acquired.  Some  of  the  birds  of  paradise 
retain  their  nuptial  feathers  throughout  the  year,  and  thus 
have  only  a  single  moult ;  others  cast  them  directly  after 
the  breeding-season,  and  thus  have  a  double  moult;  and 
others  again  cast  them  at  this  season  during  the  first  year, 
but  not  afterward;  so  that  these  latter  species  are  interme- 
diate in  their  manner  of  moulting.  There  is  also  a  great 
difference  with  many  birds  in  the  length  of  time  during 
which  the  two  annual  plumages  are  retained;  so  that  one 
might  come  to  be  retained  for  the  whole  year,  and 
the  other  completely  lost.  Thus  in  the  spring  Machetes 
pugnax  retains  his  ruff  for  barely  two  months.  In 
Natal  the  male  widow-bird  (Ohera  progne)  acquires  his 
fine  plumage  and  long  tail-feathers  in  December  or  Janu- 
ary, and  loses  them  in  March  ;  so  that  they  are  retained 
only  for  about  three  months.  Most  species,  which  undergo 
a  double  moult,  keep  their  ornamental  feathers  for  about 
six  months.  The  male,  however,  of  the  wild  Gallus  ban- 
kiva  retains  his  neck-hackles  for  nine  or  ten  months;  and 
when  these  are  cast  off  the  underlying  black  feathers  on 
the  neck  are  fully  exposed  to  view.  But  with  the  domesti- 
cated descendant  of  this  species  the  neck-hackles  of  the 
male  are  immediately  replaced  by  new  ones ;  so  that  we 
here  see,  as  to  part  of  the  plumage,  a  double  moult  changed 
under  domestication  into  a  single  moult.* 

*  For  tbe  foregoing  statements  in  regard  to  partial  moults,  and  on 
old  males  retaining  their  nuptial  plumage,  see  Jerdon,  on  bustards 
and  plovers,  in  "Birds  of  India,"  vol.  iii,  pp.  617,  637,  709,  711. 
Also  BIyth  in  "  Land  and  Water,"  1867,  p.  84.  On  the  moulting  of 
Paradisea,  see  an  interesting  article  by  Dr.  W.  Marshall,  "  Archives 
Neerlandaises,"  tom.  vi,  1871.  On  the  Vidua,  "Ibis,"  vol.  iii,  1861, 
p.  133.  On  the  Drongo  shrikes,  Jerdon,  ibid,  vol.  i,  p.  435.  On  the 
vernal  moult  of  the  Herodias  bubulcus,  Mr.  S.  S.  Allen,  in  "Ibis," 
1863,  p.  33.  On  Gallus  hankiva,  Blyth,  in  "  Annals  and  Mag.  of 
Nat.  Hist.,"  vol.  i,  1848,  p.  455;  see  also  on  this  subject,  m^  "Vari- 
ation of  Animals  nnder  Domestication,"  vol.  i,  p.  236. 


446  THE  DESCENT  OF  MAN. 

The  common  drake  {Anas  hoschas)  after  the  breeding- 
season,  is  well  known  to  lose  his  male  plumage  for  a 
period  of  three  months,  during  which  time  he  assumes 
that  of  the  female.  The  male  pin-tail  duck  {Anas  acuta) 
loses  his  plumage  for  the  shorter  period  of  six  weeks  or 
two  months  ;  and  Montagu  remarks  that  ^^  this  double 
moult  within  so  short  a  time  is  a  most  extraordinary  cir- 
cumstance that  seems  to  bid  defiance  to  all  human  reason- 
ing." But  the  believer  in  the  gradual  modification  of 
species  will  be  far  from  feeling  surprise  at  finding  grada- 
tions of  all  kinds.  If  the  male  pin-tail  were  to  acquire  his 
new  plumage  within  a  still  shorter  period  the  new  male 
feathers  would  almost  necessarily  be  mingled  with  the  old, 
and  both  with  some  proper  to  the  female;  and  this  appar- 
ently is  the  case  with  the  male  of  a  not  distantly  allied 
bird,  namely,  the  Merganser  serrator,  for  the  males  are 
said  to  ^^  undergo  a  change  of  plumage  which  assimilates 
them  in  some  measure  to  the  female.''  By  a  little  further 
acceleration  in  the  process  the  double  moult  would  be  com- 
pletely lost.* 

Some  male  birds,  as  before  stated,  become  more  brightly 
colored  in  the  spring,  not  by  a  vernal  moult,  but  either  by 
an  actual  change  of  color  in  the  feathers  or  by  their 
obscurely  colored  deciduary  margins  being  shed.  Changes 
of  color  thus  caused  may  last  for  a  longer  or  shorter  time. 
In  the  Pelecanus  onocrotalus  a  beautiful  rosy  tint  with 
lemon-colored  marks  on  the  breast  overspreads  the  whole 
plumage  in  the  spring;  but  these  tints,  as  Mr.  Sclater 
states,  ^'do  not  last  long,  disappearing  generally  in  about 
six  weeks  or  two  months  after  they  have  been  attained." 
Certain  finches  shed  the  margins  of  their  feathers  in  the 
spring  and  then  become  brighter  colored,  while  other 
finches  undergo  no  such  change.  Thus  the  Fringilla 
tristis  of  the  United  States  (as  well  as  many  other  Ameri- 
can species)  exhibits  its  bright  colors  only  when  the  winter 
is  past,  while  our  goldfinch,  which  exactly  represents  this 
bird  in  habits,  and  our  siskin  which  represents  it  still  more 
closely  in  structure,  undergo  no  such  annual  change.  But 
a  difference  of  this  kind  in  the  plumage  of   allied  species 

*See  Macgillivray,  "Hist.  British  Birds," (vol.  v,  pp.  34,  70,  223) 
on  the  moulting  of  the  Anatidae,  with  quotations  from  Waterton  and 
Montagu,    Also  Yarrellj  "  Hist,  of  British  Birds,"  vol.  iii,  p.  243. 


BIRDS.  447 

is  not  surprising,  for  with  the  common  linnet,  which 
belongs  to  the  same  family,  the  crimson  forehead  and 
breast  are  displayed  only  during  the  summer  in  England, 
while  in  Madeira  these  colors  are  retained  throughout  the 
year.  * 

Display  by  Male  Birds  of  Their  Plumage. — Ornaments 
of  all  kinds,  whether  permanently  or  temporarily  gained, 
are  sedulously  displayed  by  the  males,  and  apparently  serve 
to  excite,  attract  or  fascinate  the  females.  But  the  males 
will  sometimes  display  their  ornaments  when  not  in  the 
presence  of  the  females,  as  occasionally  occurs  with  grouse 
at  their  balz-places,  and  as  may  be  noticed  with  the 
peacock;  this  latter  bird,  however,  evidently  wishes  for  a 
spectator  of  some  kind,  and,  as  I  have  often  seen,  will  show 
off  his  finery  before  poultry,  or  even  pigs,  f  All  naturalists 
who  have  closely  attended  to  the  habits  of  birds,  whether 
in  a  state  of  nature  or  under  confinement,  are  unani- 
mously of  opinion  that  the  males  take  delight  in  displaying 
their  beauty.  Audubon  frequently  speaks  of  the  male  as 
endeavoring  in  various  ways  to  charm  the  female.  Mr. 
Gould,  after  describing  some  peculiarities  in  a  male 
humming-bird,  says  he  has  no  doubt  that  it  has  the  power 
of  displaying  them  to  the  greatest  advantage  before  the 
female.  Dr.  JerdonJ  insists  that  the  beautiful  plumage  of 
the  male  serves  '^'^  to  fascinate  and  attract  the  female."' 
Mr.  Bartlett,  at  the  Zoological  Gardens,  expressed  himself 
to  me  in  the  strongest  terms  to  the  same  effect. 

It  must  be  a  grand  siglit  in  the  forests  of  India  ^'  to  come 
suddenly  on  twenty  or  thirty  pea-fowl,  the  males  displaying 
their  gorgeous  trains,  and  strutting  about  in  all  the  pomp 
of  pride  before  the  gratified  females."  The  wild  turkey-cock 
erects  his  glittering  plumage,  expands  his  finely-zoned  tail 
and  barred  wing-feathers,  and  altogether,  with  his  crimson 

*0n  the  pelican,  see  Sclater,  in  " Proc.  Zool.  Soc,"  1868,  p.  265. 
On  the  American  finches,  see  Audubon,  "  Ornitb.  Biograpby,"  vol.  i, 
pp.  174,  221,  and  Jerdon,  "  Birds  of  India,"  vol.  ii,  p.  383.  On  tbe 
FringUla  eannabina  of  Madeira,  Mr.  E.  Vernon  Harcourt,  "  Ibis," 
vol.  V,  1863,  p.  230. 

f  See  also  "  Ornamental  Poultry,"  by  Rev.  E.  S.  Dixen,  1848,  p.  8. 

t*' Birds  of  India,"  introduct.,  vol,  i,  p.  24,  on  the  peacock,  vol. 
iii,  p.  507.  See  Gould's  "  Introduction  to  the  Trochilidae,"  1861,  pp. 
15,111. 


448 


THE  DESCENT  OF  MAN. 


and  blue  wattles,  makes  a  superb,  though,  to  our  eyes, 
grotesque  appearance.  Similar  facts  have  already  been 
given  with  respect  to  grouse  of  various  kinds.  Turning  to 
another  order.  The  male  Rupicola  crocea  (fig.  50)  is  one 
of  the  most  beautiful  birds  in  the  world,  being  of  a  splendid 
orange,  with  some  of  the  feathers  curiously  truncated  and 


Fig.  50.    Rupicola  crocea,  male  (T.  W.  Wood). 


plumose.  The  female  is  brownish -green,  shaded  with  red, 
and  has  a  much  smaller  crest.  Sir  R.  Schomburgk  has 
described  their  courtship;  he  found  one  of  their  meeting- 
places  where  ten  males  and  two  females  were  present.  Tlie 
space  was  from  four  to  five  feet  in  diameter,  and  appeared 
to  have  been  cleared  of  every  blade  of  grass  and  smoothed 
as  if   by  human   hands.     A  male  ''was  capering  to  tl^e 


BIRDS.  449 

apparent  delight  of  several  others.  IS'ow  spreading  its 
wings,  throwing  up  its  head,  or  opening  its  tail  like  a  fan; 
now  strutting  about  with  a  hopping  gait  until  tired,  when 
it  gabbled  some  kind  of  note,  and  was  relieved  by  another. 
Thus  three  of  them  successively  took  the  field,  and  then, 
with  self-approbation,  withdrew  to  rest."  The  Indians,  in 
order  to  obtain  their  skins,  wait  at  one  of  the  meeting- 
places  till  the  birds  are  eagerly  engaged  in  dancing,  and 
then  are  able  to  kill  with  their  poisoned  arrows  four  or  five 
males,  one  after  the  other.  *  With  birds  of  paradise  a  dozen 
or  more  full-plumaged  males  congregate  in  a  tree  to  hold  a 
dancing-party,  as  it  is  called  by  the  natives;  and  here  they 
fly  about,  raise  their  wings,  elevate  their  exquisite  plumes, 
at  id  make  them  vibrate,  and  the  whole  tree  seems,  as  Mr. 
Wallace  remarks,  to  be  filled  with  waving  plumes.  When 
thus  engaged  they  become  so  absorbed  that  a  skillful  archer 
may  shoot  nearly  the  whole  party.  These  birds,  when  kept 
in  confinement  in  the  Malay  Archipelago,  are  said  to  take 
much  care  in  keeping  their  feathers  clean;  often  spreading 
them  out,  examining  them,  and  removing  every  speck  of 
dirt.  One  observer,  who  kept  several  pairs  alive,  did  not 
doubt  that  the  display  of  the  male  was  intended  to  please 
the  female,  t 

The  gold  and  Amherst  pheasants  during  their  courtship 
not  only  expand  and  raise  their  splendid  frills  but  twist 
them,  as  I  have  myself  seen,  obliquely  toward  the  female 
on  whichever  side  she  may  be  standing,  obviously  in  order 
that  a  large  surface  may  be  displayed  before  her.  J  They 
likewise  turn  their  beautiful  tails  and  tail-coverts  a  little 
toward  the  same  side.  Mr.  Bartlett  has  observed  a  male 
Polyplectron  (fig.  51)  in  the  act  of  courtship,  and  has 
shown  me  a  specimen  stuffed  in  the  attitude  then  assumed. 
The  tail  and  wing  feathers  of  this  bird  are  ornamented 
with   beautiful   ocelli,    like   those  on  the   peacock's  train. 

*  "  Journal  of  R,  Geograph.  Soc."  vol.  x,  1840,  p.  236. 

f  "  Annals  and  Mag.  of  Nat.  Hist.,"  vol.  xiii,  1854,  p.  157;  also 
Wallace,  ibid,  vol.  xx,  1857,  p.  412,  and  "The  Malay  Archipelago," 
vol.  ii,  1869,  p.  252.  Also  Dr.  Bennett,  as  quoted  by  Brehm,  "  Thier- 
leben,"  B.  iii,  s.  826. 

JMr.  T.  W.  Wood  has  given  ("The  Student,"  April,  1870,  p. 
115)  a  full  account  of  this  manner  of  display  by  the  gold  pheasant 
and  by  the  Japanese  pheasant.  Ph.  versicolor;  and  he  calls  it  the 
lateral  or  one-sided  display. 


450  THE  DESCENT  OF  MAN. 

Now  when  the  peacock  displays  himself  he  expands  and 


Fig.  51.    Polyplectron  chinquis,  male  i,T.  W.  Wood). 


erects  his  tail  transversely  to  his  body,  for  he  stands  in 
front  of  the  female,  and  has  to  show  off  at  the  same  time 


BIBBS.  451 

his  rich  blue  throat  and  breast.  But  the  breast  of  the  Poly- 
plectron  is  obscurely  colored,  and  the  ocelli  are  not  con- 
fined to  the  tail-feathers.  Consequently  the  Polyplectron 
does  not  stand  in  front  of  the  female;  but  he  erects  and 
expands  his  tail-feathers  a  little  obliquely,  lowering  the  ex- 
panded wing  on  the  same  side  and  raising  that  on  the 
opposite  side.  In  this  attitude  the  ocelli  over  the  whole 
body  are  exposed  at  the  same  time  before  the  eyes  of  the 
admiring  female  in  one  grand  bespangled  expanse.  To 
whichever  side  she  may  turn  the  expanded  wings  and  the 
obliquely-held  tail  are  turned  toward  her.  The  male  Trag- 
opan  pheasant  acts  in  nearly  the  same  manner,  for  he  raises 
the  feathers  of  the  body,  though  not  the  wing  itself,  on  the 
side  which  is  opposite  to  the  female,  and  which  would 
otherwise  be  concealed,  so  that  nearly  all  the  beautifully 
spotted  feathers  are  exhibited  at  the  same  time. 

The  Argus  pheasant  affords  a  much  more  remarkable 
case.  The  immensely  developed  secondary  wing-feathers 
are  confined  to  the  male;  and  each  is  ornamented  with  a 
row  of  from  twenty  to  twenty-three  ocelli  above  an  inch  in 
diameter.  These  feathers  are  also  elegantly  marked  with 
oblique  stripes  and  rows  of  spots  of  a  dark  color,  like  those 
on  the  skin  of  a  tiger  and  leopard  combined.  These  beau- 
tiful ornaments  are  hidden  until  the  male  shows  himself  off 
before  the  female.  He  then  erects  his  tail  and  expands  his 
wiug-feathers  into  a  great,  almost  upright,  circular  fan  or 
shield,  which  is  carried  in  front  of  the  body.  The  neck 
and  head  are  held  on  one  side,  so  that  they  are  concealed 
by  the  fan;  but  the  bird  in  order  to  see  the  female,  before 
whom  he  is  displaying  himself,  sometimes  pushes  his  head 
between  two  of  the  long  wing-feathers  (as  Mr.  Bartlett  has 
seen),  and  then  presents  a  gi'otesque  appearance.  This 
must  be  a  frequent  habit  with  the  bird  in  a  state  of  nature, 
for  Mr.  Bartlett  and  his  son,  on  examining  some  perfect 
skins  sent  from  the  east,  found  a  place  between  two  of  the 
feathers  which  was  much  frayed,  as  if  the  head  had  here 
frequently  been  pushed  through.  Mr.  Wood  thinks  that 
the  male  can  also  peep  at  the  female  on  one  side  beyond  the 
margin  of  the  fan. 

The  ocelli  on  the  wing-feathers  are  wonderful  objects, 
for  they  are  so  shaded  that,  as  the  Duke  of  Argyll  remarks,* 

*  ''  The  Reign  of  Law,"  1867,  p.  203, 


452  THE  DESCENT  OF  MAN. 

they  stand  out  like  balls  lying  loosely  within  sockets.  When 


Fig.  52.    Side  view  of  male  Argus  pheasant,  while  displaying  before  the 
female.    Observed  and  sketched  from  nature  by  Mr.  T.  W.  Wood. 


I  looked  at  the  specimen  in  the  British  Museum,  which  is 
mounted  with  the  wings  expanded  and  trailing  downward, 


BIRDS,  453 

I  was^  however,  greatly  disappointed,  for  the  ocelli  appeared 
flat,  or  eveu  concave.  Bnt  Mr.  Gould  soon  made  the  case 
clear  to  me,  for  he  held  the  feathers  erect,  in  the  position 
in  which  they  would  naturally  be  displayed,  and  now,  from 
the  light  shining  on  them  from  above,  each  ocellus  at  once 
resembled  the  ornament  called  a  ball  and  socket.  These 
feathers  have  been  shown  to  several  artists,  and  all  have 
expressed  their  admimtion  at  the  perfect  shading.  It  may 
well  be  asked,  could  such  artistically  shaded  ornaments 
have  been  formed  by  means  of  sexual  selection  ?  But  it 
will  be  convenient  to  defer  giving  an  answer  to  this  ques- 
tion until  we  treat  in  the  next  chapter  of  the  principle  of 
gradation. 

The  foregoing  remarks  relate  to  the  secondary  wing- 
feathei*s,  but  the  primary  wing-feathers,  which  in  most 
gallinaceous  birds  are  uniformly  colored,  are  in  the  Argus 
pheasant  equally  wonderful.  They  are  of  a  soft  brown  tint 
with  numerous  dark  spots,  each  of  which  consists  of  two  or 
three  black  dots  with  a  surrounding  dark  zone.  But  the 
chief  ornament  is  a  space  parallel  to  tlie  dark-blue  shaft, 
which  in  outline  forms  a  perfect  second  feather  lying  within 
the  true  feather.  This  inner  pai't  is  colored  of  a  lighter 
chestnut,  and  is  thickly  dotted  with  minute  white  points. 
I  have  shown  this  featiier  to  several  persons^  and  many 
have  admired  it  even  more  than  the  ball  and  socket  feath- 
ers, and  have  declared  that  it  was  more  like  a  work  of  art 
than  of  nature.  Now  these  feathers  are  quite  hidden  on 
all  ordinary  occasions,  but  are  fully  displayed,  together 
with  the  long  secondary  feathers,  when  they  are  all  ex- 
panded together  so  as  to  form  the  great  fan  or  shield. 

The  case  of  the  male  Argus  pheasant  is  eminently  inter- 
esting, because  it  affords  good  evidence  that  the  most  re- 
fined beauty  may  serve  as  a  sexual  charm,  and  for  no  other 
purpose.  We  must  conclude  that  this  is  the  case,  as  the 
secondary  and  primary  wing-feathers  are  not  at  all  dis- 
played, and  the  ball  and  socket  ornaments  are  not  exhibited 
in  full  perfection  until  the  male  assumes  the  attitude  of 
coui-tship.  The  Argus  pheasant  does  not  possess  brilliant 
colors,  so  that  his  success  in  love  appears  to  depend  on  the 
great  size  of  his  plumes  and  on  the  elaboration  of  the  most 
elegant  patterns.  Many  will  declare  that  it  is  utterly  in- 
credible that  a  female  bird  should  be  able  to  appreciate  fine 
shading  and  exquisite  patterns.     It  is  undoubtedly  a  mar- 


454  THE  DESCENT  OF  MAN, 

velous  fact  that  she  should  possess  this  almost  human  degree 
of  taste.  He  who  tliinks  that  he  can  safely  gauge  the  dis- 
crimination and  taste  of  the  lower  animals  may  deny  that 
the  female  Argus  pheasant  can  appreciate  such  refined 
beauty;  but  he  will  then  be  compelled  to  admit  that  the 
extraordinary  attitudes  assumed  by  the  male  during  the  act 
of  courtship,  by  which  the  wonderful  beauty  of  his  plum- 
age is  fully  displayed,  are  purposeless;  and  this  is  a  conclu- 
sion which  I  for  one  will  never  admit. 

Although  so  many  pheasants  and  allied  gallinaceous 
birds  carefully  display  their  phimage  before  the  females,  it 
is  remarkable,  as  Mr.  Bartlett  informs  me,  that  this  is  not 
the  case  with  the  dull  colored  eared  and  cheer  pheasants 
{Crossoptilon  auritum  and  Fhasianus  wallichii);  so  that 
these  birds  seem  conscious  that  they  have  little  beauty  to 
display.  Mr.  Bartlett  has  never  seen  the  males  of  either  of 
these  species  fighting  together,  though  he  has  not  had  such 
good  opportunities  for  observing  the  cheer  as  the  eared 
pheasant.  Mr.  Jenner  Weir,  also,  finds  that  all  male 
birds  with  rich  or  strongly-characterized  plumage  are  more 
quarrelsome  than  the  dull-colored  species  belonging  to  the 
same  groups.  The  goldfinch,  for  instance,  is  far  more 
pugnacious  than  the  linnet,  and  the  blackbird  than  the 
thrush.  Those  birds  which  undergo  a  seasonal  change  of 
plumage  likewise  become  much  more  pugnacious  at  the 
period  when  they  are  most  gayly  ornamented.  No  doubt 
the  males  of  some  obscurely  colored  birds  fight  desperately 
together,  but  it  appears  that  when  sexual  selection  has 
been  highly  influential,  and  has  given  bright  colors  to  the 
males  of  any  species,  it  has  also  very  often  given  a  strong 
tendency  to  pugnacity.  We  shall  meet  with  nearly  analo- 
gous cases  when  we  treat  of  mammals.  On  the  other  hand, 
with  birds  the  power  of  song  and  brilliant  colors  have 
rarely  been  both  acquired  by  the  males  of  the  same  species; 
but  in  this  case  the  advantage  gained  would  have  been  the 
same,  namely,  success  in  charming  the  female.  Neverthe- 
less it  must  be  owned  that  the  males  of  several  brilliantly 
colored  birds  have  had  their  feathers  specially  modified  for 
the  sake  of  producing  instrumental  music,  though  the 
beauty  of  this  cannot  be  compared,  at  least  according  to 
our  taste,  with  that  of  the  vocal  music  of  many  songsters. 

We  will  now  turn  to  male  birds  which  are  not  orna- 
mented in  any  high  degree,  but  which  nevertheless  display 


BIRDIE  455 

during  tlieir  courtship  whatever  attractions  they  may  pos- 
sess. These  cases  are  in  some  respects  more  curious  than 
the  foregoing,  and  have  been  but  little  noticed.  I  owe  the 
following  facts  to  Mr.  AVeir,  who  has  long  kept  confined 
birds  of  many  kinds,  including  all  the  British  Fringillidse 
and  Emberizidae.  The  facts  have  been  selected  from  a 
large  body  of  valuable  notes  kindly  sent  me  by  him.  The 
bullfinch  makes  his  advances  in  front  of  the  female,  and 
then  puffs  out  his  breast,  so  that  many  more  of  the  crim- 
son feathers  are  seen  at  once  than  otherwise  would  be  the 
case.  At  the  same  time  he  twists  and  bows  his  black 
tail  from  side  to  side  in  a  ludricous  manner.  The  male 
chaffinch  also  stands  in  front  of  the  female,  thus  show- 
ing his  red  breast  and  "  blue  bell,"  as  the  fan- 
ciers call  his  head  ;  the  wings  at  the  same  time  being 
slightly  expanded,  with  the  pure  white  bands  on  the  shoul- 
ders thus  rendered  conspicuous.  The  common  linnet  dis- 
tends his  rosy  breast,  slightly  expands  his  brown  wings 
and  tail,  so  as  to  make  the  best  of  them  by  exhibiting  their 
white  edgings.  We  must,  however,  be  cautious  in  conclud- 
ing that  the  wings  are  spread  out  solely  for  display,  as 
some  birds  do  so  whose  wings  are  not  beautiful.  This  is 
the  case  with  the  domestic  cock,  but  it  is  always  the  wing 
on  the  side  opposite  to  the  female  which  is  expanded,  and 
at  the  same  time  scraped  on  the  ground.  The  male  gold- 
finch behaves  differently  from  all  other  finches;  his  wings 
are  beautiful,  the  shoulders  being  black,  with  the  dark- 
tipped  wing-feathers  spotted  with  white  and  edged  with 
golden  yellow.  When  he  courts  the  female  he  sways  his 
body  from  side  to  side,  and  quickly  turns  his  slightly 
expanded  wings  first  to  one  side  then  to  the  other  with  a 
golden  flashing  effect.  Mr.  Weir  informs  me  that  no  other 
British  finch  turns  thus  from  side  to  side  during  his  court- 
ship, not  even  the  closely  allied  male  siskin,  for  he  would 
not  thus  add  to  his  beauty. 

Most  of  the  British  buntings  are  plain-colored  birds ; 
but  in  the  spring  the  feathers  on  the  head  of  the  male 
reed-bunting  {Emberiza  scJmniculus)  acquire  a  fine  black 
color  by  the  abrasion  of  the  dusky  tips;  and  these  are 
erected  during  the  act  of  courtship.  Mr.  Weir  has  kept 
two  species  of  Amadina  from  Australia;  the  ^4.  castanotis 
is  a  very  small  and  chastely  colored  finch,  with  a  dark  tail, 
white  rump  and  jet-black  upper  tail  coverts,  each  of  the 


456  THE  DESCENT  OF  MAN. 

latter  being  marked  with  three  large  conspicuous  oval 
spots  of  white.*  This  species  when  courting  the  female 
slightly  spreads  out  and  vibrates  these  parti-colored  tail 
coverts  in  a  very  peculiar  manner.  The  male  Amadina 
Lathami  behaves  very  differently,  exhibiting  before  the 
female  his  brilliantly  spotted  breast,  scarlet  rump  and 
scarlet  upper  tail  coverts.  I  may  here  add  from  Dr. 
Jerdon  that  the  Indian  bulbul  {Pycno7iotus  limmorrhous) 
has  its  under  tail  coverts  of  a  crimson  color,  and  these,  it 
might  be  thought,  could  never  be  well  exhibited;  but  the 
bird  ^^  when  excited  often  spreads  them  out  laterally  so 
that  they  can  be  seen  even  from  above. ^'f  The  crimson 
under  tail  coverts  of  some  other  birds,  as  with  one  of  the 
woodpeckers,  Picus  major,  can  be  seen  without  any  such 
display.  The  common  pigeon  has  iridescent  feathers  on 
the  breast,  and  every  one  must  have  seen  how  the  male 
inflates  his  breast  while  courting  the  female,  thus  showing 
them  oft*  to  the  best  advantage.  One  of  the  beautiful 
bronze-winged  pigeons  of  Australia  {Ocyphaps  lophotes) 
behaves,  as  described  to  me  by  Mr.  Weir,  very  differently. 
The  male  while  standing  before  the  female  lowers  his  head 
almost  to  the  ground,  spreads  out  and  raises  his  tail  and 
half  expands  his  wings.  He  then  alternately  and  slowly 
raises  and  depresses  his  body,  so  that  the  iridescent 
metallic  feathers  are  all  seen  at  once  and  glitter  in  the  sun. 

Sufficient  facts  have  now  been  given  to  show  with  what 
care  male  birds  display  their  various  charms,  and  this  they 
do  with  the  utmost  skill.  While  preening  their  feathers 
they  have  frequent  opportunities  for  admiring  themselves 
and  of  studying  how  best  to  exhibit  their  beauty.  But  as 
all  the  males  of  the  same  species  display  themselves  in 
exactly  the  same  manner  it  appears  that  actions,  at  first 
perhaps  intentional,  have  become  instinctive.  If  so,  we 
ought  not  to  accuse  birds  of  conscious  vanity;  yet  when 
we  see  a  peacock  strutting  about  with  expanded  and 
quivering  tail  feathers  he  seems  the  very  emblem  of  pride 
and  vanity. 

The  various  ornaments  possessed  by  the  males  are  cer- 
tainly of  the  highest  importance  to  them,  for  in  some  cases 

*For  the  description  of  these  birds  see  Gould's  "  Hand-book  to  the 
Birds  of  Australia,"  vol.  i,  1865,  p.  417. 
f  "  Birds  of  India,"  vol.  ii,  p.  96. 


BIRDS.  451' 

they  have  been  acquired  at  the  expense  of  greatly  impeded 
powers  of  flight  or  of  running.  The  African  night-jar 
(Cosmetornis),  wliich  during  the  pairing-season  has  one  of 
its  primary  wing-feathers  developed  into  a  streamer  of  very 
great  length,  is  thereby  much  retarded  in  its  flight, 
although  at  other  times  remarkable  for  its  swiftness.  The 
^'^ unwieldy  size"  of  the  secondary  wing-feathers  of  the 
male  Argus  pheasant  is  said  ''^almost  entirely  to  deprive 
the  bird  of  flight."  The  fine  plumes  of  male  birds  of  para- 
dise trouble  them  during  a  high  wind.  The  extremely  long 
tail-feathers  of  the  male  widow-birds  (Vidua)  of  South- 
ern Africa  render  ''  their  flight  heavy;"  but  as  soon  as  these 
are  cast  off  they  fly  as  well  as  the  females.  As  birds  always 
breed  when  food  is  abundant,  the  males  probably  do  not 
suffer  much  inconvenience  in  searching  for  food  from  their 
impeded  powers  of  movement;  but  there  can  hardly  be  a 
doubt  that  they  must  be  much  more  liable  to  be  struck 
down  by  birds  of  prey.  Nor  can  we  doubt  that  the  long 
train  of  the  peacock  and  the  long  tail  and  wing  feathers  of 
the  Argus  pheasant  must  render  them  an  easier  prey  to  any 
prowling  tiger-cat  than  would  otherwise  be  the  case.  Even 
the  bright  colors  of  many  male  birds  cannot  fail  to  make 
them  conspicuous  to  their  enemies  of  all  kinds.  Hence, 
as  Mr.  Gould  has  remarked,  it  probably  is  that  such  birds 
are  generally  of  a  shy  disposition,  as  if  conscious  that  their 
beauty  was  a  source  of  danger,  and  are  much  more  difficult 
to  discover  or  approach  than  the  somber  colored  and  com- 
paratively tame  females  or  than  the  young  and  as  yet 
unadorned  males.* 

It  is  a  more  curious  fact  that  the  males  of  some  birds 
which  are  provided  with  special  weapons  for  battle,  and 
which  in  a  state  of  nature  are  so  pugnacious  that  they 
often  kill  each  other,  suffer  from  possessing  certain  orna- 
ments. Cock-tighters  trim  the  hackles  and  cut  off  the 
combs  and  gills  of  their  cocks;  and  the  birds  are  then  said 
to  be   dubbed.     An   undubbed   bird,  as  Mr.   Tegetmeier 

*0n  tlie  Cosmetornis,  see  Livingstone's  "  Expedition  to  the  Zam- 
besi," 1865,  p.  66.  On  the  Argus  plieasant,  Jardine's  "  Nat.  Hist. 
Lib.:  Birds,"  vol.  xiv,  p.  167.  On  birds  of  paradise,  Lesson,  quoted 
by  Brehm,  "  Thierleben,"  B.  iii,  s.  325.  On  the  widow-bird,  Bar- 
row's "Travels  in  Africa,"  vol.  i,  p.  243,  and  "Ibis,"  vol.  iii,  1861, 
p.  133.  Mr.  Gould,  on  the  shyness  of  male  birds,  "Hand-book  to 
Birds  of  Australia,"  vol.  i,  1865,  pp.  210,  457. 


458  THE  DESCENT  OF  MAN. 

insists,  "is  at  a  fearful  disadvantage;  the  comb  and  gills 
offer  an  easy  hold  to  his  adversary's  beak,  and  as  a  cock 
always  strikes  where  he  holds,  when  once  he  has  seized  his 
foe,  he  has  him  entirely  in  his  power.  Even  supposing 
that  the  bird  is  not  killed,  the  loss  of  blood  suffered  by  an 
undubbed  cock  is  much  greater  than  that  sustained  by  one 
that  has  been  trimmed/'*  Young  turkey-cocks  in  fighting 
always  seize  hold  of  each  other's  wattles;  and  I  presume 
that  the  old  birds  fight  in  the  same  manner.  It  may  per- 
haps be  objected  that  the  comb  and  wattles  are  not  orna- 
mental and  cannot  be  of  service  to  the  birds  in  this  way; 
but  even  to  our  eyes  the  beauty  of  the  glossy  black  Spanish 
cock  is  much  enhanced  by  his  white  face  and  crimson 
comb;  and  no  one  who  has  ever  seen  the  splended  blue 
wattles  of  the  male  Tragopan  pheasant  distended  in  court- 
ship can  for  a  moment  doubt  that  beauty  is  the  object 
gained.  From  the  foregoing  facts  we  clearly  see  that  the 
plumes  and  other  ornaments  of  the  males  must  be  of  the 
highest  importance  to  them;  and  we  further  see  that  beauty 
is  even  sometimes  more  important  than  success  in  battle. 

* Tegetmeier,  "The  Poultry  Book,"  1866,  p.  139. 


BmD8,  459 


CHAPTER  XIV. 

BIRDS — continued. 

Choice  exerted  by  the  female — Length  of  courtship — Unpaired  birds 
— Mental  qualities  and  taste  for  the  beautiful — Preference  or 
antipathy  shown  by  the  female  for  particular  males — Variability 
of  birds  —  Variations  sometimes  abrupt  —  Laws  of  variation — 
Formation  of  ocelli — Gradations  of  character — Case  of  peacock, 
Argus  pheasant  and  Urosticte. 

When  the  sexes  differ  in  beauty  or  in  the  power  of  sing- 
ing, or  in  producing  what  I  have  called  instrumental 
music,  it  is  almost  invariably  the  male  who  surpasses  the 
female.  These  qualities,  as  we  have  just  seen,  are  evidently 
of  high  importance  to  the  male.  When  they  are  gained 
for  only  a  part  of  the  year  it  is  always  before  the  breeding- 
season.  It  is  the  male  alone  who  elaborately  displays  his 
varied  attractions,  and  often  performs  strange  antics  on  the 
ground  or  in  the  air,  in  the  presence  of  the  female.  Each 
male  drives  away,  or,  if  he  can,  kills  his  rivals.  Hence  we 
may  conclude  that  it  is  the  object  of  the  male  to  induce 
the  female  to  pair  with  him,  and  for  this  purpose  he  tries 
to  excite  or  charm  her  in  various  ways;  and  this  is  the 
opinion  of  all  those  who  have  carefully  studied  the  habits 
of  living  birds.  But  there  remains  a  question  which  has 
an  all-important  bearing  on  sexual  selection,  namely,  does 
every  male  of  the  same  species  excite  and  attract  the 
female  equally?  Or  does  she  exert  a  choice  and  prefer 
certain  males?  This  latter  question  can  be  answered  in  the 
affirmative  by  much  direct  and  indirect  evidence.  It  is  far 
more  difficult  to  decide  what  qualities  determine  the  choice 
of  the  females;  but  here  again  we  have  some  direct  and 
indirect  evidence  that  it  is  to  a  large  extent  the  external 
attractions  of  the  male;  though  no  doubt  his  \\gOT,  cour- 
age, and  other  mental  qualities  come  into  play.  We  will 
begin  with  the  indirect  evidence. 


460  ^SE  DESCENT  OF  MAN. 

Length  of  Courtship. — The  lengthened  period  during 
which  both  sexes  of  certain  birds  meet  day  after  day  at  an 
appointed  place  probably  depends  partly  on  the  courtship 
being  a  prolonged  affair,  and  partly  on  reiteration  in  the 
act  of  pairing.  Thus  in  Germany  and  Scandinavia  the 
balzing  or  leks  of  the  black-cocks  last  from  the  middle  of 
March  all  through  April  into  May.  As  many  as  forty  or 
fifty  or  even  more  birds  congregate  at  the  leks;  and  the 
same  place  is  often  frequented  during  successive  years.  The 
lek  of  the  capercailzie  lasts  from  the  end  of  March  to  the 
middle  or  even  end  of  May.  In  North  America  "the 
partridge  dances"  of  the  Tetrao  phasianellus  ''last  for  a 
month  or  more."  Other  kinds  of  grouse,  both  in  North 
America  and  Eastern  Siberia,*  follow  nearly  the  same 
habits.  The  fowlers  discover  the  hillocks  where  the  ruffs 
congregate  by  the  grass  being  trampled  bare,  and  this  shows 
that  the  same  spot  is  long  frequented.  The  Indians  of 
Guiana  are  well  acquainted  with  the  cleared  arenas,  where 
they  expect  to  find  the  beautiful  cocks  of  the  rock;  and 
the  natives  of  New  Guinea  know  the  trees  where  from  ten 
to  twenty  male  birds  of  paradise  in  full  plumage  congre- 
gate. In  this  latter  case  it  is  not  expressly  stated  that  the 
females  meet  on  the  same  trees,  but  the  hunters,  if  not 
specially  asked,  would  probably  not  mention  their  presence, 
as  their  skins  are  valueless.  Small  parties  of  an  African 
weaver  (Ploceus)  congregate,  during  the  breeding-season, 
and  perform  for  hours  their  graceful  evolutions.  Large 
numbers  of  the  solitary  snipe  (Scolopax  major)  assemble 
during  dusk  in  a  morass;  and  the  same  place  is  frequented 
for  the  same  purpose  during  successive  years;  here  they 
may  be  seen  running  about  'Mike  so  many  large  rats," 
puffing  out  their  feathers,  flapping  their  wings,  and 
uttering  the  strangest  cries,  f 

*Nordman  describes  ("Bull.  Soc.  Imp.  des  Nat.  Moscou,"  1861, 
torn,  xxxiv,  p.  264)  the  balzen  of  Tetrao  urogalloides  in  Amur  Land. 
He  estimated  the  number  of  birds  assembled  at  above  a  hundred,  not 
counting  the  females,  which  lie  hid  in  the  surrounding  bushes.  The 
noises  uttered  differ  from  those  of  T.  urognllus. 

f  With  respect  to  the  assemblages  of  the  above-named  grouse,  see 
Brehm,  "Thierleben,"  B.  iv,  s.  350;  also  L.  Lloyd,  "Game  Birds  of 
Sweden,"  1867,  pp.  19,78.  Richardson,  "  Fauna  Bor.  Americana. : 
Birds,"  p.  362.  References  in  regard  to  the  assemblages  of  other 
birds  have  already  been  given.  On  Paradisea,  see  Wallace,  in 
"Annals  and  Mag.  of  Nat.  Hist.,"  vol.  xx,  1857,  p.  412.  On  the  snipe, 
Lloyd,  ibid,  p.  221. 


BIRDS.  461 

Some  of  the  above  birds — the  black-cock,  capercailzie, 
pheasant-grouse,  ruff,  solitary  snipe,  and  perhaps  others — 
are,  as  is  believed,  polygamists.  With  such  birds  it  might 
have  been  thought  that  the  stronger  males  would  simply 
have  driven  away  the  weaker,  and  then  at  once  have  taken 
possession  of  as  many  females  as  possible;  but  if  it  be  indis- 
pensable for  the  male  to  excite  or  please  the  female,  we  can 
understand  the  length  of  the  courtship  and  the  congrega- 
tion of  so  many  individuals  of  both  sexes  at  the  same  spot. 
Certain  strictly  monogamous  species  likewise  hold  nuptial 
assemblages;  this  seems  to  be  the  case  in  Scandinavia  with 
one  of  the  ptarmigans,  and  their  leks  last  from  the  middle 
of  March  to  the  middle  of  May.  In  Australia  the  lyre- 
birds (Menura  superha)  forms  '*  small  round  hillocks,"'  and 
the  M.  Alberti  scratches  for  itself  shallow  holes,  or,  as  they 
are  called  by  the  natives,  corrohorying  i^laces,  where  it  is 
believed  both  sexes  assemble.  The  meetings  of  the  M. 
superha  are  sometimes  very  large;  and  an  account  has 
lately  been  published  *  by  a  traveler,  who  heard  in  a  valley 
beneath  him,  thickly  covered  with  scrub,  "a  din  which 
completely  astonished "'  him  ;  on  crawling  onward  he 
beheld,  to  his  amazement,  about  one  hundred  and  fifty  of 
the  magnificent  lyre-cocks  ^^  ranged  in  order  of  battle 
and  fighting  with  indescribable  fury."'  The  bowers  of  the 
bower-birds  are  the  resort  of  both  sexes  during  the  breed- 
ing-season; and  *^  here  the  males  meet  and  contend  with 
each  other  for  the  favors  of  the  female,  and  here  the  latter 
assemble  and  coquet  with  -the  males.''  With  two  of  the 
genera,  the  same  bower  is  resorted  to  during  many  years,  f 

The  common  magpie  (Corvus  pica,  Linn.),  as  I  have 
been  informed  by  the  Kev.  W.  Darwin  Fox,  used  to 
assemble  from  all  parts  of  Delamere  forest,  in  order  to 
celebrate  the  ^^ great  magpie  marriage."  Some  years  ago 
these  birds  abounded  in  extraordinary  numbers,  so  that  a 
gamekeeper  killed  in  one  morning  nineteen  males,  and 
another  killed  by  a  single  shot  seven  birds  at  roost  together. 
They  then  had  the  habit  of  assembling  very  early  in  the 
spring  at  particular  spots,  where  they  could   be  seen  in 

*  Quoted  by  Mr.  T.  W  Wood  in  the  "  Student,"  April,  1870,  p. 
125. 

f  Gould,  "  Hand-book  to  the  Birds  of  Australia,"  vol.  i,  pp.  300, 
308,  448,  451.  On  the  ptarmigan,  above  alluded  to,  see  Lloyd,  ibid, 
p.  129. 


462  THE  DESCENT  OF  MAN, 

flocks,  chattering,  sometimes  fighting,  bustling  and  flying 
about  the  trees.  The  whole  affair  was  evidently  consid- 
ered by  the  birds  as  one  of  the  highest  importance. 
Shortly  after  the  meeting  they  all  separated,  and  were  then 
observed  by  Mr.  Fox  and  others  to  be  paired  for  the 
season.  In  any  district  in  which  a  species  does  not  exist  in 
large  numbers  great  assemblages  cannot,  of  course,  be 
held,  and  the  same  species  may  have  different  habits  in  dif- 
ferent countries.  For  example,  I  have  heard  of  only  one 
instance,  from  Mr.  Wedderburn,  of  a  regular  assemblage 
of  black  game  in  Scotland,  yet  these  assemblages  are  so 
well  known  in  Uermany  and  Scandinavia  that  they  have 
received  special  names. 

Unpaired  Birds. — From  the  facts  now  given,  we  may 
conclude  that  the  courtship  of  birds  belonging  to  widely 
different  groups  is  often  a  prolonged,  delicate,  and  trouble- 
some affair.  There  is  even  reason  to  suspect,  improbable  as 
this  will  at  first  appear,  that  some  males  and  females  of  the 
same  species,  inhabiting  the  same  district,  do  not  always 
please  each  other,  and  consequently  do  not  pair.  Many 
accounts  have  been  published  of  either  the  male  or  female 
of  a  pair  having  been  shot  and  quickly  replaced  by 
another.  This  has  been  observed  more  frequently  with 
the  magpie  than  with  any  other  bird,  owing,  perhaps, 
to  its  conspicuous  appearance  and  nest.  The  illustrious 
Jenner  states  that  in  Wiltshire  one  of  a  pair  was  daily  shot 
no  less  than  seven  times  successively,  "  but  all  to  no  pur- 
pose, for  the  remaining  magpie  soon  found  another  mate;" 
and  the  last  pair  reared  their  young.  A  new  partner  is 
generally  found  on  the  succeeding  day  ;  but  Mr.  Thomp- 
son gives  the  case  of  one  being  replaced  on  the 
evening  of  the  same  day.  Even  after  the  eggs  are  hatched, 
if  one  of  the  old  birds  is  destroyed  a  mate  will  often  be 
found ;  this  occurred  after  an  interval  of  two  days  in  a  case 
recently  observed  by  one  of  Sir  J.  Lubbock^s  keepers.* 
The  first  and  most  obvious  conjecture  is  that  male  magpies 
must  be  much  more  numerous  than  females;  and  that  in  the 
above  cases,  as  well  as  in  many  others  which  could  be  given, 
the  males  alone  had  been  killed.     This  apparently  holds 

*0n  magpies,  Jenner,  in  "Phil.  Transact.,"  1824,  p.  21.  Macgil- 
livray,  "Hist.  British  Birds,"  vol.  i,  p.  570.  Thompson,  in  "Annals 
and  Mag.  of  Nat.  Hist.,"  vol.  vUi,  1842,  p.  494. 


BIRDS.  463 

good  in  some  instances,  for  the  gamekeepers  in  Delamere 
forest  assured  Mr.  Fox  that  the  magpies  and  carrion-crows 
which  they  formerly  killed  in  succession  in  large  numbers 
near  their  nests  were  all  males;  and  they  accounted  for  this 
fact  by  the  males  being  easily  killed  while  bringing  food  to 
the  sitting  females.  Macgillivray,  however,  gives,  on  the 
authority  of  an  excellent  observer,  an  instance  of  three  mag- 
pies successively  killed  on  the  same  nest,  which  were  all 
females:  and  another  case  of  six  magpies  successively  killed 
while  sitting  on  the  same  eggs,  which  renders  it  probable 
that  most  of  them  were  females;  though,  as  I  hear  from 
Mr.  Fox,  the  male  will  sit  on  the  eggs  when  the  female  is 
killed. 

Sir  J.  Lubbock^'s  gamekeeper  has  repeatedly  shot,  but 
how  often  he  could  not  say,  one  of  a  pair  of  jays  ( Garruhis 
glandarius),  and  has  never  failed  shortly  afterward  to  find 
the  survivor  rematched.  Mr.  Fox,  Mr.  F.  Bond  and  others 
have  shot  one  of  a  pair  of  carrion-crows  {Corvus  corone),  but 
the  nest  was  soon  again  tenanted  by  a  pair.  These  birds 
are  rather  common;  but  the  peregrine-falcon  {Falco pere- 
grmus)  is  rare,  yet  Mr.  Thompson  states  that  in  Ireland  '^  if 
either  an  old  male  or  female  be  killed  in  the  breeding- 
season  (not  an  uncommon  circumstance)  another  mate 
is  found  within  a  very  few  days,  so  that  the  eyries,  not- 
withstanding such  casualties,  are  sure  to  turn  out  their 
complement  of  young. ^'  Mr.  Jenner  Weir  has  known  the 
same  thing  with  the  peregrine-falcons  at  Beachy  Head. 
The  same  observer  informs  me  that  three  kestrels  {Falco 
tinnunculus),  all  males,  were  killed,  one  after  the  other, 
while  attending  the  same  nest;  two  of  these  were  in  mature 
plumage,  but  the  third  was  in  the  plumage  of  the  previous 
year.  Even  with  the  rare  golden  eagle  (Aqiiila  chrysaetos), 
Mr.  Birkbeck  was  assured  by  a  trustworthy  gamekeeper  in 
Scotland,  that  if  one  is  killed  another  is  soon  found.  So 
with  the  white  owl  {Strix  fiammea)  "  t\iQ  survivor  readily 
found  a  mate,  and  the  mischief  went  on." 

White  of  Selborne,  who  gives  the  case  of  the  owl,  adds 
that  he  knew  a  man,  who,  from  believing  that  partridges 
when  paired  were  disturbed  by  the  males  fighting,  used  to 
shoot  them;  and  though  he  had  widowed  the  same  female 
several  times,  she  always  soon  found  a  fresh  partner.  This 
same  naturalist  ordered  the  sparrows,  which  deprived  the 
house-martins  of  their  nests,  to  b^  shot^  but  the  one  which 


464  THE  DESCENT  OF  MAN. 

was  left,  "be  it  cock  or  hen,  presently  procured  a  mate, 
and  so  for  several  times  following/'  I  could  add  analogous 
cases  relating  to  the  chaffinch,  nightingale  and  redstart. 
With  respect  to  the  latter  bird  {Phoenicura  ruticilla),  a 
writer'  expresses  much  surprise  how  the  sitting  female  could 
so  soon  have  given  effectual  notice  that  she  was  a  widow,  for 
the  species  was  not  common  in  the  neighborhood.  Mr.  Jenner 
AVeir  has  mentioned  to  me  a  nearly  similar  case;  at  Blackheath 
he  never  sees  or  hears  the  note  of  the  wild  bulltinch,  yet 
when  one  of  his  caged  males  has  died  a  wild  one  in  the 
course  of  a  few  days  has  generally  come  and  perched  near 
the  widowed  female,  whose  call-note  is  not  loud.  I  will 
give  only  one  other  fact,  on  the  authority  of  this  same 
observer;  one  of  a  pair  of  starlings  [Sturnus  vulgaris)  was 
shot  in  the  morning;  by  noon  a  new  mate  was  found;  this 
was  again  shot,  but  before  night  the  pair  was  complete;  so 
that  the  disconsolate  widow  or  widower  was  thrice  consoled 
during  the  same  day.  Mr.  Engleheart  also  informs  me 
that  he  used  during  several  years  to  shoot  one  of  a  pair  of 
starlings  which  built  in  a  hole  in  a  house  at  Blackheath; 
but  the  loss  was  always  immediately  repaired.  During  one 
season  he  kept  an  account,  and  found  that  he  had  shot 
thirty-five  birds  from  the  same  nest;  these  consisted  of 
both  males  and  females,  but  in  what  proportion  he  could 
not  say;  nevertheless,  after  all  this  destruction,  a  brood  was 
reared.* 

These  facts  well  deserve  attention.  How  is  it  that  there 
are  birds  enough  ready  to  replace  immediately  a  lost -mate 
of  either  sex?  Magpies,  jays,  carrion-crows,  partridges, 
and  some  other  birds  are  always  seen  during  the  spring  in 
pairs,  and  never  by  themselves;  and  these  offer  at  first  sight 
the  most  perplexing  cases.  But  birds  of  the  same  sex, 
although  of  course  not  truly  paired,  sometimes  live  in  pairs 
or  in  small  parties,  as  is  known  to  be  the  case  with  pigeons 
and  partridges.  Birds  also  sometimes  live  in  triplets,  as 
has  been  observed  with  starlings,  carrion-crows,  parrots 
and  partridges.     With  partridges  two  females  have  been 

*  On  the  peregrine  falcon,  see  Thompson,  "Nat.  Hist,  of  Ireland: 
Birds,"  vol.  i,  1849,  p.  39.  On  owls,  sparrows  and  partridges,  see 
White,  "  Nat.  Hist,  of  Selborne,"  edit,  of  1825,  vol.  i,  p.  139.  On 
the  Phoenicura,  see  Loudon's  "  Mag.  of  Nat.  Hist.,"  vol.  vii,  1834,  p. 
345.  Brehm  ("  Thierleben,"  B.  iv,  s.  991)  also  alludes  to  cases  of 
birds  thrice  mate<J  during  the  same  daj^. 


BIRDS.  465 

known  to  live  with  one  male,  and  two  males  with  one 
female.  In  all  such  cases  it  is  probable  that  the  union 
would  be  easily  broken;  and  one  of  the  three  would  readily 
pair  with  a  widow  or  widower.  The  males  of  certain  birds 
may  occasionally  be  heard  pouring  forth  their  love-song 
long  after  the  proper  time,  showing  that  they  have  either 
lost  or  never  gained  a  mate.  Death  from  accident  or  dis- 
ease of  one  of  a  pair  would  leave  the  other  free  and  single; 
and  there  is  reason  to  believe  that  female  birds  during  the 
breeding-season  are  especially  liable  to  premature  death. 
Again,  birds  which  have  had  their  nests  destroyed,  or 
barren  pairs,  or  retarded  individuals,  would  easily  be 
induced  to  desert  their  mates,  and  would  probably  be  glad 
to  take  what  share  tliey  could  of  the  pleasures  and  duties 
of  rearing  offspring,  altliough  not  their  own.*  Such  con- 
tingencies as  these  probably  explain  most  of  the  foregoing 
cases,  f  Nevertheless,  it  is  a  strange  fact  that  within  the 
same  district,  during  the  height  of  the  breeding-season, 
there  should  be  so  many  males  and  females  always  ready  to 
repair  the  loss  of  a  mated  bird.  Why  do  not  such  spare 
birds  immediately  pair  together?  Have  we  not  some  reason 
to  suspect,  and  the  suspicion  has  occurred  to  Mr.  Jenner 
Weir,  that,  as  the  courtship  of  birds  appears  to  be  in  many 

*  See  White  ("  Nat.  Hist,  of  Selborne,"  1825,  vol.  i,  p.  140)  on  tbe 
existence,  early  in  the  season,  of  small  coveys  of  male  partridges,  of 
which  fact  I  have  heard  other  instances.  See  Jenner,  on  the  retarded 
state  of  the  generative  organs  in  certain  birds,  in  "Phil.  Transact." 
1824.  In  regard  to  birds  living  in  triplets,  I  owe  to  Mr.  Jenner  Weir 
the  cases  of  the  starlings  and  parrots,  and  to  Mr.  Fox,  of  partridges; 
on  carrion-crows,  see  the  "  Field,"  1868,  p.  415.  On  various  male 
birds  singing  after  the  proper  period,  see  Rev.  L.  Jenyns,  "Ob- 
servations in  Natural  History,"  1846,  p.  87. 

f  The  following  case  has  been  given  ("The  Times,"  Aug.  6,  1868) 
by  the  Rev.  F.  0.  Morris,  on  the  authority  of  the  Hon.  and  Rev.  O. 
W.  Forester.  "  The  gamekeeper  here  found  a  hawk's  nest  this  year 
with  five  young  ones  in  it.  He  took  four  and  killed  them,  but  left 
one  with  its  wings  clipped  as  a  decoy  to  destroy  the  old  ones  by. 
They  were  both  shot  next  day  in  the  act  of  feeding  the  young  one, 
and  the  keeper  thought  it  was  done  with.  The  next  day  he  came 
again  and  found  two  other  charitable  hawks  who  had  come  with  an 
adopted  feeling  to  succor  the  orphan.  These  two  he  killed  and  then 
left  the  nest.  On  returning  afterward  he  found  two  more  charitable 
individuals  on  the  same  errand  of  mercy.  One  of  these  he  killed; 
the  other  he  also  shot  but  could  not  Ijjjd*  No  more  came  on  the  like 
fruitless  errand. " 


466  THE  DESCENT  OF  MAN. 

cases  prolonged  and  tedious,  so  it  occasionally  happens  that 
certain  males  and  females  do  not  succeed,  during  the  proper 
season,  in  exciting  each  other's  love,  and  consequently  do 
not  pair?  This  suspicion  will  appear  somewhat  less  improba- 
ble after  we  have  seen  what  strong  antipathies  and  prefer- 
ences female  birds  occasionally  evince  toward  particular 
males. 

Mental  Qualities  of  Birds  and  Tlieir  Taste  for  the 
Beantifid, — Before  we  further  discuss  the  question  whether 
the  females  select  the  more  attractive  males  or  accept  the 
first  whom  they  may  encounter,  it  will  be  advisable  briefly 
to  consider  the  mental  powers  of  birds.  Their  reason  is 
generally,  and  perhaps  justly,  ranked  as  low;  yet  some  facts 
could  be  given*  leading  to  an  opposite  conclusion.  Low 
powers  of  reasoning,  however,  are  compatible,  as  we  see 
with  mankind,  with  strong  affections,  acute  perception, 
and  a  taste  for  the  beautiful;  and  it  is  with  these  latter 
qualities  that  we  are  here  concerned.  It  has  often  been 
said  that  parrots  become  so  deeply  attached  to  each  other 
that  when  one  dies  the  other  pmes  for  a  long  time;  but 
Mr.  Jenner  Weir  thinks  that  with  most  birds  the  strength 
of  their  affection  has  been  much  exaggerated.  Neverthe- 
less, when  one  of  a  pair  \\\  a  state  of  nature  has  been  shot, 
the  survivor  has  been  heard  for  days  afterward  uttering  a 
plaintive  call;  and  Mr.  St.  John  gives  various  facts  proving 
the  attachment  of  mated  birds.  \  Mr.  Bennett  relates];  that 
in  China  after  a  drake  of  the  beautiful  mandarin  teal  had 
been  stolen  the  duck  remained  disconsolate,  though  sedu- 
lously courted  by  another  mandarin  drake,  who  displayed 

*  I  am  indebted  to  Prof.  Newton  for  the  following  passage  from 
Mr.  Adam's  "Travels  of  a  Naturalist,"  1870,  p.  278.  Speaking  of 
Japanese  nut-hate  lies  in  confinement,  be  says:  "  Instead  of  tbe  more 
yielding  fruit  of  tbe  yew,  wbicb  is  tbe  usual  food  of  tbe  nut-batcb 
of  Japan,  at  one  time  I  substituted  bard  bazel-nuts.  As  tbe  bird 
was  unable  to  crack  tbem,  be  placed  tbem  one  by  one  in  bis  water- 
glass,  evidently  witb  tbe  notion  tbat  tbey  would  in  time  become 
softer — an  interesting  proof  of  intelligence  on  tbe  part  of  tbese 
birds." 

f'A  Tour  in  Sutberlandsbire,"  vol.  i,  1849,  p.  185.  Dr.  Buller 
says  ("Birds  of  New  Zealand,"  1872,  p.  56)  tbat  a  male  King  Lory 
was  killed;  and  tbe  female  "  fretted  and  moped,  refused  ber  food, 
and  died  of  a  broken  beart." 

\  "  Wanderings  in  New  South  Wales,"  vol.  ii,  1834,  p.  62, 


BIRDS.  467 

before  her  all  his  charms.  After  an  interval  of  three  weeks 
the  stolen  drake  was  recovered,  and  instantly  the  pair 
recognized  each  ot'ner  with  extreme  joy.  On  the  other 
hand  starlings,  as  we  have  seen,  may  be  consoled  thrice  in 
the  same  day  for  the  loss  of  their  mates.  Pigeons  have 
such  excellent  local  memories  that  they  have  been  known 
to  return  to  their  former  homes  after  an  interval  of  nine 
months,  yet,  as  I  hear  from  Mr.  Harrison  Weir,  if  a  pair 
which  naturally  would  remain  mated  for  life  be  separated 
for  a  few  weeks  during  the  winter,  and  afterward  matched 
with  other  birds,  the  two,  when  brought  together  again, 
rarely,  if  ever,  recognize  each  other. 

Birds  sometimes  exhibit  benevolent  feelings;  they  will 
feed  the  deserted  young  ones  even  of  distinct  species,  but 
this  perhaps  ought  to  be  considered  as  a  mistaken  instinct. 
They  will  feed,  as  shown  in  an  earlier  part  of  this  work, 
adult  birds  of  their  own  species  which  have  become  blind. 
Mr.  Buxton  gives  a  curious  account  of  a  parrot  which  took 
care  of  a  frost-bitten  and  crippled  bird  of  a  distinct  species, 
cleansed  her  feathers  and  defended  her  from  the  attacks  of 
the  other  parrots  which  roamed  freely  about  his  garden. 
It  is  a  still  more  curious  fact  that  these  birds  apparently 
evince  some  sympathy  for  the  pleasures  of  their  fellows. 
When  a  pair  of  cockatoos  made  a  nest  in  an  acacia  tree  ''  it 
was  ridiculous  to  see  the  extravagant  interest  taken  in  the 
matter  by  the  others  of  tiie  same  species.  These  parrots 
also  evinced  unbounded  curiosity  and  clearly  had  "  the 
idea  of  property  and  possession."*  They  have  good  mem- 
ories, for  in  the  Zoological  Gardens  they  have  plainly 
recognized  their  former  masters  after  an  interval  of  some 
months. 

Birds  possess  acute  powers  of  observation.  Every  mated 
bird,  of  course,  recognizes  its  fellow.  Audubon  states  that 
a  certain  number  of  mocking-thrushes  (Mimus  polyglot f us) 
remain  all  the  year  round  in  Louisiana,  while  others 
migrate  to  the  Eastern  States;  these  latter  on  their  return 
are  instantly  recognized  and  always  attacked  by  their 
southern  brethren.  Birds  under  confinement  distinguish 
different  persons,  as  is  proved  by  the  strong  and  permanent 
antipathy  or  affection  which  they  show  without  any  appar- 

*  "  Acclimatization  of  Parrots,"  by  C.  Buxton,  M.  P.  "  Annals  and 
Mag.  of  Nat.  Hist.,"  Nov.,  1868,  p.  381. 


468  THE  DESCENT  OF  MAN. 

ent  cause  toward  certain  individuals.  I  have  heard  of 
numerous  instances  with  jays,  partridges,  canaries,  and 
especially  bullfinches.  Mr.  Hussey  has  described  in  how 
extraordinary  a  manner  a  tamed  partridge  recognized 
everybody;  and  its  likes  and  dislikes  were  very  strong. 
This  bird  seemed  ^'fond  of  gay  colors,  and  no  new  gown 
or  cap  could  be  put  on  without  catching  his  attention."* 
Mr.  Hewitt  has  described  the  habits  of  some  ducks 
(recently  descended  from  wild  birds)  which  at  the  approach 
of  a  strange  dog  or  cat  would  rush  headlong  into  the  water 
and  exhaust  themselves  in  their  attempts  to  escape;  but 
they  knew  Mr.  Hewitt's  own  dogs  and  cats  so  well  that 
they  would  lie  down  and  bask  in  the  sun  close  to  them. 
They  always  moved  away  from  a  strange  man,  and  so  they 
would  from  the  lady  who  attended  them  if  she  made  any 
great  change  in  her  dress.  Audubon  relates  that  he  reared 
and  tamed  a  wild  turkey  which  always  ran  away  from  any 
strange  dog;  this  bird  escaped  into  the  woods,  and  some 
days  afterward  Audubon  saw,  as  he  thought,  a  wild  turkey 
and  made  his  dog  chase  it;  but  to  his  astonishment  the 
bird  did  not  run  away,  and  the  dog  when  he  came  up  did 
not  attack  the  bird,  for  they  mutually  recognized  each 
other  as  old  friends,  f 

Mr.  Jenner  Weir  is  convinced  that  birds  pay  particular 
attention  to  the  colors  of  other  birds,  sometimes  out  of 
jealousy  and  sometimes  as  a  sign  of  kinship.  Thus  he 
turned  a  reed-bunting  {Emheriza  scJiceiiicidus),  which  had 
acquired  its  black  head-dress,  into  his  aviary,  and  the  new- 
comer was  not  noticed  by  any  bird  except  by  a  bullfinch, 
which  is  likewise  black-headed.  This  bullfinch  was  a  very 
quiet  bird,  and  had  never  before  quarreled  with  any  of  its 
comrades,  including  another  reed-bunting,  which  had  not 
as  yet  become  black-headed ;  but  the  reed-bunting  with  a 
black  head  was  so  unmercifully  treated  that  it  had  to  be 
removed.  8piza  cyauea,  during  the  breeding-season,  is  of 
a  bright  blue  color;  and  though  generally  peaceable,  it 
attacked  S.  ciris,  which  has  only  the  head  blue,  and  com- 
pletely scalped  the  unfortunate  bird.     Mr.  Weir  was  also 

*"  The  Zoologist,"  1847-1848,  p.  1602. 

f  Hewitt  on  wild  ducks,  "  Journal  of  Horticulture,"  Jan.  13,  1863, 
p.  39,  Audubon  on  the  wild  turkey,  "  Ornith.  Biography,"  vol.  i,  p. 
14.    On  the  mocking-thrush,  ibid,  vol.  i,  p.  110. 


BIRDS,  469 

obliged  to  turn  out  a  robin,  as  it  fiercely  attacked  all  the 
birds  in  his  aviary  with  anj  red  in  their  plumage,  but  no 
other  kinds;  it  actually  killed  a  red-brested  crossbill  and 
nearly  killed  a  goldfinch.  On  the  other  hand,  he  has 
observed  that  some  birds,  when  first  introduced,  fly  toward 
the  species  which  resemble  them  most  in  color,  and  settle 
by  their  sides. 

As  male  birds  display  their  fine  plumage  and  other  orna- 
ments with  so  much  care  before  the  females,  it  is  obvi- 
ously probable  that  these  appreciate  the  beauty  of  their 
suitors.  It  is,  however,  difficult  to  obtain  direct  evidence 
of  their  capacity  to  appreciate  beauty.  When  birds  gaze 
at  themselves  in  a  looking-glass  (of  which  many  instances 
have  been  recorded)  we  cannot  feel  sure  that  it  is  not  from 
jealousy  of  a  supposed  rival,  though  this  is  not  the  conclu- 
sion of  some  observers.  In  other  cases  it  is  difficult  to  dis- 
tinguish between  mere  curiosity  and  admiration.  It  is 
perhaps  the  former  feeling  which,  as  stated  by  Lord  Lil- 
ford,*  attracts  the  ruif  toward  any  bright  object,  so  that, 
in  the  Ionian  Islands,  "  it  will  dart  down  to  a  bright-col- 
ored handkerchief,  regardless  of  repeated  shots."  The 
common  lark  is  drawn  down  from  the  sky,  and  is  caught 
in  large  numbers,  by  a  small  mirror  made  to  move  and 
glitter  in  the  sun.  Is  it  admiration  or  curiosity  which 
leads  the  magpie,  raven,  and  some  other  birds  to  steal  and 
secrete  bright  objects,  such  as  silver  articles  or  jewels? 

Mr.  Gould  states  that  certain  humming-birds  decorate 
the  outsides  of  their  nests  ^^  with  the  utmost  taste  ;  they 
instinctively  fasten  thereon  beautiful  pieces  of  flat  liclien, 
the  larger  pieces  in  the  middle,  and  the  smaller  on  the  part 
attached  to  the  branch.  Now  and  then  a  pretty  feather 
is  intertwined  or  fastened  to  the  outer  sides,  the  stem  being 
always  so  placed  that  the  feather  stands  out  beyond  the 
surface.''  The  best  evidence,  however,  of  a  taste  for  the 
beautiful  is  afforded  by  the  three  genera  of  Australian 
bower-birds  already  mentioned.  Their  bowers  (see  fig.  46), 
where  the  sexes  congregate  and  play  strange  antics, 
are  variously  constructed,  but  what  most  concerns  us  is, 
that  they  are  decorated  by  the  several  species  in  a  different 
manner.  The  satin  bower-bird  collects  gayly-colored  arti- 
cles, such  as  the  blue  tail-feathers  of  paroquets,  bleached 

*The  "Ibis,"  vol.  ii.  1860,  p.  344. 


470  ^^^  DESCENT  OF  MAN. 

bones  and  shells,  which  it  sticks  between  the  twigs  or 
arranges  at  the  entrance.  Mr.  Gould  found  in  one  bower 
a  neatly- worked  stone  tomahawk  and  a  slip  of  blue  cotton, 
evidently  procured  from  a  native  encampment.  These 
objects  are  continually  rearranged,  and  carried  about  by 
the  birds  while  at  play.  The  bower  of  the  spotted  bower- 
bird  **  is  beautifully  lined  with  tall  grasses,  so  disposed  that 
the  heads  nearly  meet,  and  the  decorations  are  very  profuse.'' 
Eound  stones  are  used  to  keep  the  grass-stems  in  their 
proper  places  and  to  make  divergent  paths  leading  to  the 
bower.  The  stones  and  shells  are  often  brought  from  a 
great  distance.  The  regent  bird,  as  described  by  Mr. 
Ramsay,  ornaments  its  short  bower  with  bleached  land- 
shells  belonging  to  five  or  six  species,  and  with  *^  berries  of 
various  colors,  blue,  red,  and  black,  which  give  it  when 
fresh  a  very  pretty  appearance.  Besides  these  there  were 
several  newly-picked  leaves  and  young  shoots  of  a  pinkish 
color,  the  whole  showing  a  decided  taste  for  the  beautiful." 
Well  may  Mr.  Gould  say  that  '^  these  highly  decorated 
halls  of  assembly  must  be  regarded  as  the  most  wonderful 
instances  of  bird-architecture  yet  discovered;"  and  the 
taste,  as  we  see,  of  the  several  species  certainly  differs.  * 

Preference  for  Particular  Males  hy  the  Females. — Having 
made  these  preliminary  remarks  on  the  discrimination  and 
taste  of  birds,  I  will  give  all  the  facts  known  to  me  which 
bear  on  the  preference  shown  by  the  female  for  particular 
males.  It  is  certain  that  distinct  species  of  birds  occasion- 
ally pair  in  a  state  of  nature  and  produce  hybrids.  Many 
instances  could  be  given;  thus  Macgillivray  relates  how  a 
male  blackbird  and  female  thrush  "  fell  in  love  with  each 
other,"  and  produced  offspring.!  Several  years  ago  eight- 
een cases  had  been  recorded  of  the  occurrence  in  Great 
Britain  of  hybrids  between  the  black  grouse  and  pheasant  ;| 
but  most  of  these  cases  may  perhaps  be  accounted  for  by 
solitary  birds  not  finding  one  of  their  own  species  to  pair 
with.     With  other  birds,  as  Mr.  Jenner  Weir  has  reason  to 

*  On  the  ornamental  nests  of  humming-birds,  Gould,  "Introduc- 
tion to  the  Trochilidae,  1861,  p.  19.  On  the  bower-birds,  Gould, 
"  Hand-book  to  the  Birds  of  Australia,"  1865,  vol.  i,  pp.  444-461. 
Ramsay,  in  the  "  Ibis,"  1867,  p.  456. 

f  "  Hist,  of  British  Birds,"  vol.  ii,  p.  92. 

t"  Zoologist,"  1853-1854,  p.  3940. 


BIRDS.  4'J'l 

believe,  hybrids  are  sometimes  the  result  of  the  casual  inter- 
course of  birds  building  in  close  proximity.  But  these 
remarks  do  not  apply  to  the  many  recorded  instances  of 
tamed  or  domestic  birds,  belonging  to  distinct  species, 
which  have  become  absolutely  fascinated  with  each  other, 
although  living  with  their  own  species.  Thus  Waterton* 
states  that  out  of  a  flock  of  twenty-three  Canada  geese,  a 
female  paired  with  a  solitary  Bernicle  gander,  although  so 
different  in  appearance  and  size;  and  they  produced  hybrid 
offspring.  A  male  wigeon  {Mareca  penelope)  living  with 
females  of  the  same  species  has  been  known  to  pair  with  a 
pintail  duck,  Qiierquedula  acuta.  Lloyd  describes  the  re- 
markable attachment  between  a  shield-drake  {Tadorna 
vulpanser)  and  a  common  duck.  Many  additional  instances 
could  be  given;  and  the  Rev,  E.  S.  Dixon  remarks  that 
"  those  who  have  kept  many  different  species  of  geese 
together  well  know  what  unaccountable  attachments  they 
are  frequently  forming,  and  that  they  are  quite  as  likely  to 
pair  and  rear  young  with  individuals  of  a  race  (species) 
apparently  the  most  alien  to  themselves  as  with  their  own 
stock." 

The  Rev.  W.  D.  Fox  informs  me  that  he  possessed  at  the 
same  time  a  pair  of  Chinese  geese  {Anser  Cygnoides)  and  a 
common  gander  with  three  geese.  The  two  lots  kept  quite 
separate,  until  the  Chinese  gander  seduced  one  of  the 
common  geese  to  live  with  him.  Moreover,  of  the  young 
birds  hatched  from  the  eggs  of  the  common  geese,  only 
four  were  pure,  the  other  eighteen  proving  hybrids;  so  that 
the  Chinese  gander  seems  to  have  had  prepotent  charms 
over  the  common  gander.  I  will  give  only  one  other  case: 
Mr.  Hewitt  states  that  a  wild  duck,  reared  in  captivity, 
"  after  breeding  a  couple  of  seasons  with  her  own  mallard, 
at  once  shook  him  off  on  my  placing  a  male  pintail  on  the 
water.  It  was  evidently  a  case  of  love  at  first  sight,  for 
she  swam  about  the  new-comer  caressingly,  though  he 
appeared  evidently  alarmed  and  averse  to  her  overtures  of 

♦Waterton,  "  Essays  on  Nat.  Hist.,"  2d  series,  pp.  42,  117.  For 
tbe  following  statements  see  on  the  wigeon,  Loudon's  "  Mag.  of  Nat. 
Hist.,"  vol.  ix,  p.  616.  L.  Llovd,  "  Scandinavian  Adventures."  vol.  i, 
1854,  p.  452.  Dixon,  "  Ornamental  and  Domestic  Poultry,"  p.  137; 
Hewitt,  in  "Journal  of  Horticulture,"  Jan.  13,  1863,  p.  40;  Becb- 
stein,  "  Stubenvogel,"  1840,  s.  230.  Mr.  Jenner  Weir  has  lately 
given  me  an  analogous  case  with  ducks  of  two  species. 


4n  THE  DESCENT  OF  MAN. 

affection.  From  that  hour  she  forgot  her  old  partner. 
Winter  passed  by,  and  the  next  spring  the  pintail  seemed 
to  have  become  a  convert  to  her  blandishments,  for  they 
nested  and  produed  seven  or  eight  young  ones." 

What  the  charm  may  have  been  in  these  several  cases, 
beyond  mere  novelty,  we  cannot  even  conjecture.  Color, 
however,  sometimes  comes  into  play;  for  in  order  to  raise 
hybrids  from  the  siskin  (Frmgilla  spinus)  and  the  canary, 
it  is  much  the  best  plan,  according  to  Bechstein,  to  place 
birds  of  the  same  tint  together.  Mr.  Jenner  Weir  turned 
a  female  canary  into  his  aviary,  where  there  were  male 
linnets,  goldfinches,  siskins,  greenfinches,  chaffinches  and 
other  birds,  in  order  to  see  which  she  would  choose;  but 
there  never  was  any  doubt,  and  the  greenfinch  carried  the 
day.     They  paired  and  produced  hybrid  offspring. 

The  fact  of  the  female  preferring  to  pair  with  one  male 
rather  than  with  another  of  the  same  species  is  not  so  likely 
to  excite  attention  as  when  this  occurs,  as  we  have  just 
seen,  between  distinct  species.  The  former  cases  can  best 
be  olDserved  with  domesticated  or  confined  birds;  but  these 
are  often  pampered  by  high  feeding,  and  sometimes  have 
their  instincts  vitiated  to  an  extreme  degree.  Of  this  latter 
fact  I  could  give  sufficient  proofs  with  pigeons,  and  espe- 
cially with  fowls,  but  they  cannot  be  here  related.  Vitiated 
instincts  may  also  account  for  some  of  the  hybrid  unions 
above  mentioned;  but  in  many  of  these  cases  the  birds  were 
allowed  to  range  freely  over  large  ponds,  and  there  is  no 
reason  to  suppose  that  they  were  unnaturally  stimulated  by 
high  feeding. 

With  respect  to  birds  in  a  state  of  nature,  the  first  and 
most  obvious  supposition  which  will  occur  to  every  one  is 
that  the  female  at  the  proper  season  accepts  the  first  male 
whom  she  may  encounter;  but  she  has  at  least  the  oppor- 
tunity for  exerting  a  choice,  as  she  is  almost  invariably 
pursued  by  many  males.  Audubon — and  we  must  remem- 
ber that  he  spent  a  long  life  in  prowling  about  the  forests 
of  the  United  States  and  observing  the  birds — does  not 
doubt  that  the  female  deliberately  chooses  her  mate;  thus, 
speaking  of  a  woodpecker,  he  says  the  hen  is  followed  by 
half  a  dozen  gay  suitors,  who  continue  performing  strange 
antics,  "  until  a  marked  preference  is  shown  for  one."*  The 
female  of  the  red- winged  starling  {Agelmtis  phmiicens)  is 
likewise    pursued    by   several    males ;    "  until,    becoming 


BIRDS.  473 

faticrued,  she  alights,  receives  their  addresses,  and  soon 
makes  a  choice."  He  describes  also  how  several  male 
night-jars  repeatedly  plunge  through  the  air  with  astonish- 
ing rapidity,  suddenly  turning,  and  thus  making  a  singular 
noise;  ''  but  no  sooner  has  the  female  made  her  choice  than 
the  other  males  are  driven  away."  With  one  of  the 
vultures  {Cathartes  aura)  of  the  United  States,  parties  of 
eighty  ten,  or  more  males  and  females  assemble  on  fallen 
logs,  *^  exhibiting  the  strongest  desire  to  please  mutually," 
and  after  many  caresses  each  male  leads  off  his  partner  on 
the  wing.  Audubon  likewise  carefully  observed  the  wild 
flocks  of  Canada  geese  {Anser  canadensis),  and  gives  a 
graphic  description  of  their  love  antics;  he  says  that  the 
birds  which  had  been  previously  mated  ^^ renewed  their 
courtship  as  early  as  the  month  of  January,  while  the 
others  would  be  contending  or  coquetting  for  hours  every 
day,  until  all  seemed  satisfied  with  the  choice  they  had 
made,  after  which,  although  they  remained  together,  any 
person  could  easily  perceive  that  they  were  careful  to  keep 
in  pairs.  I  have  observed  also  that  the  older  the  birds  the 
shorter  were  the  preliminaries  of  their  courtship.  The 
bachelors  and  old  maids,  whether  in  regret  or  not  caring 
to  be  disturbed  by  the  bustle,  quietly  moved  aside  and  lay 
down  at  some  distance  from  the  rest."*  Many  similar 
statements  with  respect  to  other  birds  could  be  cited  from 
this  same  observer. 

Turning  now  to  domesticated  and  confined  birds,  I  will 
commence  by  giving  what  little  I  have  learned  respecting 
the  courtship  of  fowls.  I  have  recieved  long  letters  on  this 
subject  from  Messrs.  Hewitt  and  Tegetmeier,  and  almost 
an  essay  from  the  late  Mr.  Brent.  It  will  be  admitted  by 
every  one  that  these  gentlemen,  so  well  known  from  their 
published  works,  are  careful  and  experienced  observers. 
They  do  not  believe  that  the  females  prefer  certain  males 
on  account  of  the  beauty  of  their  plumage;  but  some  allow- 
ance must  be  made  for  the  artificial  state  under  which 
these  birds  have  long  been  kept.  Mr.  Tegetmeier  is  con- 
vinced that  a  gamecock,  though  disfigured  by  being  dubbed 
and  with  his  hackles  trimmed,  would  be  accepted  as  readily 
as  a  male  retaining  all  his  natural  ornaments.     Mr..  Brent, 

♦Audubon,  "Ornitholog.  Biography,"  vol.  i,  pp.  191,  349;  vol.  ii, 
pp.  42,  275:  vol.  iii,  p.  2. 


474  THE  DESCENT  OF  MAN. 

however,  admits  that  the  beauty  of  the  male  probably  aids 
in  exciting  the  female;  and  her  acquiescence  is  necessary. 
Mr.  Hewitt  is  convinced  that  the  union  is  by  no  means  left 
to  mere  chance,  for  the  female  almost  invariably  prefers 
the  most  vigorous,  defiant  and  mettlesome  male;  hence  it 
is  almost  useless,  as  he  remarks,  ^'  to  attempt  true  breeding 
if  a  gamecock  in  good  health  and  condition  runs  the  local- 
ity, for  almost  every  hen  on  leaving  the  roosting-place  will 
resort  to  the  gamecock,  even  though  that  bird  may  not 
actually  drive  away  the  male  of  her  own  variety."  Under 
ordinary  circumstances  the  males  and  females  of  the  fowl 
seem  to  come  to  a  mutual  understanding  by  means  of  cer- 
tain gestures,  described  to  me  by  Mr.  Brent.  But  hens 
will  often  avoid  the  officious  attentions  of  young  males. 
Old  hens  and  hens  of  a  pugnacious  disposition,  as  the 
same  writer  informs  me,  dislike  strange  males,  and  will  not 
yield  until  well  beaten  into  compliance.  Ferguson,  how- 
ever, describes  how  a  quarrelsome  hen  was  subdued  by  the 
gentle  courtship  of  a  shanghai  cock.* 

There  is  reason  to  believe  that  pigeons  of  both  sexes 
prefer  pairing  with  birds  of  the  rame  breed;  and  dove-cote 
pigeons  dislike  all  the  highly  improved  breeds.  \  Mr.  Har- 
rison Weir  has  lately  heard  from  a  trustworthy  observer 
who  keeps  blue  pigeons  that  these  drive  away  all  other 
colored  varieties,  such  as  white,  red  and  yellow;  and  from 
another  observer,  that  a  female  dun  carrier  could  not,  after 
repeated  trials,  be  matched  wit^^  a  black  male,  but  imme- 
diately paired  with  a  dun.  Again,  Mr.  Tegetmeier  had  a 
female  blue  turbit  that  obstinately  refused  to  pair  with  two 
males  of  the  same  breed,  which  were  successively  shut  up 
with  her  for  weeks;  but  on  being  let  out  she  would  have 
immediately  accepted  the  first  blue  dragon  that  offered. 
As  she  was  a  valuable  bird,  she  was  then  shut  up  for  many 
weeks  with  a  silver  (^.  e.,  very  pale  blue)  male,  and  at  last 
mated  with  him.  Nevertheless,  as  a  general  rule,  color 
appears  to  have  little  influence  on  the  pairing  of  pigeons. 
Mr.  Tegetmeier,  at  my  request,  stained  some  of  his  birds 
with  magenta,  but  they  were  not  much  noticed  by  the 
others. 

*"Rare  and  Prize  Poultry,"  1854,  p.  27. 

f  "  The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  p.  103. 


STUDS,  475 

Female  pigeons  occasionally  feel  a  strong  antipathy  toward 
certain  males,  without  any  assignable  cause.  Thus  MM. 
Boitard  and  Corbie,  whose  experience  extended  over  forty- 
five  years,  state:  *'  Quand  une  femelle  eprouve  de  Tantip- 
athie  pour  un  mdle  avec  lequel  on  veut  Faccoupler,  malgre 
tons  les  feux  de  Tamour,  malgre  Talpiste  et  le  chenevis  dont 
on  la  nourrit  pour  augmenter  son  ardeur,  malgre  un  em- 
prisonnement  de  six  mois  et  meme  d'un  an,  elle  refuse  con- 
stamment  ses  caresses;  les  avances  empressees,  les  agaceries, 
les  tournoiemens,  les  tendres  roucoulemens,  rien  ne  pent  lui 
plaire  ni  Femouvoir ;  gonflee,  boudeuse,  blottie  dans  un 
coin  de  sa  prison,  elle  n'en  sort  que  pour  boire  et  manger, 
ou  pour  repousser  avec  une  espece  de  rage  des  caresses 
devenues  trop  pressantes.^^  *  On  the  other  hand,  Mr. 
Harrison  Weir  has  himself  observed  and  has  heard  from 
several  breeders,  that  a  female  pigeon  will  occasionally  take 
a  strong  fancy  for  a  particular  male,  and  will  desert  her 
own  mate  for  him.  Some  females,  according  to  another 
experienced  observer,  Riedel,t  are  of  a  profligate  disposi- 
tion, and  prefer  almost  any  stranger  to  their  own  mate. 
Some  amorous  males,  called  by  our  English  fanciers  "gay 
birds, '^  are  so  successful  in  their  gallantries  that,  as  Mr.  H. 
Weir  informs  me,  they  must  be  shut  up  on  account  of  the 
mischief  which  they  cause. 

Wild  turkeys  in  the  United  States,  according  to  Audu- 
bon, "  sometimes  pay  their  addresses  to  the  domesticated 
females,  and  are  generally  received  by  them  with  gi-eat 
pleasure. ''  So  that  these  females  apparently  prefer  the 
wild  to  their  own  males.  J 

Here  is  a  more  curious  case.  Sir  E.  Heron  during  many 
years  kept  an  account  of  the  habits  of  the  pea-fowl,  which 
he  bred  in  large  numbers.  He  states  that  '^  the  hens  have 
frequently  great  preference  to  a  particular  peacock.  They 
were  all  so  fond  of  an  old  pied  cock  that  one  year,  when  he 
was  confined,  though  still  in  view,  they  were  constantly 
assembled  close  to  the  trellised-walls  of  his  prison,  and  would 

♦Boitard  and  Corbie,  '* Les  Pigeons,  etc.,"  1824,  p.  12.  Prosper 
Lucas  ("Traite  de  I'Hered.  Nat.,"  torn,  ii,  1850,  p.  296)  has  himself 
observed  nearly  similar  facts  with  pigeons. 

t  "  Die  Taubenzucht,"  1824,  s.  86. 

J "  Ornithological  Biography,"  vol.  i,  p.  13.  See  to  the  same 
effect.  Dr.  Bryant,  in  *' 'Allen's  Mammals  and  Birds  of  Florida, "  d. 
344. 


476  1'tlE  DBSGRNT  OP  MAN. 

not  suffer  a  japanned  peacock  to  touch  them.  On  his  being 
let  out  in  the  autumn,  the  oldest  of  the  hens  instantly 
courted  him  and  was  successful  in  her  courtship.  The  next 
year  he  was  shut  up  in  a  stable,  and  then  the  hens  all 
courted  his  rivah"*  This  rival  was  a  japanned  or  black- 
winged  peacock,  to  our  eyes  a  more  beautiful  bird  than  the 
common  kind. 

Lichtenstein,  who  was  a  good  observer  and  had  excellent 
opportunities  of  observation  at  the  Cape  of  Good  Hope, 
assured  Rudolphi  that  the  female  widow -bird  (Chera 
progne)  disowns  the  male  wlien  robbed  of  the  long  tail 
feathers  with  which  he  is  ornamented  during  the  breeding- 
season.  I  presume  that  this  observation  must  have  been 
made  on  birds  under  confinement.!  Here  is  an  analogous 
case:  Dr.  Jaeger, J;  director  of  the  Zoological  Gardens  of 
Vienna,  states  that  a  male  silver-pheasant  who  had  been 
triumphant  over  all  other  males  and  was  the  accepted  lover 
of  the  females  had  his  ornamental  plumage  spoiled.  He 
was  then  immediately  superseded  by  a  rival  who  got  the 
upper  hand  and  afterward  led  the  flock. 

It  is  a  remarkable  fact,  as  showing  how  important  color 
is  in  the  courtship  of  birds,  that  Mr.  Boardman,  a  well- 
known  collector  and  observer  of  birds  for  many  years  in 
the  Northern  United  States,  has  never  in  his  large  experi- 
ence seen  an  albino  paired  with  another  bird;  yet  he  has 
had  opportunities  of  observing  many  albinos  belonging  to 
several  species.  §  It  can  hardly  be  maintained  that  albinos 
in  a  state  of  nature  are  incapable  of  breeding,  as  they  can 
be  raised  with  the  greatest  facility  under  confinement.  It 
appears,  therefore,  that  we  must  attribute  the  fact  that 
they  do  not  pair  to  their  rejection  by  their  normally  colored 
comrades. 

Female  birds  not  only  exert  a  choice,  but  in  some  few 

*"Proc.  Zool.  Soc. ,"  1835,  p.  54.  The  japanned  peacock  is  con- 
sidered by  Mr.  Sclater  as  a  distinct  species,  and  lias  been  named 
Pavo  nigripennis;  but  the  evidence  seems  to  me  to  show  that  it  is 
only  a  variety. 

f  Rudolphi,  "  Beytrage  ztir  Anthropologic, "  1812,  s.  184. 

I  "  Die  Darwin'sche  Theorie,  und  ihre  Stellung  zu  Moral  und 
Religion,"  1869,  s.  59. 

§This  statement  is  given  by  Mr.  A.  Leith  Adams,  in  his  "Field 
and  Forest  Rambles,"  1873,"  p.  76,  and  accords  with  his  own 
experience. 


BIRDS.  477 

cases  thev  court  the  male,  or  even  fight  together  for  liis 
possession.  Sir  R.  Heron  states  that  with  peafowl  the  first 
advances  are  always  made  by  the  female;  something  of  the 
same  kind  takes  place,  accoi'ding  ta  Audubon,  with  the 
older  females  of  the  wild  turkey.  With  the  capercailzie, 
the  females  flit  round  the  male  while  he  is  parading  at  one 
of  the  places  of  assemblage  and  solicit  his  attention.*  We 
have  seen  that  a  tame  wild  duck  seduced  an  unwilling  pin- 
tail drake  after  a  long  courtship.  Mr.  Bartlett  believes 
that  the  Lophophorus,  like  many  other  gallinaceous  birds, 
is  naturally  polygamous,  but  two  females  cannot  be  placed 
in  the  same  cage  with  a  males  as  they  fight  so  much 
together.  The  following  instance  of  rivalry  is  more  sur- 
prising as  it  relates  to  bullfinches,  which  usually  pair  for 
life.  Mr.  Jenner  AYeir  introduced  a  dull-colored  and  ugly 
female  into  his  aviary  and  she  immediately  attacked 
another  mated  female  so  unmercifully  that»  the  latter  had 
to  be  separated.  The  new  female  did  all  the  courtship, 
and  was  at  last  successful,  for  she  paired  with  the  male; 
but  after  a  time  she  met  with  a  just  retribution,  for,  ceas- 
ing to  be  pugnacious,  she  was  replaced  by  the  old  female, 
and  the  male  then  deserted  his  new  and  returned  to  his  old 
love. 

In  all  ordinary  cases  the  male  is  so  eager  that  he  will 
accept  any  female,  and  does  not,  as  far  as  we  can  judge, 
prefer  one  to  the  other ;  but,  as  we  shall  hereafter  see, 
exceptions  to  this  rule  apparently  occur  in  some  few 
groups.  With  domesticated  birds  I  have  heard  of  only  one 
case  of  males  showing  any  preference  for  certain  females, 
namely,  that  of  the  domestic  cock,  who,  according  to  the 
high  authority  of  Mr.  Hewitt,  prefers  the  younger  to  the 
older  hens.  On  the  other  hand,  in  effecting  hybrid  unions 
between  the  male  pheasant  and  common  hens,  Mr.  Hewitt  is 
convinced  that  the  pheasant  invariably  prefers  the  older 
birds.  He  does  not  appear  to  be  in  the  least  influenced  by 
their  color;  but  "is  most  capricious  in  his  attachments;"  f 
from  some  inexplicable  cause  he  shows  the  most  determined 

*In  regard  to  peafowl,  see  Sir  R.  Heron,  "  Proc.  Zoolog.  Soc.," 
1835,  p.  54,  and  the  Rev.  E.  S.  Dixon,  "  Ornamental  Poultry,"  1848, 
p.  8.  For  the  turkey,  Audubon,  ibid,  p.  4.  For  the  capercailzie, 
Lloyd,  "Game  Birds  of  Sweden,"  1867,  p.  23. 

fMr  Hewitt,  quoted  in  "Tegetmeier's  Poultry  Book."  1866,  p 
160. 


478  THM  DESCENT  OF  MAN, 

aversion  to  certain  hens,  which  no  care  on  the  part  of  the 
breeder  can  overcome.  Mr.  Hewitt  informs  me  that  some 
hens  are  quite  unattractive  even  to  the  males  of  their  own 
species,  so  that  they  may  be  kept  with  several  cocks  during 
a  whole  season,  and  not  one  Qgg  out  of  forty  or  fifty  will 
prove  fertile.  On  the  other  hand,  with  the  long-tailed 
duck  {Harelda  glacialis),  "  it  has  been  remarked,^'  says  M. 
Ekstrom,  ^^  that  certain  females  are  much  more  courted 
than  the  rest.  Frequently,  indeed,  one  sees  an  individual 
surrounded  by  six  or  eight  amorous  males."  Whether 
this  statement  is  credible,  I  know  not ;  but  the  native 
sportsmen  shoot  these  females  in  order  to  stuff  them  as 
decoys.* 

With  respect  to  female  birds  feeling  a  preference  for 
particular  males  we  must  bear  in  mind  that  we  can  judge 
of  choice  being  exerted  only  by  analogy.  If  an  inhabitant 
of  another  planet  were  to  behold  a  number  of  young 
rustics  at  a  fair  courting  a  pretty  girl  and  quarreling  about 
her,  like  birds  at  one  of  their  places  of  assemblage,  he 
would,  by  the  eagerness  of  the  wooers  to  please  her  and  to 
display  their  finery,  infer  that  she  had  the  power  of  choice. 
Now  with  birds  the  evidence  stands  thus;  they  have  acute 
powers  of  observation,  and  they  seem  to  have  some  taste 
for  the  beautiful  both  in  color  and  sound.  It  is  certain 
that  the  females  occasionally  exhibit,  from  unknown 
causes,  the  strongest  antipathies  and  preferences  for  par- 
ticular males.  When  the  sexes  differ  in  color  or  in  other 
ornaments  the  males  with  rare  exceptions  are  the  more 
decorated,  either  permanently  or  temporarily  during  the 
breeding-season.  They  sedulously  display  their  various 
ornaments,  exert  their  voices,  and  perform  strange  antics  in 
the  presence  of  the  females.  Even  well-armed  males,  who, 
it  might  be  thought,  would  altogether  depend  for  success 
on  the  law  of  battle,  are  in  most  cases  highly  ornamented  ; 
and  their  ornaments  have  been  acquired  at  the  expense  of 
some  loss  of  power.  In  other  cases  ornaments  have  been 
acquired  at  the  cost  of  increased  risk  from  birds  and  beasts 
of  prey.  With  various  species  many  individuals  of  both 
sexes  congregate  at  the  same  spot,  and  their  courtship  is  a 
prolonged  affair.  There  is  even  reason  to  suspect  that  the 
males  and  females  within  the  same  district  do  not  always 
succeed  in  pleasing  each  other  and  pairing. 

*  (Quoted  ii^  Lloyd's  "  Game  Birds  of  Sweden,"  p.  34^. 


BIRDS.  479 

What  then  are  we  to  conclude  from  these  facts  and  con- 
siderations? Does  the  male  parade  his  charms  with  so 
much  pomp  and  rivalry  for  no  purpose?  Are  we  not  justi- 
fied in  believing  that  the  female  exerts  a  choice,  and  that 
she  receives  the  addresses  of  the  male  who  pleases  her  most? 
It  is  not  probable  that  she  consciously  deliberates ;  but 
she  is  most  excited  or  attracted  by  the  most  beautiful,  or 
melodious,  or  gallant  males.  Nor  need  it  be  supposed  that 
the  female  studies  each  stripe  or  spot  of  color ;  that  the 
peahen,  for  instance,  admires  each  detail  in  the  gorgeous 
train  of  the  peacock — she  is  probably  struck  only  by  tlie 
general  effect.  Nevertheless,  after  hearing  how  carefully 
tlie  male  Argus  pheasant  displays  his  elegant  primary  wing- 
feathers  and  erects  his  ocellated  plumes  in  the  right  posi- 
tion for  their  full  effect;  or  again,  how  the  male  goldfinch 
alternately  displays  his  gold-bespangled  wings,  we  ought 
not  to  feel  too  sure  that  the  female  does  not  attend  to  each 
detail  of  beauty.  We  can  judge,  as  already  remarked,  of 
choice  being  exerted,  only  from  analogy;  and  the  mental 
powers  of  birds  do  not  differ  fundamentally  from  ours. 
From  these  various  considerations  we  may  conclude  that 
the  pairing  of  birds  is  not  left  to  chance;  but  that  those 
males,  which  are  best  able  by  their  various  charms  to  please 
or  excite  the  female,  are  under  ordinary  circumstances 
accepted.  If  this  be  admitted,  there  is  not  much  difficulty 
in  understanding  how  male  birds  have  gradually  acquired 
their  ornamental  characters.  All  animals  present  individ- 
ual differences,  and  as  man  can  modify  his  domesticated 
birds  by  selecting  the  individuals  which  appear  to  him  the 
most  beautiful,  so  the  habitual  or  even  occasional  preference 
by  the  female  of  the  more  attractive  males  would  almost 
certainly  lead  to  their  modification;  and  such  modifications 
might  in  the  course  of  time  be  augmented  to  almost  any 
extent,  compatible  with  the  existence  of  the  species. 

Variability  of  Birds,  a7id  Especially  of  TJieir  Secondary 
Sexual  Characters. — Variability  and  inheritance  are  the 
foundations  for  the  work  of  selection.  That  domesticated 
birds  have  varied  greatly,  their  variations  being  inherited, 
is  certain.  That  birds  in  a  state  of  nature  have  been  modi- 
fied into  distinct  races  is  now  universally  admitted.  *    Vari- 

*  According  to  Dr.  Blasius  ("  Ibis,"  vol.  ii,  1860,  p.  297),  there  are 
425  indubitable  species  of  birds  which  breed  in  Europe,  besides  sixty 


480  THE  DESCENT  OF  MAN 

ations  may  be  divided  into  two  classes;  those  which  appear 
to  our  ignorance  to  arise  spontaneously,  and  those  which  are 
directly  related  to  the  surrounding  conditions,  so  that  all  or 
nearly  all  the  individuals  of  the  same  species  are  similarly 
modified.  Cases  of  the  latter  kind  have  recently  been  observed 
with  care  by  Mr.  J.  A.  Allen,*  who  shows  that  in  the 
United  States  many  species  of  birds  gradually  become 
more  strongly  colored  in  proceeding  southward,  and  more 
lightly  colored  in  proceeding  westward  to  the  arid  plains 
of  the  interior.  Both  sexes  seem  generally  to  be  aHected 
in  a  like  manner,  but  sometimes  one  sex  more  than  the 
other.  Tliis  result  is  not  incompatible  with  the  belief  that 
the  colors  of  birds  are  maiidy  due  to  the  accumulation  of 
successive  variations  through  sexual  selection  ;  for  even 
after  the  sexes  have  been  greatly  differentiated,  climate 
might  produce  an  equal  effect  on  both  sexes,  or  a  greater 
effect  on  one  sex  than  on  the  other,  owing  to  some  consti- 
tutional difference. 

Individual  differences  between  the  members  of  the  same 
species  are  admitted  by  every  one  to  occur  under  a  state  of 
nature.     Sudden  and  strongly  marked  variations  are  rare  ; 

forms,  which  are  frequently  regarded  as  distinct  species.  Of  the 
latter,  Blasius  thinks  that  only  ten  are  really  doubtful  and  that  the 
other  fifty  ought  to  be  united  with  their  nearest  allies;  but  this 
shows  that  there  must  be  a  considerable  amount  of  variation  with 
some  of  our  European  birds.  It  is  also  an  unsettled  point  with 
naturalists,  whether  several  North  American  birds  ought  to  be 
ranked  as  specifically  distinct  from  the  corresponding  European 
species.  So  again  many  North  American  forms  which  until  lately 
were  named  as  distinct  species,  are  now  considered  to  be  local  races. 

*  "  Mammals  and  Birds  of  East  Florida,"  also  an  "  Ornithological 
Reconnaissance  of  Kansas,  etc."  Noth withstanding  the  influence  of 
climate  on  the  colors  of  birds,  it  is  difficult  to  account  for  the  dull  or 
dark  tints  of  almost  all  the  species  inhabiting  certain  countries,  for 
instance,  the  Galapagos  Islands  under  the  equator,  the  wide,  tem- 
perate plains  of  Patagonia,  and,  as  it  appears,  Egypt  (see  Mr.  Harts- 
horne  in  the  "American  Naturalist,"  1873,  p.  747).  These  countries 
are  open  and  afford  little  shelter  to  birds;  but  it  seems  doubtful 
whether  the  absence  of  brightly  colored  species  can  be  explained  on 
the  principle  of  protection,  for  on  the  Pampas,  which  are  equally 
open,  though  covered  by  green  grass,  and  where  the  birds  would  be 
equally  exposed  to  danger,  many  brilliant  and  conspicuously  colored 
species  are  common.  1  have  sometimes  speculated  whether  the  pre- 
vailing dull  tints  of  the  scenery  in  the  above-named  countries  may 
not  have  affected  the  appreciation  of  bright  colors  by  the  birds  inhab- 
iting them. 


BIRDS.  481 

it  is  also  doubtful  whether  if  beneficial  they  would  often  be 
preserved  through  selection  and  transmitted  to  succeeding 
generations.*  Nevertheless,  it  may  be  worth  while  to  give 
the  few  cases  which  I  have  been  able  to  collect,  relating 
chiefly  to  color — simple  albinism  and  melanism  being 
excluded.  Mr.  Gould  is  well  known  to  admit  the  exist- 
ence of  few  varieties,  for  he  esteems  very  slight  differences 
as  specific;  yet  he  statesf  that  near  Bogota  certain  hum- 
ming-birds belonging  to  the  genus  Cynanthus  are  divided 
into  two  or  three  races  or  varieties,  which  differ  from  each 
other  in  the  coloring  of  the  tail — ''  some  having  the  whole  of 
the  feathers  blue,  while  others  have  the  eight  central  ones 
tipped  with  beautiful  green.  ^'  It  does  not  appear  that 
intermediate  gradations  have  been  observed  in  this  or  the 
following  cases.  In  the  males  alone  of  one  of  the  Austra- 
lian paroquets  ^'  the  thighs  in  some  are  scarlet,  in  others 
grass-green."  In  another  paroquet  of  the  same  country 
''some  individuals  have  the  band  across  the  wing- coverts 
bright  yellow,  while  in  others  the  same  part  is  tinged  with 
red. "I  In  the  United  States  some  few  of  the  males  of  the 
Scarlet  Tanager  {Tanagra  rubra)  have  "a.  beautiful  trans- 
verse band  of  glowing  red  on  the  smaller  wing-coverts;"§ 
but  this  variation  seems  to  be  somewhat  rare,  so  that  its 
preservation  through  sexual  selection  would  follow  only 
under  unusually  favorable  circumstances.  In  Bengal  the 
honey  buzzard  {Pernis  cr  is  fata)  has  either  a  small  rudi- 

*"  Origin  of  Species."  5th  edit.,  1869,  p.  104.  I  had  always  per- 
ceived that  rare  and  strongly  marked  deviations  of  structure,  deserv- 
ing to  be  called  monstrosities,  could  seldom  be  preserved  through 
natural  selection,  and  that  the  preservation  of  even  highly  beneficial 
variations  would  depend  to  a  certain  extent  on  chance.  I  had  also 
fully  appreciated  the  importance  of  mere  individual  differences,  and 
this  led  me  to  insist  so  strongly  on  the  importance  of  that  unconscious 
form  of  selection  by  man  which  follows  from  tbe  preservation  of  the 
most  valued  individuals  of  each  breed,  without  any  intention  on  his 
part  to  modify  the  characters  of  the  breed.  But  until  I  read  an  able 
article  in  the  "  North  British  Review  "  (March,  1867,  p.  289,  et  seq.), 
which  has  been  of  more  use  to  me  than  any  other  review,  I  did  nut 
see  how  great  the  chances  were  against  the  preservation  of  variations, 
whether  slight  or  strongly  pronounced,  occurring  only  in  single 
individuals. 

f  •'  Introduct.  to  the  Trochilidae,"  p,  102. 

\  Gould,  "  Hand-book  to  Birds  of  Australia,"  vol.  ii,  pp.  32,  68. 

§  Audubon,  "Ornitholog.  Biography,"  1838,  vol.  iv,  p.  389. 


482  THE  DESCENT  OF  MAN, 

mental  crest  on  its  head,  or  none  at  all;  so  slight  a  differ- 
ence, however,  would  not  have  been  worth  notice,  had  not 
this  same  species  possessed  in  Soutliern  India  a  well-marked 
occipital  crest  formed  of  several  graduated  feathers/'* 

The  following  case  is  in  some  respects  more  interesting. 
A  pied  variety  of  the  raven,  with  the  head,  breast,  abdomen, 
and  parts  of  the  wings  and  tail-feathers  white  is  con- 
fined to  the  Feroe  Islands.  It  is  not  very  rare  there,  for 
Graba  saw  during  his  visit  from  eight  to  ten  living  speci- 
mens. Although  the  characters  of  this  variety  are  not 
quite  constant,  yet  it  has  been  named  by  several  distin- 
guished ornithologists  as  a  distinct  species.  The  fact  of 
the  pied  birds  being  pursued  and  persecuted  with  much 
clamor  by  the  other  ravens  of  the  island  was  the  chief 
cause  which  led  Briinnich  to  conclude  that  they  were 
specifically  distinct;  but  this  is  now  known  to  be  an  error.} 
This  case  seems  analogous  to  that  lately  given  of  albino 
birds  not  pairing  from  being  rejected  by  their  comrades. 

In  various  parts  of  the  northern  seas  a  remarkable  variety 
of  the  common  Guillemot  ( Uria  troile)  is  found;  and  in 
Feroe  one  out  of  every  five  birds,  according  to  Graba's  esti- 
mation, presents  this  variation.  It  is  characterized^  by  a 
pure  white  ring  round  the  eye,  with  a  curved  narrow  white 
line  an  inch  and  a  half  in  length  extending  back  from  the 
ring.  This  conspicuous  character  has  caused  the  bird  to 
be  ranked  by  several  ornithologists  as  a  distinct  species 
under  the  name  of  U.  lacrymans,  but  it  is  now  known  to 
be  merely  a  variety.  It  often  pairs  with  the  common  kind, 
yet  intermediate  gradations  have  never  been  seen;  nor  is 
this  surprising,  for  variations  which  appear  suddenly  are 
often,  as  I  have  elsewhere  shown, §  transmitted  either  unal- 
tered or  not  at  all.  We  thus  see  that  two  distinct  forms  of 
the  same  species  may  co-exist  in  the  same  district,  and  we 
cannot  doubt  that  if  the  one  had  possessed  any  advantage 

*Jerdon,  "Birds  of  India,"  vol,  i,  p.  108;  and  Mr.  Blytb,  in 
"  Land  and  Water,"  1868,  p.  381. 

f  Graba,  "Tagebucli  Reise  nacb  Faro,"  1830,  ss.  51-54.  Macgilli- 
vray,  "Hist.  British  Birds,"  vol.  iii,  p.  745.  "Ibis,"  vol.  v,  1863, 
p.  469. 

if  Graba,  ibid,  s.  54.     Macgillivray,  ibid,  vol.  v,  p.  327. 

§"  Variation  pf  Animals  and  Plants  un(Jer  Domestication,"  vol.  ii, 
p.  9^, 


BIRDS.  483 

over  the  other  it  would  soon  have  been  multiplied  to  the 
exclusion  of  the  latter.  If,  for  instance,  the  male  pied 
ravens,  instead  of  being  persecuted  by  their  comrades,  had 
been  highly  attractive  (like  the  above  pied  peacock)  to  the 
black  female  ravens  their  numbers  would  have  rapidly 
increased.  And  this  would  have  been  a  case  of  sexual 
selection. 

With  rpspect  to  the  slight  individual  differences  which 
are  common,  in  a  greater  or  less  degree,  to  all  the  mem- 
bers of  the  same  species,  we  have  every  reason  to  believe 
that  they  are  by  far  the  most  important  for  the  work  of 
selection.  Secondary  sexual  characters  are  eminently 
liable  to  vary,  both  with  animals  in  a  state  of  nature  and 
under  domestication.*  There  is  also  reason  to  believe,  as 
we  have  seen  in  our  eighth  chapter,  that  variations  are 
more  apt  to  occur  in  the  male  than  in  the  female  sex.  All 
these  contingencies  are  highly  favorable  for  sexual  selec- 
tion. Whether  characters  thus  acquired  are  transmitted  to 
one  sex  or  to  both  sexes  depends,  as  we  shall  see  in  the 
following  chapter,  on  the  form  of  inheritance  which 
prevails. 

It  is  sometimes  difficult  to  form  an  opinion  whether  cer- 
tain slight  differences  between  the  sexes  of  birds  are  simply 
the  result  of  variability  with  sexually  limited  inheritance 
without  the  aid  of  sexual  selection  or  whether  they  have 
been  augmented  through  this  latter  process.  I  do  not  here 
refer  to  the  many  instances  where  the  male  displays  splen- 
did colors  or  other  ornaments  of  which  the  female  partakes 
to  a  slight  degree;  for  these  are  almost  certainly  due  to 
characters  primarily  acquired  by  the  male  having  been 
more  or  less  transferred  to  the  female.  But  what  are  we  to 
conclude  with  respect  to  certain  birds  in  which,  for 
instance,  the  eyes  differ  slightly  in  color  in  the  two  sexes ?f 
In  some  cases  the  eyes  differ  conspicuously;  thus  with  the 
storks  of  the  genus  XenorhyncMis,  those  of  the  male  are 
blackish  -  hazel,  while  those  of  the  female  are  gamboge- 
yellow;  with  many  hornbills  (Buceros),  as  I  hear  from  Mr. 
Blyth,|  the  males  have  intense  crimson  eyes,  and  those  of 

*0n  these  points  see  also  "  Variation  of  Animals  and  Plants  under 
Domestication,"  vol.  i,  p.  253;  vol.  ii,  pp.  73,  75. 

■j-  See,  for  instance,  on  the  irides  of  a  Podica  and  Gallicrex  in 
"  Ibis,"  vol.  ii,  1860,  p,  206;  and  vol.  v.  1863,  p.  426. 

:}:See  also  Jerdon,  "  Birds  of  India,"  vol.  i,  pp.  243-245, 


484  TEE  DESCENT  OF  MAN, 

the  females  are  white.  In  the  Buceros  bicornis,  the  hind 
margin  of  the  casque  and  a  stripe  on  the  crest  of  the  beak 
are  black  in  the  male,  but  not  so  in  the  female.  Are  wo  to 
suppose  that  these  black  marks  and  the  crimson  color  of 
the  eyes  have  been  preserved  or  augmented  through  sexual 
selection  in  the  males?  This  is  very  doubtful;  for  Mr. 
Bartlett  showed  me  in  the  Zoological  Gardens  that  the 
inside  of  the  mouth  of  this  buceros  is  black  in  -the  male 
and  flesh -colored  in  the  female;  and  their  external  appear- 
ance or  beauty  would  not  be  thus  affected.  I  observed  in 
Chili  *  that  the  iris  in  the  condor,  when  about  a  year  old, 
is  dark -brown,  but  changes  at  maturity  into  a  yellowish- 
brown  in  the  male,  and  into  bright  red  in  the  female.  The 
male  has  also  a  small,  longitudinal,  leaden-colored,  fleshy 
crest  or  comb.  The  comb  of  many  gallinaceous  birds  is 
highly  ornamental,  and  assumes  vivid  colors  during  the  act 
of  courtship;  but  what  are  we  to  think  of  the  dull-colored 
comb  of  the  condor  which  does  not  appear  to  us  in  the  least 
ornamental?  The  same  question  may  be  asked  in  regard  to 
various  other  characters,  such  as  the  knob  on  the  base  of 
the  beak  of  the  Chinese  goose  (Anse?^  cygnoides),  which  is 
much  larger  in  the  male  than  in  the  female.  No  certain 
answer  can  be  given  to  these  questions;  but  we  ought  to  be 
cautious  in  assuming  that  knobs  and  various  fleshy  appen- 
dages cannot  be  attractive  to  the  female,  when  we  remem- 
ber that  with  savage  races  of  man  various  hideous 
deformities — deep  scars  on  the  face  with  the  flesh  raised 
into  protuberances,  the  septum  of  the  nose  pierced  by  sticks 
or  bones,  holes  in  the  ears  and  lips  stretched  widely  open — 
are  all  admired  as  ornamental. 

Whether  or  not  unimportant  differences  between  the 
sexes,  such  as  those  just  specified,  have  been  preserved 
through  sexual  selection,  these  differences,  as  well  as  all 
others,  must  primarily  depend  on  the  laws  of  variation.  On 
the  principle  of  correlated  development,  the  plumage  often 
varies  on  different  parts  of  the  body,  or  over  the  whole 
body,  in  the  same  manner.  We  see  this  well  illustrated  in 
certain  breeds  of  the  fowl.  In  all  the  breeds  the  feathers 
on  the  neck  and  loins  of  the  males  are  elongated  and  are 
called  hackles;  now  when  both  sexes  acquire  a  top-knot, 
which  is  a  new  character  in  the  genus,  the  feathers  on  the 

*  "  Zoology  of  the  Voyage  of  H,  M.  S.  '  Beagle,'  "  1841,  p.  6. 


BIRDS.  485 

head  of  the  male  become  hackle-shaped,  evidently  on  the 
principle  of  correlation;  while  those  on  the  head  of  the 
female  are  of  the  ordinary  sliape.  The  color  also  of 
the  hackles  forming  the  top-knot  of  the  male  is  often  cor- 
related with  that  of  the  hackles  on  the  neck  and  loins,  as 
may  be  seen  by  comparing  these  feathers  in  the  golden  and 
silver  -  spangled  Polish,  the  Houdans  and  Creve-cceur 
breeds.  In  some  natural  species  we  may  observe  exactly 
the  same  correlation  in  the  colors  of  these  same  feathers, 
as  in  the  males  of  the  splendid  gold  and  Amherst  pheasants. 

The  structure  of  each  individual  feather  generally  causes 
any  change  in  its  coloring  to  be  symmetrical;  we  see  this 
in  the  various  laced,  spangled,  and  penciled  breeds  of  the 
fowl;  and  on  the  principle  of  correlation  the  feathers  over 
the  whole  body  are  often  colored  in  the  same  manner.  We 
are  thus  enabled  without  much  trouble  to  rear  breeds  with 
their  plumage  marked  almost  as  symmetrically  as  in  natural 
species.  In  laced  and  spangled  fowls  the  colored  margins 
of  the  feathers  are  abruptly  defined  ;  but  in  a  mongrel 
raised  by  me  from  a  black  Spanish  cock  glossed  with  green, 
and  a  white  game-hen,  all  the  feathers  were  greenish-black, 
excepting  toward  their  extremities,  which  were  yellowish- 
white;  but  between  the  white  extremities  and  the  black 
bases  there  was  on  each  feather  a  symmetrical,  curved  zone 
of  dark -brown.  In  some  instances  the  shaft  of  the  feather 
determines  the  distribution  of  the  tints;  thus  with  the 
body-feathers  of  a  mongrel  from  the  same  black  Spanish 
cock  and  a  silver-spangled  Polish  hen,  the  shaft,  together 
with  a  narrow  space  on  each  side,  was  greenish-black,  and 
this  was  surrounded  by  a  regular  zone  of  dark-brown,  edged 
with  brownish-white.  In  these  cases  we  have  feathers 
symmetrically  shaded,  like  those  which  give  so  much  ele- 
gance to  the  plumage  of  many  natural  species.  I  have 
also  noticed  a  variety  of  the  common  pigeon  with  the  wing- 
bars  symmetrically  zoned  with  three  bright  shades,  instead 
of  being  simply  black  on  a  slaty-blue  ground,  as  in  the 
parent-species. 

In  many  groups  of  birds  the  plumage  is  differently  col- 
ored in  the  several  species,  yet  certain  spots,  marks,  or 
stripes  are  retained  by  all.  Analogous  cases  occur  with  the 
breeds  of  the  pigeon,  which  usually  retain  the  two  wing- 
bars,  though  they  may  be  colored  red,  yellow,  white,  black, 
or  blue,  the  rest  of  the  plumage  being  of  some  wholly  dif- 


480  THE  DESCENT  OF  MAN. 

ferent  tint.  Here  is  a  more  curious  case,  in  which  certain 
marks  are  retained,  though  colored  in  a  manner  almost 
exactly  the  opposite  of  what  is  natural ;  the  aboriginal 
pigeon  has  a  blue  tail,  with  the  terminal  halves  of  the  outer 
webs  of  the  two  outer  tail-feathers  white  ;  now  there 
is  a  sub  -  variety  having  a  white  instead  of  a  blue  tail, 
with  precisely  that  part  black  which  is  white  in  the  parent- 
species."* 

Formation  and  VariaUUty  of  the  Ocelli  or  Eye-Like 
Spots  071  the  Plumage  of  Birds. — As  no  ornaments  are 
more  beautiful  than  the  ocelli  on  the  feathers  of  various 
birds,  on  the  hairy  coats  of  some  mammals,  on  the  scales  of 
reptiles  and  fishes,  on  the  skin  of  amphibians,  on  the  wings 
of  many  Lepidoptera  and  other  insects,  they  deserve  to  be 
especially  noticed.  An  ocellus  consists  of  a  spot  within  a 
ring  of  another  color,  like  the  pupil  within  the  iris,  but 
the  central  spot  is  often  surrouded  by  additional  concentric 
zones.  The  ocelli  on  the  tail-coverts  of  the  peacock  offer 
a  familiar  example,  as  well  as  those  on  the  wings  of  the 
peacock-butterfly  (Vanessa).  Mr.  Trimen  has  given  me  a 
description  of  a  South  African  moth  (Gy?ianisa  isis), 
allied  to  our  emperor  moth,  in  which  a  magnificent  ocellus 
occupies  nearly  the  whole  surface  of  each  hinder  wing  ;  it 
consists  of  a  black  center,  including  a  semi-transparent 
crescent-shaped  mark,  surrounded  by  successive  ocher- 
yellow,  black,  ocher-yellow,  pink,  white,  pink,  brown  and 
whitish  zones.  Although  we  do  not  know  the  steps  by 
which  these  wonderfully  beautiful  and  complex  orna- 
ments liave  been  developed  the  process  has  probably  been  a 
simple  one,  at  least  with  insects;  for,  as  Mr.  Trimen  writes 
to  me,  "  no  characters  of  mere  marking  or  coloration  are 
so  unstable  in  the  Lepidoptera  as  the  ocelli,  both  in  number 
and  size."  Mr.  Wallace,  who  first  called  my  attention  to 
this  subject,  showed  me  a  series  of  specimens  of  our 
common  meadow-brown  butterfly  {Hipparchia  janira) 
exhibiting  numerous  gradations  from  a  simple  minute  black 
spot  to  an  elegantly  shaded  ocellus.  In  a  South  African 
butterfly  (C'yllo  leda,  Linn.),  belonging  to  the  same  family, 
the  ocelli  are  even  still  more  variable.     In  some  specimens 

•Bechstein,  "  Naturgeschicbte  Deutschlands,"  B.  iv,  1795,  s.  31, 
on  a  sub- variety  of  the  Monck  pigeon. 


BIHDS. 


487 


(a,  fig.  53)  large  spaces  on  the  upper  surface  of  the  wings 
are  colored  black,  and  include  irregular  white  marks;  and 
from  this  state  a  complete  gradation  can  be  traced  into  a 
tolerably  perfect  ocellus  («*),  and  this  results  from  the 
contraction  of  the  irregular  blotches  of  color.  In  another 
series  of  specimens  a  gradation  can  be  followed  from 
excessively  minute  white  dots,  surrounded  by  a  scarcely 
visible  black  line  (b),  into  perfectly  symmetrical  and  large 


Fig.  53.    Cyllo  leda,  Linn,  from  a  drawing  by  Mr.  Trimen,  showing  the  extreme 
range  of  variation  in  the  ocelli. 

a.  Specimen,  from  Mauritius,  upper     b.  Specimen,  from  Java,  upper  sur- 

surface  of  fore  wing.  face  of  hind  wing. 

a».  Specimen,  from  Natal,  ditto.  6*.  Specimen,  from  Mauritius,  ditto. 


ocelli  (Ji).*  In  cases  like  these,  the  development  of  a 
perfect  ocellus  does  not  require  a  long  course  of  variation 
and  selection. 

With  birds  and  many  other  animals  it  seems  to  follow 
from  the  comparison  of  allied  species  that  circular  spots 
are  often  generated  by  the  breaking  up  and  contraction  of 
stripes.    In  the  Tragopan  pheasant  faint  white  lines  in  the 

*This  wood-cut  has  been  engraved  from  a  beautiful  drawing,  most 
kindly  made  for  me  by  Mr.  Trimen;  see  also  liis  description  of  the 
wonderful  amount  of  variation  in  the  coloration  and  shape  of  the 
wings  of  this  butterfly,  in  his  "  Rhopalocera  Africfe  Australis,"  p. 
186. 


488  THE  DESCENT  OF  MAN. 

female  represent  the  beautiful  white  spots  in  the  male;* 
and  something  of  the  same  kind  may  be  observed  in  the 
two  sexes  of  the  Argus  pheasant.  However  this  may  be, 
appearances  strongly  favor  the  belief  that,  on  the  one  hand, 
a  dark  spot  is  often  formed  by  the  coloring  matter  being 
drawn  toward  a  central  point  from  a  surrounding  zone, 
which  latter  is  thus  rendered  lighter;  and,  on  the  other 
hand,  that  a  white  spot  is  often  formed  by  the  color  being 
driven  away  from  a  central  point,  so  that  it  accumulates  in 
a  surrounding  darker  zone.  In  either  case  an  ocellus  is  the 
result.  The  coloring  matter  seems  to  be  a  nearly  constant 
quantity,  but  is  redistributed,  either  centripetally  or  cen- 
trifugally.  The  feathers  of  the  common  guinea-fowl  offer 
a  good  instance  of  white  spots  surrounded  by  darker  zones; 
and  wherever  the  white  spots  are  large  and  stand  near  each 
other  the  surrounding  dark  zones  become  confluent.  In 
the  same  wing-feather  of  the  Argus  pheasant  dark  spots 
may  be  seen  surrounded  by  a  pale  zone  and  white  spots  by 
a  dark  zone.  Thus  the  formation  of  an  ocellus  in  its  most 
elementary  state  appears  to  be  a  simple  affair.  By  what 
further  steps  the  more  complex  ocelli,  which  are  surrounded 
by  many  successive  zones  of  color,  have  been  generated,  I 
will  not  pretend  to  say.  But  the  zoned  feathers  of  the 
mongrels  from  differently  colored  fowls,  and  the  extraor- 
dinary variability  of  the  ocelli  on  many  Lepidoptera,  lead 
us  to  conclude  that  their  formation  is  not  a  complex 
process,  but  depends  on  some  slight  and  graduated  change 
m  the  nature  of  the  adjoining  tissues. 

Gradation  of  Secondary  Sexual-  Cliaracters. — Cases  of 
gradation  are  important  as  showing  us  that  highly  complex 
ornaments  may  be  acquired  by  small  successive  steps.  In 
order  to  discover  the  actual  steps  by  which  the  male  of  any 
existing  bird  has  acquired  his  magnificent  colors  or  other 
ornaments  we  ought  to  behold  the  long  line  of  his  extinct 
progenitors;  but  this  is  obviously  impossible.  We  may, 
however,  generally  gain  a  clew  by  comparing  all  the  species 
of  the  same  group  if  it  be  a  large  one;  for  some  of  them 
will  probably  retain,  at  least  partially,  traces  of  their 
former  characters.  Instead  of  entering  on  tedious  details 
respecting  various  groups,  in  which   striking  instances  of 

*  Jerdon,  "  Birds  of  India,"  vol.  iii,  p.  517. 


BIRDS.  489 

gradation  could  be  given,  it  seems  the  best  plan  to  take 
one  or  two  strongly  marked  cases,  for  instance  that  of  the 
peacock,  in  order  to  see  if  light  can  be  thrown  on  the  steps 
by  which  this  bird  has  become  so  splendidly  decorated. 
The  peacock  is  chiefly  remarkable  from  the  extraordinary 
length  of  his  tail-coverts;  the  tail  itself  not  being  much 
elongated.  The  barbs  along  nearly  the  whole  length  of 
these  feathers  stand  separate  or  are  decomposed;  but  this 
is  the  case  with  the  feathers  of  many  species  and  with  some 
varieties  of  the  domestic  fowl  and  pigeon.  The  barbs 
coalesce  toward  the  extremity  of  the  shaft  forming  the 
oval  disk  or  ocellus,  which  is  certainly  one  of  the  most 
beautiful  objects  in  the  world.  It  consists  of  an  iridescent, 
intensely  blue,  indented  center,  surrounded  by  a  rich  green 
zone,  this  by  a  broad  coppery-brown  zone,  and  this  by  five 
other  narrow  zones  of  slightly  different  iridescent  shades. 
A  trifling  character  in  the  disk  deserves  notice;  the  barbs 
for  a  spa<?e  along  one  of  the  concentric  zones  are  more  or 
less  destitute  of  their  barbules,  so  that  a  part  of  the  disk  is 
surrounded  by  an  almost  transparent  zone,  which  gives  it  a 
highly  finished  aspect.  But  I  have  elsewhere  described* 
an  exactly  analogous  variation  in  the  hackles  of  a  sub- 
variety  of  the  gamecock  in  which  the  tips,  having  a  metallic 
luster,  "  are  separated  from  the  lower  part  of  the  feather 
by  a  symmetrically  shaped  transparent  zone  composed  of 
the  naked  portions  of  the  barbs."  The  lower  margin  or 
base  of  the  dark  blue  center  of  the  ocellus  is  deeply 
indented  on  the  line  of  the  shaft.  The  surrounding  zones 
likewise  show  traces,  as  may  be  seen  in  the  drawing  (fig. 
54),  of  indentations,  or  rather  breaks.  These  indentations 
are  common  to  the  Indian  and  Javan  peacocks  (Pavo 
cristatus  and  P.  muticus)  ;  and  they  seem  to  deserve 
particular  attention  as  probably  connected  with  the  devel- 
opment of  the  ocellus;  but  for  a  long  time  I  could  not 
conjecture  their  meaning. 

If  we  admit  the  principle  of  gradual  evolution  there 
must  formerly  have  existed  many  species  which  presented 
every  successive  step  between  the  wonderfully  elongated 
tail-coverts  of  the  peacock  and  the  short  tail-coverts  of  all 
ordinary  birds;  and  again  between  the  magnificent  ocelli 

*  "  Variation  of  Animals  and  Plants  under  Domestication,"  vol.  i, 
p.  254. 


490 


THE  DESCENT  OF  MAN. 


of  the  former  and  the  simpler  ocelli  or  mere  colored  spots 
on  other  birds;  and  so  with  all  the  other  characters  of  the 
peacock.  Let  us  look  to  the  allied  Gallinaceae  for  any  still- 
existing  gradations.  The  species  and  sub-species  of  Poly- 
plectron  inhabit  countries  adjacent  to  the  native  land  of  the 
peacock;  and  they  so  far  resemble  this  bird  that  they  are 
sometimes  called  peacock-pheasants.     I  am  also  informed 


Fig.  54.  Feather  of  peacock,  about  two-thirds  of  natural  size,  drawn  by  Mr. 
Ford.  The  transparent  zone  is  represented  by  the  outermost  white  zone, 
confined  to  the  upper  end  of  the  disk. 


by  Mr.  Bartlett  that  they  resemble  the  peacock  in  their 
voice  and  in  some  of  their  habits.  During  the  spring  the 
males,  as  previously  described,  strut  about  before  the  com- 
paratively plain-colored  females,  expanding  and  erecting 
their  tail  and  wing  feathers,  which  are  ornamented  with 
numerous  ocelli.  I  request  tlie  reader  to  turn  back  to  the 
drawing  (fig.  51)  of  a  Polyplectron.  In  P.  napoleonis 
the  ocelli  are  confined  to  the  tail,  and  the  back  is  of  a  rich 


BIRDS.  491 

metallic  blue;  in  which  respects  this  species  approaches  the 
Java  peacock.  P.  hardunckii  possesses  a  peculiar  top-knot, 
which  is  also  somewhat  like  that  of  the  Java  peacock.  In 
all  the  species  the  ocelli  on  the  wings  and  tail  are  either 
circular  are  oval,  and  consist  of  a  beautiful,  iridescent, 
greenish-blue  or  greenish-purple  disk  with  a  black  border. 
This  border  in  P.  chinquis  shades  into  brown,  edged  with 
cream  color,  so  that  the  ocellus  is  here  surrounded  with 
variously  shaded,  though  not  bright,  concentric  zones. 
The  unusual  length  of  the  tail-coverts  is  another  remark- 
able character  in  Polyplectron;  for  in  some  of  the  species 
they  are  half  and  in  others  two- thirds  as  long  as  the  true 
tail  feathers.  The  tail-coverts  are  ocellated  as  in  the 
peacock.  Thus  the  several  species  of  Polyplectron  mani- 
festly make  a  graduated  approach  to  the  peacock  in  the 
length  of  their  tail-coverts,  in  the  zoning  of  the  ocelli,  and 
in  some  other  characters. 

Notwithstanding  this  approach,  the  first  species  of  Poly- 
plectron which  I  examined  almost  made  me  give  up  the 
search;  for  I  found  not  only  that  the  true  tail-coverts,  which 
in  the  peacock  are  quite  plain,  were  ornamented  with  ocelli, 
but  that  the  ocelli  on  all  the  feathers  differed  fundament- 
ally from  those  of  the  peacock,  in  there  being  two  on  the 
same  feather  (fig.  55),  one  on  each  side  of  the  shaft. 
Hence  I  concluded  that  the  early  progenitors  of  the  pea- 
cock could  not  have  resembled  a  Polyplectron.  But  on 
continuing  my  search  I  observed  that  in  some  of  the  spe- 
cies the  two  ocelli  stood  very  near  each  other;  that  in  the 
tail-feathers  of  P.  hardioickii  they  touched  each  other ; 
and  finally  that  on  the  tail-coverts  of  this  same  species  as 
Avell  as  of  P.  malaccense  (fig.  56)  they  were  actually  con- 
fluent. As  the  central  part  alone  is  confluent,  an  indenta- 
tion is  left  at  both  the  upper  and  lower  ends;  and  the  sur- 
rounding colored  zones  are  likewise  indented.  A  single 
ocellus  is  thus  formed  on  each  tail-covert,  though  still 
plainly  betraying  its  double  origin.  These  confluent  ocelli 
differ  from  the  single  ocelli  of  the  peacock  in  having  an 
indentation  at  both  ends  instead  of  only  at  the  lower  or 
basal  end.  The  explanation,  however,  of  this  difference  is 
not  difficult;  in  some  species  of  Polyplectron  the  two  oval 
ocelli  on  the  same  feather  stand  parallel  to  each  other;  in 
other  species  (as  in  P.  chinquis)  they  converge  toward  one 
end;  now  the  partial  confluence  of  two  convergent  ocelli 


492  THE  DESCENT  OF  MAN. 

would  manifestly  leave  a  much  deeper  indentation  at  the 
divergent  than  at  the  convergent  end.  It  is  also  manifest 
that  if  the  convergence  were  strongly  pronounced  and  the 
confluence  complete,  the  indentation  at  the  convergent  end 
would  tend  to  disappear. 

The  tail-feathers  in  both  species  of  the  peacock  are  en- 
tirely destitute  of  ocelli,  and  this  apparently  is  related  to 
their  being  covered  up  and  concealed  by  the  long  tail- 
coverts.     In  this  respect  they  differ  remarkably  from  the 


Fig.  55.    Part  of  a  tail-covert  of  Poly-       Fig.  56.    Part  of  a  tale-covert  of  Poly- 
plectron   chinquis,  with   the    two  plectron  malaccense,  with  the  two 

ocelli  of  natural  size.  ocelli,  partially  confluent,  of  nat- 

ural size. 

tail-feathers  of  Polyplectron,  which  in  most  of  the  species 
are  ornamented  with  larger  ocelli  than  those  on  the  tail- 
coverts.  Hence  I  was  led  carefully  to  examine  the  tail- 
feathers  of  the  several  species,  in  order  to  discover  whether 
their  ocelli  showed  any  tendency  to  disiippear;  and  to  my 
great  satisfaction  this  appeared  to  be  so.  The  central  tail- 
feathers  of  P.  napoleonis  have  the  two  ocelli  on  each  side 
of  the  shaft  perfectly  developed;  but  the  inner  ocellus  be- 
comes less  and  less  conspicuous  on  the  more  exterior  tail- 
feathers,  until  a  mere  shadow  or  rudiment  is  left  on  the 
inner  side  of  the  outermost  feather.     Again,  in  P.  malac- 


BIRDS.  493 

cense,  the  ocelli  on  tlie  tail-coverts  are,  as  we  have  seen, 
confluent;  and  these  feathers  are  of  unusual  length,  being 
two-tliirds  of  the  length  of  the  tail-feathers,  so  that  in  both 
these  respects  they  approach  the  tail -coverts  of  the  peacock. 
Now  in  P.  malaccense  the  two  central  tail-feathers  alone 
are  ornamented,  each  with  two  brightly  colored  ocelli,  the 
inner  occellus  having  completely  disappeared  from  all  the 
other  tail-feathers.  Consequently  the  tail-coverts  and  tail- 
feathers  of  this  species  of  Polyplectron  make  a  near  approach 
in  structure  and  ornamentation  to  the  corresponding  feathers 
of  the  peacock. 

As  far,  then,  as  gradation  throws  light  on  the  steps  by 
which  the  magnificent  train  of  the  peacock  has  been 
acquired,  hardly  anything  more  is  needed.  If  we  picture 
to  ourselves  a  progenitor  of  the  peacock  in  an  almost 
exactly  intermediate  condition  between  the  existing  peacock 
with  his  enormously  elongated  tail-coverts  ornamented  with 
single  ocelli,  and  an  ordinary  gallinaceous  bird  with  short 
tail-coverts  merely  spotted  with  some  color,  we  shall  see  a 
bird  allied  to  Polyplectron — that  is,  with  tail-coverts  capable 
of  erection  and  expansion,  ornamented  with  two  partially 
confluent  ocelli,  and  long  enough  almost  to  conceal  the 
tail-feathers,  the  latter  having  already  partially  lost  their 
ocelli.  The  indentation  of  the  central  disk  and  of  the 
surrounding  zones  of  the  ocellus  in  both  species  of  peacock 
speaks  plainly  in  favor  of  this  view  and  is  otherwise  inexpli- 
cable. The  males  of  the  Polyplectron  are  no  doubt  beautiful 
birds,  but  their  beauty,  when  viewed  from  a  little  distance, 
cannot  be  compared  with  that  of  the  peacock.  Many  female 
progenitors  of  the  peacock  must,  during  a  long  line  of 
descent,  have  appreciated  this  superiority;  for  they  have 
unconsciously,  by  the  continued  preference  of  the  most 
beautiful  males,  rendered  the  peacock  the  most  splendid 
of  living  birds. 

Argus  Pheasant. — Another  excellent  case  for  investiga- 
tion is  offered  by  the  ocelli  on  the  wing-feathers  of  the 
Argus  pheasant,  which  are  shaded  in  so  wonderful  a 
manner  as  to  resemble  balls  lying  loose  within  sockets  and 
consequently  differ  from  ordinary  ocelli.  No  one,  I  pre- 
sume, will  attribute  the  shading,  which  has  excited  the 
admiration  of  many  experienced  artists,  to  chance — to  the 
fortuitous  concourse  of  atoms  of  coloring  matter.     That 


494 


THE  DESCENT  OF  MAN, 


these  ornaments  should  have  been  formed  throngli  the  selec- 
tion of  many  successive  variations,  not  one  of  which  was 
originally  intended  to  produce  the  ball-and-socket  effect, 
seems  as  incredible  Jis  that  one  of  RaplieaFs  Madonnas 
should  have  been  formed  by  the  selection  of  chance  daubs 

of  paint  made  by  a  long 
ABC  succession  of  young  art- 
ists, not  one  of  whom 
intended  at  first  to  draw 
the  human  figure.  In 
order  to  discover  liow 
the  ocelli  have  been 
developed  we  cannot 
look  to  a  long  line  of 
progenitors  nor  to  many 
closely  allied  forms,  for 
such  do  not  now  exist. 
But  fortunately  the 
several  feathers  on  the 
wing  suffice  to  give  us 
a  clew  to  the  problem, 
and  they  prove  to  dem- 
onstration that  a  gra- 
dation is  at  lojist  pos- 
sible from  a  mere  spot 
to  a  finished  ball-and- 
socket  ocellus. 

The  wing  -  feathers, 
bearing  the  ocelli,  are 
covered  with  dark 
stripes  (fig.  57)  or 
with  rows  of  dark  six)ts 
(fig.  59),  each  stripe  or 
'     of     ^ 

the 
outer  side  of  the  shaft 

to'the  left  of  the  shaft,  has  been  cut  oSr  *  ^   ^O    OUC    of     the    OCclH. 

The  spots  are  gen- 
erally elongated  in  a  line  transverse  to  the  row  in  which 
they  stand.  They  often  become  confluent  either  in  the  line 
of  the  row — and  then  they  form  a  longitudinal  stripe — or 
transversely,  that  is,  with  the  spots  in  the  adjoining  rows, 
and  then  they  form  transverse  stripes.     A  spot  sometimes 


Flff.  57.    Part  o{  secondary  winpr-feather  of  „„.„    ^e    K\\f\i& 

Arjfus  pheasant,  showing  two  perfect  ocelli,  ^'^'"     '^'^    ^ptno 

a  and  6.    A,  B,  C,  D,  etc.,  are  dark  stripes  obllQUelv       down 
running  obliquely  down,  each  to  an  ocellus.  *     -  - 


4d$ 


pkct«. 
U  will  W  t?c«iT«n5(?wt  fiirt^t  tt>  d<(N»*riK> »  wrfiH^lt  btJl-^mtil- 

ti  ball*     Tlu»  fi^\m»  h<or\»  jjiwu  h»s  Wmimi  ti<i)ii)imb)y  dmwn 
by  Mr*  Fi>rvl  »iul  wt^l  <i>n- 
^mvtHl*    but    »    wwi*l-out 

Tho  rinjr  i^  abmie^t  tuwH\TS 


iHUut  iu  Ok>  x\\>Vk^t  half  ti 


hIh^w  Uii»  whiU»  s^h»((l<^  MU 
i\\K^  \\\<Avt^'^\  IMi  it  ii^  ^\i^ 
mnw  tim(o*st  bn4^M4  Um»r\l 
ilu»  lKiift5^>  v>«  i\w  rijjht  hauxL 
Th©i!*»  liUb*  bnmi*  haw  an 
iiu(M>»Haut  m^Hiuiik^.  Th<@^ 
riug  ifei  tilwaw  muoli  thiok- 
^MUHi»  with  i\\<c  <e<\^^  ill- 
doftiunl  tt>wanl  i\w  ^<ch- 
hiiiwl    u|i»^H*r   iHJirn^r*    tW 

tho  jHv<itivm  iu  vl%iioh  it  isi 
hon^  ilrawu*  )K^Uv*aih  this 
thioktMunl  |.)«rt  tlu^rt?  it*  ou 
i\w  «iu  r  faiMi*  ^^f  the  IhU  I  au  kA>- 
limu\  ttluu>«tt  pua»  whito  u^ark  whidi  i^xaub^  c^tf  dc^wwwartil 
iuU>  ti  ii*iK^K>atU*n  luu\  aud  tbist  iuto  ^^^lhl•wi5^l^  aiul  lm>wu 
tiutfts  wfuoh  iu8«n»ut4hl\  lMtH\>uu>ilarki^ralul  <ilark<er  t<t>warvl  tbi* 
Kuwvr  i»art  i^t  i\w  li«lL  It  is*  tbi^  ^htmliu^  which  giv*?)?  m 
aibuirahlv  tlu»  i>l(rwt  t>f  %ht  i^uuiu^  m\  a  \\>uvt>x  i^urfaw. 
If  wuv  ixf  tb<i>  luallji  bj>  oxauumnl  it  will  W  sinni  that  thi* 
lowwr  juart  i»  \>t  ti  br\>wu  tiut  ami  iis^  imlii^tiuctlv  !»*^^»ratt(Mil 
by  a  curviHl  t>blimu^  liuo  txmn  tho  ww^^t  mtU  wluoh  i»  ytvl- 
lowi^r  aiul  uu>rt*  l<ea^bnu  thi**  eurvinl  obtitjud*  liut*  ruui?  at 
ri^ht  tn\^U^  t^»  i\w  UMujti^r  axi«  <>(  the  whit^^  [vntoh  <4  li^ht> 
aud  iuvUnnl  of  all  the  lAtmliu^^.  but  tbi^  ditb>nouw  iu  wlw» 
whioh  oauuot  «f  iHUirw  W  jvlumu  iu  tho  w((M¥[lH*ut>  ttl<i¥(>i!s  wnA 
m  i\w  bHi»t  iuterlvjr^  with  the  ^R>rfc<?t  »l\adiug  <4  tb<?  hmlh 


490  TIIK  DKSCRNT  OF  MAN. 

It  Hhould  be  particularly  ohHcrvod  tliat  oadi  ocoIIur  HtandH 
in  obviouH  coniioctioii  eitlior  with  a  (lari<  Htri{)(!  or  witli  a 
longitudinal  row  of  dark  HpotH,  for  })oth  wa'axy  indifTorentiy 


on  tlie  Hanio  feather.  'I'Iiuh  in  fig.  57  Htrine  A  ruiiH  to 
ocelluH  a;  B  runK  to  oeelliiH  h;  Htripe  C  iH  broken  in  the 
npper  part  and  riniH  down  to  the  next  Huoeeeding  oeellus, 
not  represented  in  the  wood-eiit;  I)  to  the  next  lower  one, 
and  m  with  the  HtripeH  E  and  F.  LaHtly  the  Hev(;ral  oeelli 
are  senarated  from  each  other  by  a  pale  surface  bearing 
irregular  black  ma-rkH. 

I  will  next  dencribe  the  other  extreme  of  the  series, 
namely,  the  first  trace  of  an  ocellus.  Tin;  short  secondary 
wing-ieather  (fig.  58),  nearest  to  the  body,  is  markcid  like 
tlie  other  featliers,  with  oblique;,  longitudinal,  rath(;r  irn^g- 
ular  rows  of  very  dark  sf)otH.  TIhj  basal  spot,  or  that  n(;ar- 
est  the  shaft  in  the  five  lower  rows  (excluding  the  low(;st 
one),  is  a  little  larger  than  the  other  st)ots  of  the  same  row, 
and  a  little  more  elongated  in  a  transverse  direction.  It 
differs  also  from  th(;  other  spots  by  being  bordered  on  its 
upper  side  witli  some  dull  fulvous  shading.  liut  this  spot 
is  not  in  any  way  more  remarkable  than  those  on  the  plum- 
age of  many  birds,  and   might  easily  be  overlooked.     'J'he 

at  all 


next  higher  spot  do(!s  not  differ  at  all  from  the  upper  ones 
in  the  same  row.  The  larger  basal  spots  ocenipy  exactly 
the  same  relative  position  on  these  feathers  as  do  the  per- 


\\y  looking  to  the  next  two  or  three  succeeding  wing- 
feathers,  an  absolutely  insensible  gradation  can  be  traced 
from  one  of  the  last  described  basal  spots,  together  with  the 
next  higher  one  in  the  same  row,  to  a  curious  ornament, 
which  (;annot  be  called  an  ocellus,  and  which  J  will  name, 
from  the  want  of  a  better  term,  an  "ellii)tic  ornament." 
These  are  shown  in  the  accompanying  figure  (fig.  59).  We 
here  see  several  oblioue  rows.  A,  ft,  (',  I),  etc.  (see  the  let- 
tered diagram  on  tne  right  hand),  of  dark  spots  of  the 
usual  character.  Each  row  of  sj)ots  runs  down  to  and  is 
connected  with  one  of  the  elliptic  ornaments,  in  exactly 
the  same  manner  as  each  stripe  in  fig.  57  runs  down  to, 
and  is  connected  with,  one  of  the  ball-and-socket  o(;elli. 
Looking  to  any  one  row,  for  instance,  Ji,  in  fig.  51),  the 
lowest  mark  (h)  is  thicker  and  considerably  longer  than  the 
upper  spots,  and  has  its  left  extremity  pointed  and  curved 
upward,    Thie  black  mark  is  abruptly  bordered  on  its 


BIRDS. 


491 


upp«r  side  by  a  rather  broad  space  of  richly  shaded  tints, 
beginning  with  a  narrow  brown  zone,  which  passes  into 
orange,  and  this  into  a  pale  leaden  tint,  with  the  end  toward 
the  shaft  much  paler.  These  shaded  tints  together  fill  np 
the  whole  inner  space  of  the  elliptic  ornament.     The  mark 


^- 


¥ig.  50.  Portion  of  one  of  the  seoondarr  wine-feathers  near  the  body,  showing 
the  so-called  elliptic  ornaments.  Tne  ri^t-hand  figure  is  given  merely  as 
a  diagram  for  the  sake  of  the  letters  of  reference. 

A,  B,  C.  D,  etc.    Bows  of  qwts  mnning  down  to  and  framing  the  elliptic 


b.  Lowest  spot  or  mavlE  in  row  B. 

c.  "Hie  next  succeeding  spot  or  marie  in  the  same  row. 

d.  Anwrently  a  broken  prolongation  of  the  spot  C  in  the  same  row  B. 

(h)  corresponds  in  eyery  respect  with  the  basal  shaded  spot 
of  the  simple  feather  described  in  the  last  paragraph  (fig. 
58),  but  is  more  highly  developed  and  more  brightly  col- 
ored. Above  and  to  the  right  of  this  spot  (b  fig.  59),*  with 
its  bright  shading,  there  is  a  long,  narrow,  black  mark  (c), 
belonging  to  the  same  row,  and  which  is  arched  a  little 
downward  so  as  to  face  (b).  This  mark  is  sometimes  broken 
into  two  portions.  It  is  also  narrowly  edged  on  the  lower 
side  with  a  fulvous  tint.  To  the  left  of  and  above  (c),  in 
the  same  oblique  direction,  but  always  more  or  less  distinct 


498  tii^  i)^8(JBNT  OF  MAN, 

from  it,  there  is  another  biack  mark  (d).  ^Phis  matk  is 
generally  sub-triangular  and  irregular  in  shape,  but  in  the 
one  lettered  in  the  diagram  it  is  unusually  narrow,  elon- 
gated and  regular.  It  apparently  consists  of  a  lateral  and 
broken  prolongation  of  the  mark  (c),  together  with  its  con- 
fluence with  a  broken  and  prolonged  part  of  the  next  spot 
above;  but  I  do  not  feel  sure  of  this.  These  three  marks, 
(b),  (c)  and  (d),  with  the  intervening  bright  shades,  form 
together  the  so-called  elliptic  ornament.  These  ornaments 
placed  parallel  to  the  shaft,  manifestly  correspond  in  posi- 
tion with  the  ball-and-socket  ocelli.  Their  extremely  ele- 
gant appearance  cannot  be  appreciated  in  th3  drawing,  as 
the  orange  and  leaden  tints,  contrasting  so  well  with  the 
black  marks,  cannot  be  shown. 

Between  one  of  the  elliptic  ornaments  and  a  perfect 
ball-and-socket  ocellus  the  gradation  is  so  perfect  that  it  is 
scarcely  possible  to  decide  when  the  latter  term  ought  to  be 
used.  The  passage  irom  the  one  into  the  other  is  effected 
by  the  elongation  and  greater  curvature  in  the  opposite 
directions  of  the  lower  black  mark  (b  fig.  59),  and  more 
especially  of  the  upper  one  (6'),  together  with  the  contrac- 
tion of  the  elongated  sub-triangular  or  narrow  mark  (d),  so 
that  at  last  these  three  marks  become  confluent,  forming  an 
irregular  elliptic  ring.  This  ring  is  gradually  rendered 
more  and  more  circular  and  regular,  increasing  at  the  same 
time  in  diameter.  I  have  here  given  a  drawing  (fig.  60)  of 
the  natural  size  of  an  ocellus  not  as  yet  quite  perfect. 
The  lower  part  of  the  black  ring  is  much  more  curved  than  is 
the  lower  mark  in  the  elliptic  ornament  (b  fig.  59).  The 
upper  part  of  the  ring  consists  of  two  or  three  separate 
portions;  and  there  is  only  a  trace  of  the  thickening  of  the 
portion  which  forms  the  black  mark  above  the  white  shade. 
This  white  shade  itself  is  not  as  yet  much  concentrated; 
and  beneath  it  the  surface  is  brighter  colored  than  in  a  per- 
fect ball-and-socket  ocellus.  Even  in  the  most  perfect 
ocelli  traces  of  the  junction  of  three  or  four  elongated 
black  marks,  by  which  the  ring  has  been  formed,  may  often 
be  detected.  The  irregular  sub-triangular  or  narrow  mark 
(d  fig.  59),  manifestly  forms,  by  its  contraction  and  equal- 
ization, the  thickened  portion  of  the  ring  above  the  white 
shade  on  a  perfect  ball-and-socket  ocellus.  The  lower  part 
of  the  ring  is  invariably  a  little  thicker  than  the  other 
parts  (see  fig.  57),  and  this  follows  from  the  lower  black 


BIRDS, 


499 


mark  of  the  elliptic  ornament  {h  fig.  59)  having  originally 
been  thicker  than  the  upper  mark  (c).  Every  stej)  can  be 
followed  in  the  process  of  confluence  and  modifirntioi-i:  and 
the  black  ring  which  sur- 
rounds the  ball  of  the  ocellus 
is  unquestionably  formed  by 
the  union  and  modification 
of  the  three  black  marks,  h,  c, 
d,  of  the  elliptic  ornament. 
The  irregular  zigzag  black 
marks  between  the  successive 


Fig.  60. 


ig.  ei. 


Fig.  60.  An  ocellus  in  an  intermedate  condition  between  the  elliptic  ornament 
and  the  perfect  ball-and-socket  ocellus. 

Fig.  t>l.  Portion  near  summit  of  one  of  the  secondary  wing-feathers,  bearing 
perfett  ball-and-socket  ocelli,  a.  Ornamented  upper  part.  b.  Uppermost, 
imperfect  ball-and-socket  ocellus.  (The  shading  above  the  white  mark  on 
the  summit  of  the  ocellus  is  here  a  little  too  dark.)    c.  Perfect  ocellus. 


ocelli  (see  again  fig.  57)  are  plainly  due  to  the  breaking  up 
of  the  somewhat  more  regular  but  similar  marks  between 
the  elliptic  ornaments. 

The  successive  steps  in  the  shading  of  the  ball-and- 
socket  ocelli  can  be  followed  out  with  equal  clearness. 
The  brown,  orange  and  pale-leadened  narrow  zones  which 
border  the  lower  black  mark  of  the  elliptic  ornament  can 


500  THE  DESCENT  OF  MAN. 

be  seen  gradually  to  become  more  and  more  softened  and 
shaded  into  each  other,  with  the  upper  lighter  part  toward 
the  left-hand  corner  rendered  still  lighter,  so  as  to  become 
almost  white  and  at  the  same  time  more  contracted.  But 
even  in  the  most  perfect  ball-and-socket  ocelli  a  slight  dif- 
ference in  the  tints,  though  not  in  the  shading,  between 
the  upper  and  lower  parts  of  the  ball  can  be  perceived,  as 
before  noticed;  and  the  line  of  separation  is  oblique  in  the 
same  direction  as  the  bright-colored  shades  of  the  elliptic 
ornaments.  Thus  almost  every  minute  detail  in  the  shape 
and  coloring  of  the  ball-and-socket  ocelli  can  be  shown  to 
follow  from  gradual  changes  in  the  elliptic  ornaments;  and 
the  development  of  the  latter  can  be  traced  by  equally 
small  steps  from  the  union  of  two  almost  simple  spots,  the 
lower  one  (fig.  58)  having  some  dull  fulvous  shading  on  its 
upper  side. 

The  extremities  of  the  longer  secondary  feathers  which 
bear  the  perfect  ball-and-socket  ocelli  are  peculiarly  orna- 
mented (fig.  61).  The  oblique  longitudinal  stripes  sud- 
denly cease  upward  and  become  confused;  and  above  this 
limit  the  whole  upper  end  of  the  feather  {a)  is  covered 
with  white  dots  surrounded  by  little  black  rings  standing 
on  a  dark  ground.  The  oblique  stripe  belonging  to  the 
uppermost  ocellus  {h)  is  barely  represented  by  a  very  short 
irregular  black  mark  with  the  usual  curved,  transverse 
base.  As  this  stripe  is  thus  abruptly  cut  off  we  can  per- 
haps understand  from  what  has  gone  before  how  it  is  that 
the  upper  thickened  part  of  the  ring  is  here  absent;  for,  as 
before  stated,  this  thickened  part  apparently  stands  in 
some  relation  with  a  broken  prolongation  from  the  next 
higher  spot.  From  the  absence  of  the  upper  and  thickened 
part  of  the  ring  the  uppermost  ocellus,  though  perfect  in 
all  other  respects,  appears  as  if  its  top  had  been  obliquely 
sliced  off.  It  would,  I  think,  perplex  any  one  who  believes 
that  the  plumage  of  the  Argus  pheasant  was  created  as  we 
now  see  it  to  account  for  the  imperfect  condition  of  the 
uppermost  ocellus.  I  should  add  that  on  the  secondary 
wing-feather  farthest  from  the  body  all  the  ocelli  are 
smaller  and  less  perfect  than  on  the  other  feathers  and 
have  the  upper  part  of  the  ring  deficient,  as  in  the  case 
just  mentioned.  The  imperfection  here  seems  to  be  con- 
nected with  the  fact  that  the  spots  on  this  feather  show 
less  tendency  than  usual  to  become  confluent  into  stripesj 


SlRBS.  501 

they  are,  on  tlie  contrary,  often  broken  up  into  smaller 
spots,  so  that  two  or  three  rows  run  down  to  the  same 
ocellus. 

There  still  remains  another  very  curious  point,  first 
observed  by  Mr.  T.  W.  Wood,*  which  deserves  attention. 
In  a  photograph,  given  me  by  Mr.  Ward,  of  a  specimen 
mounted  as  in  the  act  of  display,  it  may  be  seen  that  on  the 
feathers  which  are  held  perpendicularly,  the  white  marks 
on  the  ocelli,  representing  light  reflected  from  a  convex 
surface,  are  at  the  upper  or  farther  end,  that  is,  are  directed 
upward;  and  the  bird  while  displaying  himself  on  the 
ground  would  naturally  be  illuminated  from  above.  But 
^here  comes  the  curious  point,  the  outer  feathers  are  held 
almost  horizontall}^,  and  their  ocelli  ought  likewise  to 
appear  as  if  illuminated  from  above,  and  consequently  the 
white  marks  ought  to  be  placed  on  the  upper  sides  of  the 
ocelli;  and,  wonderful  as  is  the  fact,  they  are  thus  placed! 
Hence  the  ocelli  on  the  several  feathers,  though  occupying 
very  different  positions  with  respect  to  the  light,  all  appear 
as  if  illuminated  from  above,  just  as  an  artist  would  have 
shaded  them.  Nevertheless  they  are  not  illuminated  from 
strictly  the  same  point  as  they  ought  to  be;  for  the  white 
marks  on  the  ocelli  of  the  feathers,  which  are  held  almost 
horizontally,  are  placed  rather  too  much  toward  the  farther 
end;  that  is,  they  are  not  sufficiently  lateral.  We  have, 
however,  no  right  to  expect  absolute  perfection  in  a  part 
rendered  ornamental  through  sexual  selection,  any  more 
than  we  have  in  a  part  modified  through  natural  selection 
for  real  use;  for  instance,  in  that  wondrous  organ  the 
human  eye.  And  we  know  what  Helmholtz,  the  highest 
authority  in  Europe  on  the  subject,  has  said  about  the 
human  eye,  that  if  an  optician  had  sold  him  an  instrument 
so  carelessly  made,  he  would  have  thought  himself  fully 
justified  in  returning  it.  f 

We  have  now  seen  that  a  perfect  series  can  be  followed, 
from  simple  spots  to  the  wonderful  ball-and-socket  orna- 
ments. Mr.  Gould,  who  kindly  gave  me  some  of  these 
feathers,  fully  agrees  with  me  in  the  completeness  of  the 
gradation.     It  is  obvious  that  the  stages  in  development 

*TLe  "  Field,"  May  28,  1870. 

f  "  Popular  Lectures  on  Scientific  Subjects,"  Eng.  trans.,  1873,  pp. 
219,  227,  269.  390. 


502  TBE  DBBGEMf  OF  MAif. 

exhibited  by  the  feathers  on  the  same  bird  do  not  at  all 
necessarily  show  us  the  steps  passed  through  by  the  extinct 
progenitors  of  the  species;  but  they  probably  give  us  the 
clue  to  the  actual  steps,  and  they  at  last  prove  to  demon- 
stration that  a  gradation  is  possible.  Bearing  in  mind  how 
carefully  the  male  Argus  pheasant  displays  his  plumes 
before  the  female,  as  well  as  the  many  facts  rendering  it 
probable  that  female  birds  prefer  the  more  attractive  males, 
no  one  who  admits  the  agency  of  sexual  selection  in  any 
case  will  deny  that  a  simple  dark  spot  with  some  fulvous 
shading  might  be  converted,  through  the  approximation 
and  modification  of  two  adjoining  spots,  together  with 
some  slight  increase  of  color,  into  one  of  the  so-called  ellip- 
tic ornaments.  These  latter  ornaments  have  been  shown 
to  many  persons,  and  all  have  admitted  that  they  are  beau- 
tiful, some  thinking  them  even  more  so  than  the  ball-and- 
socket  ocelli.  As  the  secondary  plumes  became  lengthened 
through  sexual  selection,  and  as  the  elliptic  ornaments 
increased  in  diameter,  their  colors  apparently  became  less 
bright;  and  then  the  ornamentation  of  the  plumes  had  to 
be  gained  by  an  improvement  in  the  pattern  and  shading ; 
and  this  process  was  carried  on  until  the  wonderful  ball- 
and-socket  ocelli  were  finally  developed.  Thus  we  can 
understand — and  in  no  other  way  as  it  seems  to  me — the 
present  condition  and  origin  of  the  ornaments  on  the 
wing-feathers  of  the  Argus  pheasant. 

From  the  light  afforded  by  the  principle  of  gradation — 
from  what  we  know  of  the  laws  of  variation — from  the 
changes  which  have  taken  place  in  many  of  our  domesti- 
cated birds — and,  lastly,  from  the  character  (as  we  shall 
hereafter  see  more  clearly)  of  the  immature  plumage  of 
young  birds — we  can  sometimes  indicate,  with  a  certain 
amount  of  confidence,  the  probable  steps  by  which  the 
males  have  acquired  their  brilliant  plumage  and  various 
ornaments;  yet  in  many  cases  we  are  involved  in  complete 
darkness.  Mr.  Gould  several  years  ago  pointed  out  to  me 
a  humming-bird,  the  Urosticte  benjamini,  remarkable  for 
the  curious  differences  between  the  sexes.  The  male, 
besides  a  splendid  gorget,  has  greenish-black  tail-feathers 
with  the  four  central  ones  tipped  with  white;  in  the  female, 
as  with  most  of  the  allied  species,  the  three  outer  tail- 
feathers  on  either  side  are  tipped  with  white^  so  that  the 


BIRDS.  503 

male  has  four  central,  while  the  female  has  the  six  exterior 
feathers  ornamented  with  white  tips.  What  makes  the 
case  more  curious  is  that,  although  the  coloring  in  the  tail 
differs  remarkably  in  both  sexes  of  many  kinds  of  hum- 
ming-birds, Mr.  Grould  does  not  know  a  single  species, 
besides  the  Urosticte,  in  which  the  male  has  the  four  central 
feathers  tipped  with  white. 

The  Duke  of  Argyll,  in  commenting  on  this  case,* 
passes  over  sexual  selection,  and  asks:  **  What  explanation 
does  the  law  of  natural  selection  give  of  such  specific 
varieties  as  these  ?'*'  He  answers  "none  whatever;"  and  I 
quite  agree  with  him.  But  can  this  be  so  confidently 
said  of  sexual  selection  ?  Seeing  in  how  many  ways  the 
tail-feathers  of  humming-birds  differ,  why  should  not 
the  four  central  feathers  have  varied  in  this  one  species  alone, 
so  as  to  have  acquired  white  tips  ?  The  variations  may 
have  been  gradual  or  somewhat  abrapt,  as  in  tlie  case 
recently  given  of  the  humming-birds  near  Bogota,  in  which 
certain  individuals  alone  have  the  "  central  tail-feathers 
tipped  with  beautiful  green."  In  the  female  of  the  Urosticte 
I  noticed  extremely  minute  or  rudimental  white  tips  to  the 
two  outer  of  the  four  central  black  tail-feathers;  so  that 
here  we  have  an  indication  of  change  of  some  kind  in  the 
plumage  of  this  species.  If  we  grant  the  possibility  of  the 
central  tail  feathers  of  the  male  varying  in  whiteness,  there 
is  nothing  strange  in  such  variations  having  been  sexually 
selected.  The  white  tips,  together  with  the  small  white 
ear-tuffs,  certainly  add,  as  the  Duke  of  Argyll  admits,  to 
the  beauty  of  the  male ;  and  whiteness  is  apparently  appre- 
cited  by  other  birds,  as  may  be  inferred  from  such  cases  as 
the  snow-white  male  of  the  bell-bird.  The  statement  made 
by  Sir  R.  Heron  should  not  be  forge tten,  namely,  that  his 
peahens,  when  debarred  from  access  to  the  pied  peacock, 
would  not  unite  with  any  other  male,  and  during  that  season 
produced  no  offspring.  Nor  is  it  strange  that  variations  in 
the  tail-feathers  of  the  Urosticte  should  have  been  specially 
selected  for  the  sake  of  ornament,  for  the  next  succeeding 
genus  in  the  family  takes  its  name  of  Metallura  from  the 
splendor  of  these  feathers.  AVe  liave,  moreover,  good 
evidence  that  Iiumming-birds  take  especial   pains  in  dis- 

*"  The  Reign  of  Law,"  1867,  p.  247. 


§04  ^^^  DESCENT  OF  MAN. 

playing  their  tail-feathers;  Mr.  Belt,*  after  describing  the 
beauty  of  the  Florisuga  mellivora,  says:  "  I  have  seen  the 
female  sitting  on  a  branch  and  two  males  displaying  their 
charms  in  front  of  her.  One  would  shoot  up  like  a  rocket, 
then,  suddenly  expanding  the  snow-white  tail,  like  an 
inverted  parachute,  slowly  descend  in  front  of  her,  turning 
round  gradually  to  show  off  back  and  front.  .  .  .  The 
expanded  white  tail  covered  more  space  than  all  the  rest  of 
the  bird,  and  was  evidently  the  grand  feature  in  the  per- 
formance. While  one  male  was  descending  the  other 
would  shoot  up  and  come  slowly  down  expanded.  The 
entertainment  would  end  in  a  fight  between  the  two  per- 
formers; but  whether  the  most  beautiful  or  the  most  pugna- 
cious was  the  accepted  suitor,  I  know  not.^"*  Mr.  Gould, 
after  describing  the  peculiar  plumage  of  the  Urosticte, 
adds,  ^'  that  ornament  and  variety  is  the  sole  object,  I  have 
myself  but  little  doubt. "f  If  this  be  admitted,  we  can  per- 
ceive that  the  males  which  during  former  times  were 
decked  in  the  most  elegant  and  novel  manner  would  have 
gained  an  advantage,  not  in  the  ordinary  struggle  for  life, 
but  in  rivalry  with  other  males,  and  would  have  left  a 
larger  number  of  offspring  to  inherit  their  newly  acquired 
beauty. 

*  "The  Naturalist  in  Nicaragua,"  1874,  p.  112. 
f  "Introduction  to  the  Trochilidae,"  1861,  p.  110. 


BIRD8.  605 


CHAPTER   XV. 

BIRDS — continued. 

Discussion  as  to  why  the  males  alone  of  some  species,  and  both  sexes 
of  others,  are  brightly  colored — On  sexually  limited  inheritance, 
as  applied  to  various  structures  and  to  brightly  colored  plumage 
— Nidification  in  relation  to  color — Loss  of  nuptial  plumage  dur- 
ing the  winter. 

We  have  in  this  chapter  to  consider  why  the  females  of 
many  birds  have  not  acquired  the  same  ornaments  as  the 
male;  and  why,  on  the  other  hand,  both  sexes  of  many 
other  birds  are  equally,  or  almost  equally,  ornamented?  In 
the  following  chapter  we  shall  consider  the  few  cases 
in  which  the  female  is  more  conspicuously  colored  than  the 
male. 

In  my  "Origin  of  Species"*  I  briefly  suggested  that 
the  long  tail  of  the  peacock  would  be  inconvenient  and  the 
conspicuous  black  color  of  the  male  capercailzie  dangerous 
to  the  female  during  the  period  of  incubation;  and  conse- 
quently that  the  transmission  of  these  characters  from  the 
male  to  the  female  offspring  had  been  checked  througli 
natural  selection.  I  still  think  that  this  may  have  occurred 
in  some  few  instances;  but  after  mature  reflection  on  all 
the  facts  which  I  have  been  able  to  collect,  I  am  now 
inclined  to  believe  that  when  the  eexes  differ  the  successive 
variations  have  generally  been  from  the  first  limited  in 
their  transmission  to  the  same  sex  in  which  they  first 
arose.  Since  my  remarks  appeared  the  subject  of  sexual 
coloration  has  been  discussed  in  some  very  interesting 
papers  by  Mr.  Wallace,!  who  believes  that  in  almost  all 
cases  the  successive  variations  tended  at  first  to  be  trans- 
mitted equally  to  both  sexes;  but  that  the  female  was  saved, 

♦Fourth  edition,  1866,  p.  241. 

f  "  Westminster  Review,"  July,  1867.  "Journal  of  Travel,"  vol. 
i,  1868,  p.  73. 


506  'THE  DESCENT  OF  MAK. 

through  natural  selection,  from  acquiring  the  conspicuous 
colors  of  the  male,  owing  to  the  danger  which  she  would 
thus  have  incurred  during  incubation. 

This  view  necessitates  a  tedious  discussion  on  a  difficult 
point,  namely,  whether  the  transmission  of  a  character 
which  is  at  first  inherited  by  both  sexes  can  be  subsequently 
limited  in  its  transmission  to  one  sex  alone  by  means  of 
natural  selection.  We  must  bear  in  mind,  as  shown  in  the 
preliminary  chapter  on  sexual  selection,  that  characters 
which  are  limited  in  tlieir  development  to  one  sex  are 
always  latent  in  the  other.  An  imaginary  illustration  will 
best  aid  us  in  seeing  the  difficulty  of  the  case;  we  may  sup- 
pose that  a  fancier  wished  to  make  a  breed  of  pigeons,  in 
which  the  males  alone  should  be  colored  of  a  pale  blue, 
while  the  females  retained  their  former  slaty  tint.  As  with 
pigeons  characters  of  all  kinds  are  usually  transmitted  to 
both  sexes  equally,  the  fancier  would  have  to  try  to  convert 
this  latter  form  of  inheritance  into  sexually  limited  trans- 
mission. All  that  he  could  do  would  be  to  persevere  in 
selecting  every  male  pigeon  which  was  in  the  least  degree 
of  a  paler  blue;  and  the  natural  result  of  this  process,  if 
steadily  carried  on  for  a  long  time,  and  if  the  pale  varia- 
tions were  strongly  inherited  or  often  recurred,  would  be 
to  make  his  whole  stock  of  a  lighter  blue.  But  our  fancier 
would  be  compelled  to  match,  generation  after  generation, 
his  pale-blue  males  with  slaty  females,  for  he  wishes  to  keep 
the  latter  of  this  color.  The  result  would  generally  be  the 
production  either  of  a  mongrel  piebald  lot,  or  more  prob- 
ably the  speedy  and  complete  loss  of  the  pale-blue  tint;  for 
the  primordial  slaty  color  would  be  transmitted  with  pre- 
potent force.  Supposing,  however,  that  some  pale-blue 
males  and  slaty  females  were  produced  during  each  succes- 
sive generation,  and  were  always  crossed  together,  then  the 
slaty  females  would  have,  if  I  may  use  the  expression,  much 
blue  blood  in  their  veins,  for  their  fathers,  grandfathers, 
etc.,  will  all  have  been  blue  birds.  Under  these  circum- 
stances it  is  conceivable  (though  I  know  of  no  distinct  facts 
rendering  it  probable)  that  the  slaty  females  might  acquire 
so  strong  a  latent  tendency  to  pale-blueness  that  they  would 
not  destroy  this  color  in  their  male  offspring,  their  female 
offspring  still  inheriting  tlie  slaty  tint.  If  so,  the  desired 
end  of  making  a  breed  with  the  two  sexes  permanently  dif- 
ferent in  color  might  be  gained. 


BIRDS,  bOi 

The  extreme  importance,  or  rather  necessity,  in  the 
above  case  of  the  desired  character,  namely,  pale-bhieness, 
being  present  though  in  a  latent  state  in  the  female,  so  that 
the  male  offspring  should  not  be  deteriorated,  will  be  best 
appreciated  as  follows:  the  male  of  Soemmerring's  pheasant 
has  a  tale  thirty-seven  inches  in  length,  while  that  of  the 
female  is  only  eight  inches;  the  tale  of  the  male  common 
pheasant  is  about  twenty  inches,  and  that  of  the  female 
twelve  inches  long.  Now  if  the  female  Scemmerring  pheas- 
ant with  her  sliort  tail  were  crossed  with  the  male  common 
pheasant  there  can  be  no  doubt  that  the  male  hybrid  off- 
spring would  have  a  much  longer  tail  than  that  of  the  pure 
offspring  of  the  common  pheasant.  On  the  other  hand,  if 
the  female  common  pheasant,  with  a  tail  much  longer  than 
that  of  the  female  Scemmerring  pheasant,  were  crossed  with 
the  male  of  the  latter,  the  male  hybrid  offspring  would 
have  a  much  sliorter  tail  than  that  of  the  pure  offspring  of 
Soemmerring's  pheasant.  * 

Our  fancier,  in  order  to  make  his  new  breed  with  the 
males  of  a  pale-blue  tint,  and  the  females  unchanged, 
would  have  to  continue  selecting  the  males  during  many 
generations;  and  each  stage  of  paleness  would  have  to  be 
fixed  in  the  males,  and  rendered  latent  in  the  females.  The 
task  would  be  an  extremely  difficult  one,  and  has  never 
been  tried,  but  might  possibly  be  successfully  carried  out. 
The  chief  obstacle  would  be  the  early  and  complete  loss  of 
the  pale-blue  tint,  from  the  necessity  of  reiterated  crosses 
Avith  the  slaty  female,  the  latter  not  having  at  first  any 
latent  tendency  to  produce  pale-blue  offspring. 

On  the  other  hand,  if  one  or  two  males  were  to  vary  ever 
so  slightly  in  paleness,  and  the  variations  were  from  the 
first  limited  in  their  transmission  to  the  male  sex,  the  task 
of  making  a  new  breed  of  the  desired  kind  would  be  easy, 
for  such  males  would  simply  have  to  be  selected  and 
matched  with  ordinary  females.  An  analogous  case  has 
actually  occurred,  for  there  are  breeds  of  the  pigeon  in 
Belgium  \  in  which  the  males  alone  are  marked  with  black 

*  Temminck  says  tliat  the  tail  of  the  female  Plumanus  Scmimer- 
ringii  is  only  six  inches  long,  "  Planches  coloriees,"  vol.  v,  1838,  pp. 
487,  488;  the  measurements  above  given  were  made  for  me  by  Mr. 
Sclater.  For  the  common  pheasant,  see  Macgillivray,  "Hist.  Brit. 
Birds,"  vol.  i,  pp.  118-121. 

f  Dr.  Chapius,  *'  Le  Pigeon  Voyageur  Beige,"  1865,  p.  87. 


50B  THE  DESCENT  OF  MAN. 

striae.  So  again  Mr.  Tegetmeier  has  recently  shown  *  that 
dragons  not  rarely  produce  silver-colored  birds,  which  are 
almost  always  hens;  and  he  himself  has  bred  ten  such 
females.  It  is  on  the  other  hand  a  very  unusual  event 
when  a  silver  male  is  produced;  so  that  nothing  would  be 
easier,  if  desired,  than  to  make  a  breed  of  dragons  with 
blue  males  and  silver  females.  This  tendency  is  indeed  so 
strong  that  when  Mr.  Tegetmeier  at  last  got  a  silver  male 
and  matched  liim  with  one  cf  the  silver  females  he 
expected  to  get  a  breed  with  both  sexes  thus  colored ;  he 
was,  however,  disappointed,  for  the  young  male  reverted  to 
the  blue  color  of  his  grandfather,  the  youn^  female  alone 
being  silver.  No  doubt  with  patience  this  tendency  to 
reversion  in  the  males,  reared  from  an  occasional  silver  male 
matched  with  a  silver  hen,  might  be  eliminated,  and  then 
both  sexes  would  be  colored  alike;  and  this  very  process  has 
been  followed  with  success  by  Mr.  Esquilant  in  the  case  of 
silver  turbits. 

AVith  fowls,  variations  of  color,  limited  in  their  trans- 
mission to  the  male  sex,  habitually  occur.  When  this  form 
of  inheritance  prevails  it  might  well  happen  that  some  of 
the  successive  variations  would  be  transferred  to  the  female, 
who  would  then  slightly  resemble  the  male,  as  actually 
occurs  in  some  breeds.  Or  again,  the  greater  number,  but 
not  all,  of  the  successive  steps  might  be  transferred  to  both 
sexes,  and  the  female  would  then  closely  resemble  the 
male.  There  can  hardly  be  a  doubt  that  this  is  the  cause 
of  the  male  pouter  pigeon  having  a  somewhat  larger  crop, 
and  of  the  male  carrier  pigeon  having  somewhat  larger 
wattles  than  their  respective  females ;  for  fanciers  have 
not  selected  one  sex  more  than  the  other,  and  have  had  no 
wish  that  these  characters  should  be  more  strongly  dis- 
played in  the  male  than  in  the  female,  yet  this  is  the  case 
with  both  breeds. 

The  same  process  would  have  to  be  followed  and  the 
same  difficulties  encountered  if  it  were  desired  to  make  a 
breed  with  the  females  alone  of  some  new  color. 

Lastly,  our  fancier  might  wish  to  make  a  breed  with  the 
two  sexes  differing  from  each  other,  and  both  from  the 
parent  species.  Here  the  difficulty  would  be  extreme 
unless  the  successive  variations  were  from  the  first  sexually 

*"  The  Field,"  Sept.,  1872. 


BIBBS.  509 

limited  on  both  sides,  and  then  there  would  be  no  diffi- 
culty. Wc  see  this  with  the  fowl;  thus  the  two  sexes  of 
the  penciled  Hamburghs  differ  greatly  from  each  other, 
and  from  the  two  sexes  of  the  aboriginal  Gallus  bankiva; 
and  both  are  now  kept  constant  to  their  standard  of  excel- 
lence by  continued  selection  which  would  be  impossible 
unless  the  distinctive  characters  of  both  were  limited  in 
their  transmission. 

The  Spanish  fowl  offers  a  more  curious  case;  the  male 
has  an  immense  comb,  but  some  of  the  successive  varia- 
tions, by  the  accumulation  of  which  it  was  acquired,  appear 
to  have  been  transferred  to  the  female;  for  she  has  a  comb 
many  times  larger  than  that  of  the  females  of  the  parent 
species.  But  the  comb  of  the  female  differs  in  one  respect, 
from  that  of  the  male,  for  it  is  apt  to  lop  over;  and  within  a. 
recent  period  it  has  been  ordered  by  the  fancy  that  this 
should  always  be  the  case,  and  success  has  quickly  followed 
the  order.  N"ow  the  lopping  of  the  comb  must  be  sexually 
limited  in  its  transmission,  otherwise  it  would  prevent  the 
comb  of  the  male  from  being  perfectly  upright,  which 
would  be  abhorrent  to  every  fancier.  On  the  other  hand, 
the  uprightness  of  the  comb  in  the  male  must  likewise  be 
a  sexually  limited  character,  otherwise  it  would  prevent  the 
comb  of  the  female  from  lopping  over. 

From  the  foregoing  illustrations  we  see  that  even  with 
almost  unlimited  time  at  command  it  would  be  an  ex- 
tremely difficult  and  complex,  perhaps  an  impossible  pro- 
cess, to  change  one  form  of  transmission  into  the  other 
through  selection.  Therefore,  without  distinct  evidence 
in  each  case,  I  am  unwilling  to  admit  that  this  has  been 
effected  in  natural  species.  On  the  other  hand,  by  means 
of  successive  variations,  which  were  from  the  first  sexually 
limited  in  their  transmission,  there  would  not  be  the  least 
difficulty  in  rendering  a  male  bird  widely  different  in  color 
or  in  any  other  character  from  the  female;  the  latter  being 
left  unaltered,  or  slightly  altered,  or  specially  modified  for 
the  sake  of  protection. 

As  bright  colors  are  of  service  to  the  males  in  their 
rivalry  with  other  males,  such  colors  would  be  selected 
whether  or  not  they  were  transmitted  exclusively  to  the 
same  sex.  Consequently  the  females  might  be  expected 
often  to  partake  of  the  brightness  of  the  males  to  a  greater 
or  less  degree;  and  this  occurs  with  a  host  of  species. 


510  THE  DESCENT  OF  MAN. 

If  all  the  successive  variations  were  transmitted  equally 
to  both  sexes  the  females  would  be  indistinguishable  from 
the  males  ;  and  this  likewise  occurs  with  many  birds. 
If,  however,  dull  colors  were  of  high  importance  for  the 
safety  of  the  female  during  incubation,  as  with  many 
ground  birds,  the  females  which  varied  in  brightness 
or  which  received  through  inheritance  from  the  males 
any  marked  accession  of  brightness  would  sooner  or  later 
be  destroyed.  But  the  tendency  in  the  males  to  continue 
for  an  indefinite  period  transmitting  to  their  female  off- 
spring their  own  brightness,  would  have  to  be  eliminated 
by  a  change  in  the  form  of  inheritance;  and  this,  as  shown 
by  our  previous  illustration,  would  be  extremely  difficult. 
The  more  probable  result  of  the  long-continued  destruc- 
tion of  the  more  brightly  colored  females,  supposing  tlie 
equal  form  of  transmission  to  prevail,  would  be  the  lessen- 
ing or  annihilation  of  the  bright  colors  of  the  males, 
owing  to  their  continual  crossing  with  the  duller  females. 
It  would  be  tedious  to  follow  out  all  the  other  possible 
results;  but  I  may  remind  the  reader  that  if  sexually  lim- 
ited variations  in  brightness  occurred  in  the  females,  even 
if  they  were  not  in  the  least  injurious  to  them  and  conse- 
quently were  not  eliminated,  yet  they  would  not  be  favored 
or  selected,  for  the  male  usually  accepts  any  female,  and 
does  not  select  the  more  attractive  individuals ;  conse- 
quently these  variations  would  be  liable  to  be  lost,  and 
would  have  little  influence  on  the  character  of  the  race;  and 
this  will  aid  in  accounting  for  the  females  being  commonly 
duller-colored  than  the  males. 

In  the  eighth  chapter  instances  were  given,  to  which 
many  might  here  be  added,  of  variations  occurring  at  vari- 
ous ages  and  inherited  at  the  corresponding  age.  It  was 
also  shown  that  variations  which  occur  late  in  life  are  com- 
monly transmitted  to  the  same  sex  in  which  they  first 
appear;  while  variations  occurring  early  in  life  are  apt  to 
be  transmitted  to  both  sexes;  not  that  all  the  cases  of  sexu- 
ally limited  transmission  can  thus  be  accounted  for.  It 
was  further  shown  that  if  a  male  bird  varied  by  becoming 
brighter  while  young,  such  variations  would  be  of  no  ser- 
vice until  the  age  for  reproduction  had  arrived,  and  there 
was  competition  between  rival  males.  But  in  the  case  of 
birds  living  on  the  ground  and  commonly  in  need  of  the 
protection  of  dull  colors^  bright   tints  would  be  far  more 


BIRDS.  511 

dangerous  to  the  young  and  inexperienced  than  to  the 
adult  males.  Consequently  the  males  which  varied  in 
brightness  while  young  would  suffer  much  destruction  and 
be  eliminated  through  natural  selection;  on  the  other  hand, 
the  males  which  varied  in  this  manner  when  nearly  mature, 
notwithstanding  that  they  were  exposed  to  some  additional 
danger,  might  survive,  and,  from  being  favored  through 
sexual  selection,  would  procreate  their  kind.  As  a  relation 
often  exists  between  the  period  of  variation  and  the  form 
of  transmission,  if  the  bright-colored  young  males  were 
destroyed  and  the  mature  ones  were  successful  in  their 
courtship,  the  males  alone  would  acquire  brilliant  colors 
and  would  transmit  them  exclusively  to  their  male  off- 
spring. But  I  by  no  means  wish  to  maintain  that  the 
influence  of  age  on  the  form  of  transmission  is  the  sole 
cause  of  the  great  difference  in  brilliancy  between  the 
sexes  of  many  birds. 

When  the  sexes  of  birds  differ  in  color  it  is  interesting 
to  determine  whether  the  males  alone  have  been  modified 
by  sexual  selection,  the  females  having  been  left  unchanged 
or  only  partially  and  indirectly  thus  changed;  or  whether 
the  females  have  been  specially  modified  through  natural 
selection  for  the  sake  of  protection.  I  will,  therefore,  dis- 
cuss this  question  at  length,  even  more  fully  than  its  intrin- 
sic importance  deserves ;  for  various  curious  collateral 
points  may  thus  be  conveniently  considered. 

Before  we  enter  on  the  subject  of  color,  more  especially 
in  reference  to  Mr.  Wallace's  conclusions,  it  may  be 
useful  to  discuss  some  other  sexual  differences  under  a  similar 
point  of  view.  A  breed  of  fowls  formerly  existed  in  Ger- 
many *  in  which  the  hens  were  furnished  with  spurs;  they 
were  good  layers,  but  they  so  greatly  disturbed  their  nests 
with  their  spurs  that  they  could  not  be  allowed  to  sit  on 
their  own  eggs.  Hence  at  one  time  it  appeared  to  me 
probable  that  with  the  females  of  the  wild  Gallinaceae  the 
development  of  spurs  had  been  checked  through  natural 
selection  from  the  injury  thus  caused  to  their  nests.  This 
seemed  all  the  more  probable,  as  wing-spurs,  which  would 
not  be  injurious  during  incubation,  are  often  as  well 
developed  in  the  female  as  in  the  male;  though  in  not  a 

*3echstein,  "  JJ^atur^esch.  Deutscklands,"  1793,  B.  iii,  s.  339, 


512  THE  DESCENT  OF  MAN. 

few  cases  they  are  rather  larger  in  the  male.  When  the 
male  is  furnished  with  leg-spurs  the  female  almost  always 
exhibits  rudiments  of  them — the  rudiment  sometimes  con- 
sisting of  a  mere  scale,  as  in  Gallus.  Hence  it  might  be 
argued  that  the  females  had  aboriginally  been  furnished 
with  well-developed  spurs,  but  that  these  had  subsequently 
been  lost  through  disuse  or  natural  selection.  But  if  this 
view  be  admitted  it  would  have  to  be  extended  to  innumer- 
able other  cases;  and  it  implies  that  the  female  progenitors 
of  the  existing  spur-bearing  species  were  once  incumbered 
with  an  injurious  appendage. 

In  some  few  genera  and  species,  as  in  Galloperdix, 
Acomus  and  the  Javan  peacock  {Pavo  muticus),  the 
females,  as  well  as  the  males,  possess  well-developed  leg- 
spurs.  Are  we  to  infer  from  this  fact  that  they  construct 
a  different  sort  of  nest  from  that  made  by  their  nearest 
allies,  and  not  liable  to  be  injured  by  their  spurs,  so  that 
the  spurs  have  not  been  removed  ?  Or  are  we  to  suppose 
that  the  females  of  these  several  species  especially  require 
spurs  for  their  defense  ?  It  is  a  more  probable  conclusion 
that  both  the  presence  and  absence  of  spurs  in  the  females 
result  from  different  laws  of  inheritance  having  prevailed, 
independently  of  natural  selection.  With  the  many 
females  in  which  spurs  appear  as  rudiments  we  may  con- 
clude that  some  few  of  the  successive  variations,  through 
which  they  were  developed  in  the  males,  occurred  very 
early  in  life  and  were  consequently  transferred  to  the 
females.  In  the  other  and  much  rarer  cases  in  which  the 
females  possess  fully  developed  spurs  we  may  conclude 
that  all  the  successive  variations  were  transferred  to  them; 
and  that  they  gradually  acquired  and  inherited  the  habit 
of  not  disturbing  their  nests. 

The  vocal  organs  and  the  feathers  variously  modified  for 
producing  sound,  as  well  as  the  proper  instincts  for  using 
them,  often  differ  in  the  two  sexes,  but  are  sometimes  the 
same  in  both.  Can  such  differences  be  accounted  for  by  the 
males  having  acquired  these  organs  and  instincts,  while  the 
females  have  been  saved  from  inheriting  them,  on  account 
of  the  danger  to  which  they  would  have  been  exposed  by 
attracting  the  attention  of  birds  or  beasts  of  prey?  This 
does  not  seem  to  me  probable,  when  we  think  of  the 
multitude   of    birds  which    with    impunity  gladden    the 


BIRDS.  513 

country  with  their  voices  during  the  spring.  *  It  is  a  safer  con- 
clusion that,  as  vocal  and  instrumental  organs  are  of  special 
service  only  to  the  males  during  their  courtship,  these 
organs  were  developed  through  sexual  selection  and  their 
constant  use  in  that  sex  alone — the  successive  variations 
and  the  effects  of  use  having  been  from  the  first  more  or  less 
limited  in  transmission  to  the  male  offspring. 

Many  analogous  cases  could  be  adduced ;  those,  for 
instance,  of  the  plumes  on  the  head  being  generally  longer 
in  the  male  than  in  the  female,  sometimes  of  equal  length 
in  both  sexes,  and  occasionally  absent  in  the  female — these 
several  cases  occurring  in  the  same  group  of  birds.  It 
would  be  difficult  to  account  for  such  a  difference  between 
the  sexes  by  the  female  having  been  benefited  by  possessing 
a  slightly  shorter  crest  than  the  male,  and  its  consequent 
diminution  or  complete  suppression  through  natural  selec- 
tion. But  I  will  take  a  more  favorable  case,  namely,  the 
length  of  the  tail.  The  long  train  of  the  peacock  would 
have  been  not  only  inconvenient  but  dangerous  to  the 
peahen  during  the  period  of  incubation  and  while  accom- 
panying her  young.  Hence,  there  is  not  the  least  a  priori 
improbability  in  the  development  of  her  tail  having  been 
checked  through  natural  selection.  But  the  females  of 
various  pheasants,  which  apparently  are  exposed  on  their 
open  nests  to  as  much  danger  as  the  peahen,  have  tails  of 
considerable  length.  The  females  as  well  as  the  males  of 
the  Menura  superha  have  long  tails,  and  they  build  a 
domed  nest,  which  is  a  great  anomaly  in  so  large  a  bird. 
Naturalists  have  wondered  how  the  female  menura  could 
manage  her  tail  during  incubation;  but  it  is  now  knoT\Ti  f 
that  she  '^  enters  the  nest  head  first,  and  then  turns  round, 
with  her  tail  sometimes  over  her  back,  but  more  often  bent 
round  by  her  side.  Thus  in  time  the  tail  becomes  quite 
askew,  and  is  a  tolerable  guide  to  the  length  of  time  the 
bird  has  been  sitting."  Both  sexes  of  an  Australian  king- 
fisher {Tanysiptera  sylvia)  have  the  middle  tail-feathers 
greatly  lengthened,  and  the  female  makes  her  nest  in  a 

*Daines  Barrington,  however,  thought  it  probable  ("  Phil.  Trans- 
act.," 1773,  p.  164)  that  few  female  birds  sing,  because  the  talent 
would  have  been  dangerous  to  them  during  incubation.  He  adds 
that  a  similar  view  may  possibly  account  for  the  inferiority  of  the 
female  to  the  male  in  plumage. 

f  Mr.  Kamsay,  in  "Proc.  Zoolog.  Soc.,"  1868,  p.  50, 


514  THE  DESCENT  OF  MAN. 

hole;  and,  as  I  am  informed  by  Mr.  R.  B.  Sharpe,  these 
feathers  become  much  crumpled  during  incubation. 

In  these  two  latter  cases  the  great  length  of  the  tail- 
feathers  must  be  in  some  degree  inconvenient  to  the  female; 
and  as  in  both  species  tlie  tail-feathers  of  the  female  are 
somewhat  shorter  than  those  of  the  male,  it  might  be 
argued  that  their  full  development  had  been  prevented 
through  natural  selection.  But  if  the  development  of  the 
tail  of  the  peahen  had  been  checked  only  when  it  became 
inconveniently  or  dangerously  great  she  would  have  retained 
a  much  longer  tail  than  she  actually  possesses;  for  her  tail 
is  not  nearly  so  long,  relatively  to  the  size  of  her  body,  as 
that  of  many  female  pheasants,  nor  longer  than  that  of 
the  female  turkey.  It  must  also  be  borne  in  mind  that,  in 
accordance  with  this  view,  as  soon  as  the  tail  of  the  peahen 
became  dangerously  long,  and  its  development  was  conse- 
quently checked,  she  would  have  continually  reacted  on  her 
male  progeny,  and  thus  have  prevented  the  peacock  from 
acquiring  his  present  magnificent  train.  We  may,  there- 
fore, infer  that  the  length  of  the  tail  in  the  peacock  and 
its  shortness  in  the  peahen  are  the  result  of  the  requisite 
variations  in  the  male  having  been  from  the  first  trans- 
mitted to  the  male  offspring  alone. 

We  are  led  to  a  nearly  similar  conclusion  with  respect  to 
the  length  of  the  tail  in  the  various  species  of  pheasants. 
In  the  eared  pheasant  ( Crossoptilo7i  auritum)  the  tail  is  of 
equal  length  in  both  sexes,  namely,  sixteen  or  seventeen 
inches;  in  the  common  pheasant  it  is  about  twenty  inches 
long  in  the  male  and  twelve  in  the  female;  in  Scemmerring's 
pheasant,  thirty-seven  inches  in  the  male  and  only  eight  in 
the  female;  and  lastly,  in  Eeeve's  pheasant  it  is  sometimes 
actually  seventy-two  inches  long  in  the  male  and  sixteen 
in  tlie  female.  Thus  in  the  several  species  the  tail  of  the 
female  differs  much  in  length  irrespectively  of  that  of  the 
male;  and  this  can  be  accounted  for,  as  it  seems  to  me, 
with  much  more  probability,  by  the  laws  of  inheritance — 
that  is,  by  the  successive  variations  having  been  from  the 
first  more  or  less  closely  limited  in  their  transmission  to 
the  male  sex  than  by  the  agency  of  natural  selection, 
resulting  from  the  length  of  tail  being  more  or  less  injuri- 
Qus  to  the  females  of  these  several  allied  species. 

We  niay  now  consider  Mr.  Wallace's  arguments  in  regard 


BIRDS.  515 

to  the  sexual  coloration  of  birds.  He  believes  that  the 
bright  tints  originally  acquired  through  sexual  selection  by 
the  males  would  in  all,  or  almost  all  cases,  have  been  trans- 
mitted to  the  females,  unless  the  transference  had  been 
checked  through  natural  selection.  I  may  here  remind 
the  reader  that  various  facts  opposed  to  this  view  have 
already  been  given  under  reptiles,  amphibians,  fishes  and 
lepidoptera.  Mr.  Wallace  rests  his  belief  chiefly,  but  not 
exclusively,  as  we  shall  see  in  the  next  chapter,  on  the  fol- 
lowing statement,*  that  when  both  sexes  are  colored  in  a 
very  conspicuous  manner  the  nest  is  of  such  a  nature  as  to 
conceal  the  sitting  bird;  but  when  there  is  a  marked  con- 
trast of  color  between  the  sexes,  the  male  being  gay  and 
the  female  dull  colored,  the  nest  is  open  and  exposes  the 
sitting  bird  to  view.  This  coincidence,  as  far  as  it  goes, 
certainly  seems  to  favor  the  belief  that  the  females  which 
sit  on  open  nests  have  been  specially  modified  for  the  sake 
of  protection;  but  we  shall  presently  see  that  there  is  an- 
other and  more  probable  explanation,  namely,  that  con- 
spicuous females  have  acquired  the  instinct  of  building 
domed  nests  oftener  than  dull-colored  birds.  Mr.  Wallace 
admits  that  there  are,  as  might  have  been  expected,  some 
exceptions  to  his  two  rules,  but  it  is  a  question  whether 
the  exceptions  are  not  so  numerous  as  seriously  to  invalidate 
them. 

There  is,  in  the  first  place,  much  truth  in  the  Duke  of 
ArgylFs  remark f  that  a  large  domed  nest  is  more  con- 
spicuous to  an  enemy,  especially  to  all  tree-hauntiug  carniv- 
orous animals,  than  a  smaller  open  nest.  Nor  must  we 
forget  that  with  many  birds  which  build  open  nests  the 
male  sits  on  the  eggs  and  aids  the  female  in  feeding  the 
young;  this  is  the  case,  for  instance,  with  Pyranga  cestiva,l 
one  of  the  most  splendid  birds  in  the  United  States,  the 
male  being  vermilion  and  the  female  light  brownish-green. 
Now  if  brilliant  colors  had  been  extremely  dangerous  to 
birds  while  sitting  on  their  open  nests  the  males  in  these 
cases  would  have  suffered  greatly.  It  might,  however,  be 
of  such  paramount  importance  to  the  male  to  be  brilliantly 
colored  in  order  to  beat  his  rivals  that  this  may  have  more 
than  compensated  some  additional  danger. 

♦"Journal  of  Travel,"  edited  by  A.  Murray,  vol.  i,  1868,  p.  78. 
t  "Journal  of  Travel,"  edited  by  A.  Murray,  vol.  i,  1868,  p.  ^1, 
I  AiiduboQ,  '■  Ornithological  Biography,"  vol.  i,  p.  333. 


516  THE  DESCENT  OF  MAN. 

Mr.  Wallace  admits  that  with  the  king-crows  (Dicruriis). 
orioles,  and  Pittidae,  the  females  are  conspicuously  colored, 
yet  build  open  nests;  but  he  urges  that  the  birds  of  the  first 
group  are  highly  pugnacious  and  could  defend  themselves; 
that  those  of  the  second  group  take  extreme  care  in  con- 
cealing their  open  nests,  but  this  does  not  invariably  hold 
good;*  and  that  with  the  birds  of  the  third  group  the 
females  are  brightly  colored,  chiefly  on  the  under  surface. 
Besides  these  cases,  pigeons,  which  are  sometimes  brightly 
and  almost  always  conspicuously  colored,  and  which  are 
notoriously  liable  to  the  attacks  of  birds  of  prey,  offer  a 
serious  exception  to  the  rule,  for  they  almost  always  build 
open  and  exposed  nests.  In  another  large  family,  that  of 
the  humming-birds,  all  the  species  build  open  nests,  yet 
with  some  of  the  most  gorgeous  species  the  sexes  are  alike; 
and  in  the  majority,  the  females,  though  less  brilliant  than 
the  males,  are  brightly  colored.  Nor  can  it  be  maintained 
that  all  female  humming  -  birds,  which  are  brightly 
colored,  escape  detection  by  their  tints  being  green,  for 
some  display  on  their  upper  surfaces  red,  blue  and  other 
colors,  t 

In  regard  to  birds  which  build  in  holes  or  construct 
domed  nests,  other  advantages,  as  Mr.  Wallace  remarks, 
besides  concealment,  are  gained,  such  as  shelter  from  the 
rain,  greater  warmth,  and  in  hot  countries  protection  from 
the  sun;|  so  that  it  is  no  valid  objection  to  his  view  that 
many  birds  having  both  sexes  obscurely  colored  build  con- 
cealed nests.  §   The  female  horn-bill  (Bticeros),  for  instance, 

*  Jerdon,  "  Birds  of  India,  '  vol.  ii,  p.  108.  Gould's  "  Hand-book 
to  tlie  Birds  of  Australia,"  vol.  1,  p.  463. 

f  For  instance,  the  female  Eupetomena  macrotira  has  the  head  and 
tail  dark  blue  with  reddish  loins;  the  female  Lampornis  porphyru- 
rus  is  blackish  green  on  the  upper  surface,  with  the  lores  and  sides 
of  the  throat  crimson;  the  female  Eulampis  jugularis  has  the  top  of 
the  head  and  back  green,  but  the  loins  and  the  tail  are  crimson. 
Many  other  instances  of  highly  conspicuous  females  could  be  given. 
See  Mr.  Gould's  magnificent  work  on  this  family. 

X  Mr.  Salvin  noticed  in  Guatemala  ("  Ibis,"  1864,  p.  375)  that  hum- 
ming-birds were  much  more  unwilling  to  leave  their  nests  during 
very  hot  weather,  when  the  sun  was  shining  brightly,  as  if  their 
e^gfi  would  be  thus  injured,  than  during  cool,  cloudy  or  rainy 
weather. 

§1  may  specify,  as  instances  of  dull  colored  birds  building  con- 
cealed nests,  the  species  belonging  to  eight  Australian  genera 
described  in  Gould's  "  Hand-book  to  the  Birds  of  Australia,"  vol.  i, 
pp.  340,  362,  365,  383,  387,  389,  391,  414. 


BIRDS.  517 

of  India  and  Africa,  is  protected  during  incubation  with 
extraordinary  care,  for  she  plasters  up  with  her  own  excre- 
ment the  orifice  of  tlie  hole  in  which  she  sits  on  her  eggs, 
leaving  only  a  small  orifice  through  which  the  male  feeds 
her;  she  is  thus  kept  a  close  prisoner  during  the  whole 
period  of  incubation;*  yet  female  horn-bills  are  not  more 
conspicuously  colored  than  many  other  birds  of  equal  size 
which  build  open  nests.  It  is  a  more  serious  objection  to 
Mr.  Wallace's  view,  as  is  admitted  by  him,  that  in  some  few 
gi'oups  the  males  are  brilliantly  colored  and  the  females 
obscure,  and  yet  the  latter  hatch  their  eggs  in  domed  nests. 
This  is  the  case  with  the  Grallinae  of  Australia,  the  superb 
warblers  (Maluridae)  of  the  same  country,  the  sun-birds 
(Xectarinise),  and  with  several  of  the  Australian  honey- 
suckers  or  Meliphagidae.  f 

If  we  look  to  tile  birds  of  England  we  shall  see  that 
there  is  no  close  and  general  relation  between  the  colors  of 
tiie  female  and  the  nature  of  the  nest  which  is  constructed. 
About  forty  of  our  British  birds  (excluding  those  of 
large  size  which  could  defend  themselves)  build  in  holes  in 
banks,  rocks  or  trees  or  construct  domed  nests.  If  we  take 
the  colors  of  the  female  goldfinch,  bullfinch  or  blackbird 
as  a  standard  of  the  degree  of  conspicuousness,  which  is 
not  highly  dangerous  to  the  sitting  female,  then  out  of  the 
above  forty  birds  the  females  of  only  twelve  can  be  consid- 
ered as  conspicuous  to  a  dangerous  degree,  the  remaining 
twenty  -  eight  being  inconspicuous.  J      Nor  is  there  any 

♦Mr.  C.  Home,  "Proc.  Zoolog.  Soc.,"  1869,  p.  243. 

f  On  the  nidification  and  colors  of  these  latter  species,  see  Gould's 
"  Hand-book,"  etc.,  vol.  i,  pp.  504,  527. 

X  I  have  consulted,  on  this  subject,  Macgillivray's  "  British  Birds," 
and  though  doubts  may  be  entertained  in  some  cases  in  regard  to  the 
degree  of  concealment  of  the  nest  and  to  the  degree  of  conspicuous- 
ness of  the  female,  yet  the  following  birds,  which  all  lay  their  eggs 
in  holes  or  in  domed  nests,  can  hardly  be  considered,  by  the  above 
standard,  as  conspicuous:  Passer,  2  species;  Sturnus,  of  which  the 
female  is  considerably  less  brilliant  than  the  male;  Cinclus;  Motal- 
lica  boarula  (?);  Erithacus  (?):  Fruticola,  2  sp. :  Saxicola;  Ruticilla,  2 
sp.;  Sylvia,  3  sp.;  Parus,  3  sp. ;  Mecistura;  Anorthura;  Certhia; 
Sitta;  Yunx;  Muscicapa,  2sp. ;  Hirundo,  3  sp. ;  and  Cypselus.  The 
females  of  the  following  12  birds  may  be  considered  as  conspicuous 
according  to  the  same  standard,  viz..  Pastor,  Motacilla  alba,  Parus 
major  and  P.  caeruleus,  Upupa,  Picus,  4  sp.,  Coracias,  Alcedo  and 
Merops. 


518  THE  DESCENT  OE  MAN. 

close  relation  within  the  same  genus  between  a  well -pro- 
nounced difference  in  color  between  the  sexes  and  the 
nature  of  the  nest  constructed.  Thus  the  male  house- 
sparrow  {Passer  domesticus)  differs  much  from  the  female, 
the  male  tree-sparrow  {P.  montanus)  hardly  at  all,  and  yet 
both  build  well-concealed  nests.  The  two  sexes  of  the 
common  fly-catcher  {Muscicapa  gr-isola)  can  hardly  be 
distinguished,  while  the  sexes  of  the  pied  fly  -  catcher 
(M.  litctuosa)  differ  considerably,  and  both  species  build 
in  holes  or  conceal  their  nests.  The  female  blackbird 
{Turdus  merula)  differs  much,  the  female  ring-ouzel  {T. 
torquatus)  dift'ers  less,  and  the  female  common  thrush 
{T.  musicus)  hardly  at  all  from  their  respective  males;  yet 
all  build  open  nests.  On  the  other  hand,  the  not  very 
distantly  allied  water-ouzel  (Ciriclus  aquaticus)  builds  a 
domed  nest,  and  the  sexes  differ  about  as  much  as  in  the 
ring-ouzel.  The  black  and  red  gvou^Q  (Tetrao  tetrix  2iiidi 
T.  scoticus)  build  open  nests  in  equally  well-concealed 
spots,  but  in  the  one  species  the  sexes  differ  greatly,  and 
in  the  other  very  little. 

Notwithstanding  the  foregoing  objections,  I  cannot 
doubt,  after  reading  Mr.  Wallace's  excellent  essay,  that 
looking  to  the  birds  of  the  world  a  large  majority  of  the 
species  in  which  the  females  are  conspicuously  colored  (and 
in  this  case  the  males  with  rare  exceptions  are  equally 
conspicuous)  build  concealed  nests  for  the  sake  of  protec- 
tion. Mr.  Wallace  enumerates*  a  long  series  of  groups  in 
which  this  rule  holds  good;  but  it  will  suffice  here  to  give 
as  instances  the  more  familiar  groups  of  kingfishers,  tou- 
cans, trogons,  puff'-birds  (Capitonidse),  plantain  -  eaters 
(Musophagae),  woodpeckers  and  parrots.  Mr.  Wallace 
believes  that  in  these  groups,  as  the  males  gradually  ac- 
quired through  sexual  selection  their  brilliant  colors,  these 
were  transferred  to  the  females  and  were  not  eliminated  by 
natural  selection  owing  to  the  protection  which  the  already 
enjoyed  from  their  manner  of  nidification.  According  to 
this  view,  their  present  manner  of  nestling  was  acquired 
before  their  present  colors.  But  it  seems  to  me  much 
more  probable  that  in  most  cases,  as  the  females  were 
gradually  rendered  more  and  more  brilliant  from  partaking 
of  the  colors  of  the  male,  they  were  gradually  led  to  change 

*  "Journal  of  Travel,"  edited  by  A.  Murray,  vol.  i,  p.  78. 


BIRDS.  519 

their  instincts  (supposing  that  they  originally  built  open 
nests)  and  to  seek  protection  by  building  domed  or  con- 
cealed nests.  No  one  who  studies,  for  instance,  Audubon's 
account  of  the  differences  in  the  nests  of  the  same  species 
in  the  Northern  and  Southern  United  States,*  will  feel 
any  great  difficulty  in  admitting  that  birds,  either  by  a 
change  (in  the  strict  sense  of  the  word)  of  their  habits,  or 
through  the  natural  selection  of  so-called  spontaneous 
variations  of  instinct,  might  readily  be  led  to  modify  their 
manner  of  nesting. 

This  way  of  viewing  the  relation,  as  far  as  it  holds  good, 
between  the  bright  colors  of  female  birds  and  their  manner 
of  nesting  receives  some  support  from  certain  cases  occur- 
ring in  the  Sahara  Desert.  Here,  as  in  most  other  deserts, 
various  birds  and  many  other  animals  have  had  their  colors 
adapted  in  a  wonderful  manner  to  the  tints  of  the  surround- 
ing surfaee.  Nevertheless  there  are,  as  I  am  informed  by 
the  Rev.  Mr.  Tristram,  some  curious  exceptions  to  the  rule; 
thus  the  male  of  the  Monticola  cyanea  is  conspicuous  from 
his  bright-blue  color,  and  the  female  almost  equally  con- 
spicuous from  her  mottled  brown  and  white  plumage;  both 
sexes  of  two  species  of  Dromolaea  are  of  a  lustrous  black;  so 
that  these  three  species  are  far  from  receiving  protection 
from  their  colors,  yet  they  are  able  to  survive,  for  they  have 
acquired  the  habit  of  taking  refuge  from  danger  in  holes 
or  crevices  in  the  rocks. 

With  respect  to  the  above  groups  in  which  the  females 
are  conspicuously  colored  and  build  concealed  nests,  it  is 
not  necessary  to  suppose  that  each  separate  species  had  its 
nidifying  instinct  specially  modified;  but  only  that  the 
early  progenitors  of  each  group  were  gradually  led  to  build 
domed  or  concealed  nests,  and  afterward  transmitted  this 
instinct,  together  with  their  bright  colors,  to  their  modified 
descendants.  As  far  as  it  can  be  trusted  the  conclusion  is 
interesting,  that  sexual  selection,  together  with  equal  or 
nearly  equal  inheritance  by  both  sexes,  have  indirectly 
determined  the  manner  of  nidification  of  whole  groups  of 
birds. 

According  to  Mr.  Wallace,  even  in  the  groups  in  which 

♦See  many  statements  in  the   "Ornithological  Biography."     See 
also  some  curious  observations  on   the   nests  of   Italian   birds  by 
Eugenio  Bettoni,  in  the  "  Aiti  della  Societa  Italiana,"  vol.  x 
p.  487. 


520  THE  DESCENT  OF  MAK, 

the  females,  from  being  protected  in  domed  nests  during 
incubation,  have  not  had  their  bright  colors  eliminated 
through  natural  selection,  the  males  often  differ  in  a  slight 
and  occasionally  in  a  considerable  degree  from  the  females. 
This  is  a  significant  fact,  for  such  differences  in  color  must  be 
accounted  for  by  some  of  the  variations  in  the  males  having 
been  from  the  first  limited  in  transmission  to  the  same  sex; 
as  it  can  hardly  be  maintained  that  these  differences,  espe- 
cially when  very  slight,  serve  as  a  protection  to  the  female. 
Thus  all  the  species  in  the  splendid  group  of  the  Trogons 
build  in  holes;  and  Mr.  Gould  gives  figures*  of  both  sexes 
of  twenty-five  species,  in  all  of  which,  with  one  partial 
exception,  the  sexes  differ  sometimes  slightly,  sometimes 
conspicuously  in  color — the  males  being  always  finer  than 
the  females,  though  the  latter  are  likewise  beautiful.  All 
the  species  of  king-fishers  build  in  holes,  and  with  most  of  the 
species  the  sexes  are  equally  brilliant,  and  thus  far  Mr.  Wal- 
lace's rule  holds  good;  but  in  some  of  the  Australian  species 
the  colors  of  the  females  are  rather  less  vivid  than  those 
of  the  male ;  and  in  one  splendidly  colored  species  the 
sexes  differ  so  much  that  they  were  at  first  thought  to  be 
specifically  distinct,  f  Mr.  R.  B.  Sharpe,  who  has  espe- 
cially studied  this  group,  has  shown  me  some  American 
species  (Ceryle)  in  which  the  breast  of  the  male  is  belted 
with  black.  Again,  in  Carcineutus,  the  difference  between 
the  sexes  is  conspicuous;  in  the  male  the  upper  surface  is 
dull-blue  banded  with  black,  the  lower  surface  being  partly 
fawn-colored,  and  there  is  much  red  about  the  head ;  in  the 
female  the  upper  surface  is  reddish-brown  banded  with 
black,  and  the  lower  surface  white  with  black  markings. 
It  is  an  interesting  fact,  as  showing  how  the  same  peculiar 
style  of  sexual  coloring  often  characterizes  allied  forms, 
that  in  three  species  of  Dacelo  the  male  differs  from  the 
female  only  in  the  tail  being  dull-hlue  banded  with  black, 
while  that  of  the  female  is  brown  with  blackish  bars;  so 
that  here  the  tail  differs  in  color  in  the  two  sexes  in  exactly 
tlie  same  manner  as  the  whole  upper  surface  in  the  two 
sexes  of  Carcineutes. 

With  parrots,  which  likewise  build  in  holes,  we  find 

*  See  his  "Monograph  of  the  Trogonidae,"  first  edition. 
+  Namely  Cyanalcyon.     Gould's  "  Hand-book  to  the  Birds  of  Aus- 
tralia," vol.  i,  p.  133;  see  also  pp.  130,  136. 


BIRDS,  521 

analogous  cases;  in  most  of  the  species  both  sexes  are 
brilliantly  colored  and  indistinguishable,  but  in  not  a  few 
species  the  males  are  colored  rather  more  vividly  than  the 
females,  or  even  very  differently  from  them.  Thus,  besides 
other  strongly  marked  differences,  the  whole  under  surface 
of  the  male  king  lory  {Aprosmictus  scapulatus)  is  scarlet, 
while  the  throat  and  chest  of  the  female  is  green  tinged 
with  red;  in  the  Euphema  splendida  there  is  a  similar  dif- 
ference, the  face  and  wing  coverts  moreover  of  the  female 
being  of  a  paler  blue  than  in  the  male.  *  In  the  family  of  the 
tits  {Parince),  which  build  concealed  nests,  the  female 
of  our  common  blue  tomtit  {Par us  ccer ulcus)  is  "  much 
less  brightly  colored "  than  the  male ;  and  in  the 
magnificent  Sultan  yellow  tit  of  India  the  difference  is 
greater,  f 

Again,  in  the  great  group  of  the  woodpeckers,  J;  the  sexes 
are  generally  nearly  alike,  but  in  the  Megapicus  validus  all 
those  parts  of  the  head,  neck  and  breast  which  are  crimson 
in  the  male  are  pale-brown  in  the  female.  As  in  several 
woodpeckers  the  head  of  the  male  is  bright  crimson,  while 
that  of  the  female  is  plain,  it  occurred  to  me  that  this  color 
might  possibly  make  the  female  dangerously  conspicuous 
whenever  she  put  her  head  out  of  the  hole  containing  her 
nest,  and  consequently  that  this  color,  in  accordance  with 
Mr.  Wallace^s  belief,  had  been  eliminated.  This  view  is 
strengthened  by  what  Malherbe  states  with  respect  to 
Indopicus  carlotta;  namely,  that  the  young  females,  like  the 
young  males,  have  some  crimson  about  their  heads,  but  that 
this  color  disappears  in  the  adult  female,  while  it  is  intensi- 
fied in  the  adult  male.  Nevertheless,  the  following  con- 
siderations render  this  view  extremely  doubtful  ;  the  male 
takes  a  fair  share  in  incubation, §  and  would  be  thus  almost 
equally  exposed  to  danger;  both  sexes  of  many  species  have 
their  heads  of  an  equally  bright  crimson;  in  other  species 

*  Every  gradation  of  difference  between  the  sexes  may  be  followed 
in  the  parrots  of  Australia.  See  Gould's  "  Hand-book,"  etc.,  vol.  ii, 
pp.  14-102. 

f  Macgillivray's  "  British  Birds,"  vol.  ii,  p.  433.  Jerdon,  "  Birds 
of  India,"  vol.  ii,  p.  282. 

X  All  the  following  facts  are  taken  from  M.  Malherbe's  magnificent 
"  Monographic  des  Picidees,"  1861. 

§  Audubon's  "Ornithological  Biography,"  vol.  ii,  p.  75;  see  also 
the  "  Ibis,"  vol.  i,  p.  268. 


522  THE  DESCENT  OF  MAN. 

the  difference  between  the  sexes  in  the  amount  of  scarlet  is 
so  slight  that  it  can  hardly  make  any  appreciable  difference 
in  the  danger  incurred;  and  lastly,  the  coloring  of  the 
head  in  the  two  sexes  often  differs  slightly  in  other  ways. 

The  cases,  as  yet  given,  of  slight  and  graduated  differ- 
ences in  color  between  the  males  and  females  in  the  groups, 
in  which,  as  a  general  rule,  the  sexes  resemble  each  other, 
all  relate  to  species  which  build  domed  or  concealed  nests. 
But  similar  gradations  may  likewise  be  observed  in  groups 
in  which  the  sexes  as  a  general  rule  resemble  each  other, 
but  wliich  build  open  nests. 

As  I  have  before  instanced  the  Australian  parrots,  so  I 
may  here  instance,  without  giving  any  details,  the  Austra- 
lian pigeons.  *  It  deserves  especial  notice  that  in  all  these 
cases  the  slight  differences  in  plumage  between  the  sexes 
are  of  the  same  general  nature  as  the  occasionally  greater 
differences.  A  good  illustration  of  this  fact  has  already 
been  afforded  by  those  kingfishers  in  which  either  the  tail 
alone  or  the  whole  upper  surface  of  the  plumage  differs  in 
the  same  manner  in  the  two  sexes.  Similar  cases  may  be 
observed  with  parrots  and  pigeons.  The  differences  in  color 
between  the  sexes  of  the  same  species  are,  also,  of  the  same 
general  nature  as  the  differences  in  color  between  the  dis- 
tinct species  of  the  same  group.  For  when  in  a  group  in 
which  the  sexes  are  usually  alike  the  male  differs  considera- 
bly from  the  female  he  is  not  colored  in  a  quite  new  style. 
Hence  we  may  infer  that  within  the  same  group  the  special 
colors  of  both  sexes  when  they  are  alike,  and  the  colors  of 
the  male  when  he  differs  slightly  or  even  considerably  from 
the  female,  have  been  in  most  cases  determined  by  the  same 
general  cause;  this  being  sexual  selection. 

It  is  not  probable,  as  has  already  been  remarked,  that 
differences  in  color  between  the  sexes,  when  very  slight, 
can  be  of  service  to  the  female  as  a  protection.  Assuming, 
however,  that  they  are  of  service,  they  might  be  thought  to 
be  cases  of  transition;  but  we  have  no  reason  to  believe  that 
many  species  at  any  one  time  are  undergoing  change. 
Therefore  we  can  hardly  admit  that  the  numerous  females 
which  differ  very  slightly  in  color  from  their  males  are  now 
all  commencing  to  become  obscure  for  the  sake  of  protection. 

*  Gould's  "  Hand-book  to  the  Birds  of  Australia,"  vol.  ii,  pp. 
109-149. 


BIRDS,  523 

Even  if  we  consider  somewhat  mofe  marked  sexual  differ- 
[?nces,  is  it  probable,  for  instance,  that  the  head  of  the 
female  chaffinch,  the  crimson  on  the  breast  of  the  female 
bullfinch,  the  green  of  the  female  greenfinch,  the  crest  of 
the  female  golden-crested  wren  have  all  been  rendered  less 
bright  by  the  slow  process  of  selection  for  the  sake  of  pro- 
tection ?  I  cannot  think  so;  and  still  less  with  the  slight 
differences  between  the  sexes  of  those  birds  which  build 
concealed  nests.  On  the  other  hand,  the  differences  in 
color  between  the  sexes,  whether  great  or  small,  may  to  a 
large  extent  be  explained  on  the  principle  of  the  successive 
variations  acquired  by  the  males  through  sexual  selection, 
having  been  from  the  first  more  or  less  limited  in  their 
transmission  to  the  females.  That  the  degree  of  limitation 
should  differ  in  different  species  of  the  same  group  will  not 
surprise  any  one  who  has  studied  the  laws  of  inheritance, 
for  they  are  so  complex  that  they  appear  to  us  in  our  igno- 
rance to  be  capricious  in  their  actions.* 

As  far  as  I  can  discover  there  are  few  large  groups  of 
birds  in  which  all  the  species  have  both  sexes  alike  and 
brilliantly  colored,  but  I  hear  from  Mr.  Sclater  that  this 
appears  to  be  the  case  with  the  Musophagae  or  plantain- 
eaters.  Nor  do  I  believe  that  any  large  group  exists  in 
which  the  sexes  of  all  the  species  are  widely  dissimilar  in 
color.  Mr.  Wallace  informs  me  that  the  chatterers  of 
South  America  (Cotingidce)  offer  one  of  the  best  instances; 
but  with  some  of  the  species  in  which  the  male  has  a  splen- 
did red  breast  the  female  exhibits  some  red  on  her  breast; 
and  the  females  of  other  species  show  traces  of  the  green 
and  other  colors  of  the  males.  Nevertheless  we  have  a 
near  approach  to  close  sexual  similarity  or  dissimilarity 
throughout  several  groups;  and  this,  from  what  has  iilst 
been  said  of  the  fluctuating  nature  of  inheritance,  is  a 
somewhat  surprising  circumstance.  But  that  the  same 
laws  should  largely  prevail  with  allied  animals  is  not  sur- 
prising. The  domestic  fowl  has  produced  a  great  number 
of  breeds  and  sub-breeds,  and  in  these  the  sexes  generally 
differ  in  plumage;  so  that  it  has  been  noticed  as  an  un- 
usual circumstance  when  in  certain  sub -breeds  they 
resemble   each   other.     On  the  other  hand,  the  domestic 

*See  remarks  to  this  effect  in  my  work  on  "Variation  under 
Domestication,"  vol.  ii,  chap.  xii. 


524  THE  DESCENT  OF  MAN. 

pigeon  has  likewise  produced  a  vast  number  of  distinci 
breeds  and  sub-breeds,  and  in  these,  with  rare  exceptions, 
the  two  sexes  are  identically  alike. 

Therefore  if  other  species  of  G alius  and  Columba  wen 
domesticated  and  varied  it  would  not  be  rash  to  predici 
that  similar  rules  of  sexual  similarily  and  dissimilaritj 
depending  on  the  form  of  transmission  would  hold  good  ii 
both  cases.  In  like  manner  the  same  form  of  transmissioi 
has  generally  prevailed  under  nature  throughout  the  sanii 
groups,  although  marked  exceptions  to  this  rule  occur 
Thus  within  the  same  family,  or  even  genus,  the  sexes  mai 
be  identically  alike  or  very  different  in  color.  Instancei 
have  already  been  given  in  the  same  genus,  as  with  spar 
rows,  fly-catchers,  thrushes  and  grouse.  In  the  family  o: 
pheasants  the  sexes  of  almost  all  the  species  are  wonder 
fully  dissimilar,  but  are  quite  alike  in  the  eared  pheasan 
or  Crossoptilon  auritum.  In  two  species  of  Chloephaga 
a  genus  of  geese,  the  male  cannot  be  distinguished  fron 
the  females  except  by  size;  while  in  two  others  the  sexei 
are  so  unlike  that  they  might  easily  be  mistaken  for  distinc 
species.  * 

The  laws  of  inheritance  can  alone  account  for  the  fol 
lowing  cases  in  which  the  female  acquires  late  in  lifi 
certain  characters  proper  to  the  male,  and  ultimately 
comes  to  resemble  him  more  or  less  completely.  Here  pro 
tection  can  hardly  have  come  into  play.  Mr.  Blytli  in 
forms  me  that  the  females  of  Oriolus  mela7iocepUalus  an( 
of  some  allied  species  when  sufficiently  mature  to  bree( 
differ  considerably  in  plumage  from  the  adult  males;  bu 
after  the  second  or  third  moults  they  differ  only  in  thei 
beaks  having  a  slight  greenish  tinge.  In  the  dwarf  bittern 
(Ardetta),  according  to  the  same  authority,  ^'  the  mal< 
acquires  his  final  livery  at  the  first  moult;  the  female  no 
before  the  third  or  fourth  moult;  in  the  meanwhile  she  pre 
sents  an  intermediate  garb,  which  is  ultimately  exchangee 
for  the  same  livery  as  that  of  the  male."  So,  again,  th( 
female  Falco  peregrmus  acquires  her  blue  plumage  mon 
slowly  than  the  male.  Mr.  Swinhoe  states  that  with  one  o 
the  drongo  shrikes  (Dicrurus  macrocercus)  the  male,  whil< 
almost  a  nestling,  molts  his  soft  brown  plumage  anc 
becomes  of  a  uniform  glossy  greenish-black;  but  the  femaL 

*Tlie  "Ibis,"  vol.  vi,  1864,  p.  122. 


BIRDS.  525 

stains  for  a  long  time  the  white  striae  and  spots  on  the 
ixiliarv  feathers;  and  does  not  completely  assume  the  uni- 
form black  color  of  the  male  for  three  years.  The  same 
excellent  observer  remarks  that  in  the  spring  of  the 
second  year  the  female  spoon-bill  (Platalea)  of  China 
resembles  the  male  of  the  first  year,  and  that  apparently  it 
is  not  until  the  third  spring  that  she  acquires  the  same 
adult  plumage  as  that  possessed  by  the  male  at  a  much 
earlier  age.  The  female  Bomhy cilia  carolinensis  differs 
very  little  from  the  male,  but  the  appendages,  which  like 
beads  of  red  sealing-wax  ornament  the  wing-feathers,*  are 
not  developed  in  her  so  early  in  life  as  in  the  male.  In  the 
male  of  an  Indian  paroquet  (Palwornis  javanicus)  the 
upper  mandible  is  coral-red  from  his  earliest  youth,  but  in 
the  female,  as  Mr.  Blyth  has  observed  with  caged  and  wild 
birds,  it  is  at  first  black  and  does  not  become  red  until  the 
bird  is  at  least  a  year  old,  at  which  age  the  sexes  resemble 
each  other  in  all  respects.  Both  sexes  of  the  wild  turkey 
are  ultimately  furnished  with  a  tuft  of  bristles  on  the 
breast,  but  in  two-year-old  birds  the  tuft  is  about  four 
inches  long  in  the  male  and  hardly  apparent  in  the  female; 
when,  however,  the  latter  has  reached  her  fourth  year,  it  is 
from  four  to  five  inches  in  length,  f 

These  cases  must  not  be  confounded  with  those  where 
diseased  or  old  females  abnormally  assume  masculine  char- 
acters, nor  with  those  where  fertile  females,  while  young, 
acquire  the  characters  of  the  male,  through  variation  or 
some  unknown  cause.  I     But  all  these  cases  have  so  much 

*  When  the  male  courts  the  female,  these  ornaments  are  vibrated, 
and  "  are  shown  off  to  great  advantage,"  on  the  outstretched  wings: 
A.  Leith  Adams,  "Field  and  Forest  Rambles,"  1873,  p.  153. 

f  On  Ardetta,  Translation  of  Cuvier's  "Regne  Animal,"  by  Mr. 
Blvth,  foot  note  p.  159.  On  the  Peregrine  Falcon,  Mr.  Blvth,  in 
Charles  worth's  "Mag.  of  Nat.  Hist.,"  vol.  i,  1837,  p.  304.  On 
Dicrurus,  "  Ibis,"  1863,  p.  44.  On  the  Platalea,  "  Ibis,"  vol.  vi,  1864, 
p  366  On  the  Bombycilla,  Audubon's  "  Ornitholog.  Biography," 
vol.  i,  p  229.  On  the  Palaeornis,  see,  also,  Jerdon,  "Birds  of  India," 
vol.  i,  p  263  On  the  wild  turkey,  Audubon,  ibid,  vol.  i,  p.  15;  but 
I  hear  from  Judge  Caton  that  in  Illinois  the  female  very  rarely 
acquires  a  tuft.  Analogous  cases  with  the  females  of  Petrocossyphus 
are  given  by  Mr.  R.  Sharpe,  "  Proc.  Zoolog.  Soc,"  1872,  p.  496. 

I  Of  these  latter  cases  Mr.  Blyth  has  recorded  (Translation  of 
Cuvier's  "  Regne  Animal,"  p.  158)  various  instances  with  Lanius, 
Ruticilla,  Linaria  and  Anas.  Audubon  has  also  recorded  a  similar 
case  ("  Ornith.  Biog.,"  vol.  v,  p.  519)  with  Pyranga  cestiva. 


526  THE  DESCENT  OF  MAN, 

in  common  that  they  depend,  according  to  the  hypothesis 
of  pangenesis,  on  gemmules  derived  from  each  part  of  the 
male  being  present,  though  hitent,  in  the  female;  their 
development  following  on  some  slight  change  in  the  elective 
affinities  of  her  constituent  tissues. 

A  few  words  must  be  added  on  changes  of  plumage  in 
relation  to  the  season  of  the  year.  From  reasons  formerly 
assigned  there  can  be  little  doubt  that  the  elegant  plumes, 
long  pendant  feathers,  crests,  etc.,  of  egrets,  herons  and 
many  other  birds,  which  are  developed  and  retained  only 
during  the  summer,  serve  for  ornamental  and  nuptial  pur- 
poses, though  common  to  both  sexes.  The  female  is  thus  ren- 
dered more  conspicuous  during  the  period  of  incubation  than 
during  the  winter ;  but  such  birds  as  herons  and  egrets 
would  be  able  to  defend  themselves.  As,  however,  plumes 
would  probably  be  inconvenient  and  certainly  of  no  use 
during  the  winter,  it  is  possible  that  the  habit  of  moulting 
twice  in  the  year  may  have  been  gradually  acquired  through 
natural  selection  for  the  sake  of  casting  off  inconvenient 
ornaments  during  the  winter.  But  this  yiew  cannot  be 
extended  to  the  many  waders,  whose  summer  and  winter 
plumages  differ  very  little  in  color.  With  defenseless  spe- 
cies, in  which  both  sexes,  or  the  males  alone,  become 
extremely  conspicuous  during  the  breeding-season — or 
when  the  males  acquire  at  this  season  such  long  wing  or 
tail  feathers  as  to  impede  their  flight,  as  with  Cosmetornis 
and  Vidua — it  certainly  at  first  appears  highly  probable 
that  the  second  moult  has  been  gained  for  the  special  pur- 
pose of  throwing  off  these  ornaments.  We  must,  however, 
remember  that  many  birds,  such  as  some  of  the  birds  of 
paradise,  the  Argus  pheasant  and  peacock,  do  not  cast 
their  plumes  during  the  winter;  and  it  can  hardly  be 
maintained  that  the  constitution  of  these  birds,  at  least  of 
the  Gallinaceae,  renders  a  double  moult  impossible,  for  the 
ptarmigan  moults  thrice  in  the  year.*  Hence  it  must  be 
considered  as  doubtful  whether  the  many  species  which 
moult  their  ornamental  plumes  or  lose  their  bright  colors 
during  the  winter,  have  acquired  this  habit  on  account  of 
the  inconvenience  or  danger  which  they  would  otherwise 
have  suffered. 

*  See  Gould's  "  Birds  of  Great  Britain." 


BIRDS.  527 

I  conclude,  therefore,  that  the  habit  of  moulting  twice 
in  the  year  was  in  most  or  all  cases  first  acquired  for  some 
distinct  purpose,  perhaps  for  gaining  a  warmer  winter  cov- 
ering; and  that  variations  in  the  plumage  occuring  during 
the  summer  were  accumulated  through  sexual  selection, 
and  transmitted  to  the  offspring  at  the  same  season  of  the 
year;  that  such  variations  were  inherited  either  by  both 
sexes  or  by  the  males  alone,  according  to  the  form  of  inher- 
itance which  prevailed.  This  appears  more  probable  than 
that  the  species  in  all  cases  originally  tended  to  retain 
their  ornamental  plumage  during  the  winter,  but  were 
saved  from  this  through  natural  selection,  resulting  from 
the  inconvenience  or  danger  thus  caused. 

I  have  endeavored  in  this  chapter  to  show  that  the  argu- 
ments are  not  trustworthy  in  favor  of  the  view  that  weap- 
ons, bright  colors,  and  various  ornaments  are  now  confined 
to  the  males  owing  to  the  conversion,  by  natural  selection, 
of  the  equal  transmission  of  characters  to  both  sexes,  into 
transmission  to  the  male  sex  alone.  It  is  also  doubtful 
whether  the  colors  of  many  female  birds  are  due  to  the 
preservation,  for  the  sake  of  protection,  of  variations 
which  were  from  the  first  limited  in  their  transmission  to 
the  female  sex.  But  it  will  be  convenient  to  defer  any 
further  discussion  on  this  subject  until  I  treat,  in  the  fol- 
lowing chapter,  of  the  differences  in  plumage  between  the 
young  and  old. 


528  THE  DESCENT  OF  MAN, 


CHAPTER  XVI. 
BiKDS — concluded. 

The  immature  plumage  in  relation  to  the  character  of  the  plumage  in 
both  sexes  when  adult — Six  classes  of  cases — Sexual  differences 
between  the  males  of  closely  allied  or  representative  species — 
The  female  assuming  the  characters  of  the  male — Plumage  of 
the  young  in  relation  to  the  summer  and  winter  plumage  of  the 
adults — On  the  increase  of  beauty  in  the  birds  of  the  world — 
Protective  coloring — Conspicuously  colored  birds — Novelty  appre- 
ciated— Summary  of  the  four  chapters  on  birds. 

We  must  now  consider  the  transmission  of  characters  as 
limited  by  age,  in  reference  to  sexual  selection.  The  truth 
and  importance  of  the  principle  of  inheritance  at  corre- 
sponding ages  need  not  here  be  discussed,  as  enough  has 
already  been  said  on  the  subject.  Before  giving  the  several 
rather  complex  rules  or  classes  of  cases  under  which  the 
differences  in  plumage  between  the  young  and  the  old,  as 
far  as  known  to  me,  may  be  included,  it  will  be  well  to 
make  a  few  preliminary  remarks. 

With  animals  of  all  kinds,  when  the  adults  differ  in  color 
from  the  young,  and  the  colors  of  the  latter  are  not,  as  far 
as  we  can  see,  of  any  special  service,  they  may  generally 
be  attributed,  like  various  embryological  structures,  to  the 
retention  of  a  former  character.  But  this  view  can  be 
maintained  with  confidence  only  when  the  young  of  several 
species  resemble  each  other  closely,  and  likewise  resemble 
other  adult  species  belonging  to  the  same  group;  for  the  latter 
are  the  living  proofs  that  such  a  state  of  things  was  formerly 
possible.  Young  lions  and  pumas  are  marked  with  feeble 
stripes  or  rows  of  spots,  and  as  many  allied  species  both 
young  and  old  are  similarly  marked  no  believer  in  evolution 
will  doubt  that  the  progenitor  of  the  lion  and  puma  was  a 
striped  animal,  and  that  the  young  have  retained  vestiges 
of  the  stripes  like  the  kittens  of  black  cats,  which  are  not 
in  the  least  striped  when  grown  up.     Many  species  of  deer. 


BIRDS.  529 

which  when  mature  are  not  spotted,  are  while  young  cov- 
ered with  white  spots,  as  are  likewise  some  few  species  in  the 
adult  state.  So  again  the  young  in  the  whole  family  of 
pigs  (Suidae),  and  in  certain  rather  distantly  allied  animals, 
such  as  the  tapir,  are  marked  with  dark  longitudinal 
stripes;  but  here  we  have  a  character  apparently  derived 
from  an  extinct  progenitor,  and  now  preserved  by  the  young 
alone.  In  all  such  cases  the  old  have  had  their  colors 
changed  in  the  course  of  time,  while  the  young  have 
remained  but  little  altered,  and  this  has  been  effected 
through  tlie  principle  of  inheritance  at  corresponding  ages. 
This  same  principle  applies  to  many  birds  belonging  to 
various  groups  in  which  the  young  closely  resemble  each 
other,  and  differ  much  from  their  respective  adult  parents. 
The  young  of  almost  all  the  Gallinaceaj  and  of  some  distantly 
allied  birds,  such  as  ostriches,  are  covered  with  longitu- 
dinally striped  down;  but  this  character  points  back  to  a 
state  of  things  so  remote  that  it  hardly  concerns  us.  Young 
cross-bills  (Loxia)  have  at  first  straight  beaks  like  those  of 
other  finches,  and  in  their  immature  striated  plumage  they 
resemble  the  mature  redpole  and  female  siskin,  as  well  as  the 
young  of  the  goldfinch,  greenfinch  and  some  other  allied 
species.  The  young  of  many  kinds  of  buntings  (Emberiza) 
resemble  one  another,  and  likewise  the  adult  states  of  the 
common  bunting,  E.  miliaria.  In  almost  the  whole  large 
group  of  thrushes  the  young  have  their  breasts  spotted — a 
character  which  is  retained  throughout  life  by  many 
species,  but  is  quite  lost  by  others,  as  by  the  Turdus 
migrator  ins.  So  again  with  many  thrushes,  the  feathers 
on  the  back  are  mottled  before  they  are  moulted  for  the 
first  time,  and  this  character  is  retained  for  life  by  certain 
eastern  species.  The  young  of  many  species  of  shrikes 
(Lanius),  of  some  woodpeckers  and  of  an  Indian  pigeon 
(Chalcophaps  indicus)  are  transversely  striped  on  the 
under  surface;  and  certain  allied  species  or  whole  genera 
are  similarly  marked  when  adult.  In  some  closely  allied 
and  resplendent  Indian  cuckoos  (Chrysococcyx)  the  mature 
species  differ  considerably  from  one  another  in  color,  but 
the  young  cannot  be  distinguished.  The  young  of  an 
Indian  goose  {^Sarkidiornis  melanonotus)  closely  resemble 
in  plumage  an  allied  genus,  Dendrocygna,  when  mature.* 

*  In  regard  to  thrushes,  shrikes  and  woodpeckers,  see  Mr.  Blyth, 
»  Charlesworth's  ''Mag.  of  Nat.   Hist.,"  vol.  i,  1837,  p.  304;  also 


530  THE  DESCENT  OF  MAN. 

Similar  facts  will  hei-^after  be  given  in  regard  to  certain 
herons.  Young  black  grouse  ( Tetrao  tetrix)  resemble  the 
young  as  well  as  the  old  of  certain  other  species,  for  in- 
stance, the  red  grouse  or  T.  scoHcus.  Finally,  as  Mr. 
Blytli,  who  has  attended  closely  to  this  subject,  has  well 
remarked,  the  natural  affinities  of  many  species  are  best 
exhibited  in  their  immature  plumage;  and  as  the  true 
affinities  of  all  organic  beings  depend  on  their  descent  from 
a  common  progenitor,  this  remark  strongly  confirms  the 
belief  that  the  immature  plumage  approximately  shows  us 
the  former  or  ancestral  condition  of  the  species. 

Although  many  young  birds  belonging  to  various  fami- 
lies thus  give  us  a  glimpse  of  the  plumage  of  their  remote 
progenitors,  yet  there  are  many  other  birds,  both  dull- 
colored  and  bright-colored,  in  which  the  young  closely 
resemble  their  parents.  In  such  cases  the  young  of  the 
different  species  cannot  resemble  each  other  more  closely 
than  do  the  parents;  nor  can  they  strikingly  resemble 
allied  forms  when  adult.  They  give  us  but  little  insight 
into  the  plumage  of  their  progenitors,  excepting  in  so  far 
that  when  the  young  and  the  old  are  colored  in  the  same 
general  manner  throughout  a  whole  group  of  species,  it  is 
probable  that  their  progenitors  were  similarly  colored. 

We  may  now  consider  the  classes  of  cases  under  which 
the  differences  and  resemblances  between  the  plumage  of 
the  young  and  the  old,  in  both  sexes  or  in  one  sex  alone, 
may  be  grouped.  Rules  of  this  kind  were  first  enounced 
by  Cuvier;  but  with  the  progress  of  knowledge  they  require 
some  modification  and  amplification.  This  I  have  at- 
tempted to  do,  as  far  as  the  extreme  complexity  of  the 
subject  permits,  from  information  derived  from  various 
sources;  but  a  full  essay  on  this  subject  by  some  competent 
ornithologist  is  much  needed.  In  order  to  ascertain  to 
what  extent  each  rule  prevails  I  have  tabulated  the  facts 
given  in  four  great  works,  namely,  by  Macgillivray  on  the 
birds  of  Britain,  Audubon  on  those  of  North  America, 
Jerdon  on  those  of  India,  and  Gould  on  those  of  Australia. 

foot-note  to  his  translation  of  Cuvier's  "  Regne  Animal,"  p.  159.  I 
give  the  case  of  Loxia  on  Mr.  Blytli's  information.  On  thrushes,  see 
also  Audubon,  "  Ornith.  Biography,"  vol.  ii,  p.  195.  On  Chryso- 
coccyx  and  Chalcophaps,  Blyth,  as  quoted  in  Jerdon's  "Birds  of 
India."  vol.  iii,  p.  485.  On  Sarkidiornis,  Blyth,  in  "Ibis,"  1867,  p, 
175. 


BIRDS.  531 

I  may  here  premise,  first,  that  the  several  cases  or  rules 
graduate  into  each  other ;  and  secondly,  that  when  the 
young  are  said  to  resemble  their  parents  it  is  not  meant 
that  they  are  identically  alike,  for  their  colors  are  almost 
always  less  vivid,  and  the  feathers  are  softer  and  often  of  a 
different  shape. 

RULES   OR   CLASSES   OF   CASES. 

I.  When  the  adult  male  is  more  beautiful  or  conspicuous 
than  the  adult  female,  the  young  of  both  sexes  in  their 
first  plumage  closely  resemble  the  adult  female,  as  with 
the  common  fowl  and  peacock;  or,  as  occasionally  occurs, 
they  resemble  her  much  more  closely  than  they  do  the 
adult  male. 

II.  When  the  adult  female  is  more  conspicuous  than 
the  adult  male,  as  sometimes,  though  rarely,  occurs,  the 
young  of  both  sexes  in  their  first  plumage  resemble  the 
adult  male. 

III.  When  the  adult  male  resembles  the  adult  female, 
the  young  of  both  sexes  have  a  peculiar  first  plumage  of 
their  own,  as  with  the  robin. 

IV.  When  the  adult  male  resembles  the  adult  female, 
the  young  of  both  sexes  in  their  first  plumage  resemble  the 
adults,  as  with  the  kingfisher,  many  parrots,  crows,  hedge- 
warblers. 

V.  W^hen  the  adult  of  both  sexes  have  a  distinct  winter 
and  summer  plumage,  whether  or  not  the  male  differs  from 
the  female,  the  young  resemble  the  adults  of  both  sexes  in 
their  winter  dress,  or  much  more  rarely  in  their  summer 
dress,  or  they  resemble  the  females  alone.  Or  the  young 
may  have  an  intermediate  character;  or  again  they  may 
differ  greatly  from  the  adults  in  both  their  seasonal 
plumages. 

VI.  In  some  few  cases  the  young  in  their  first  plumage 
differ  from  each  other  according  to  sex;  the  young  males 
resembling  more  or  less  closely  the  adult  males,  and  the 
young  females  more  or  less  closely  the  adult  females. 

Class  I. — In  this  class  the  young  of  both  sexes  more  or 
less  closely  resemble  the  adult  female,  while  the  adult  male 
differs  from  the  adult  female,  often  in  the  most  conspicu- 
ous manner.     Innumerable  instances  in  all  orders  could  bQ 


532  THE  DESCENT  OF  MAN. 

given;  it  will  suffice  to  call  to  mind  the  common  pheasant, 
(luck  and  house-sparrow.  The  cases  under  this  class  gradu- 
ate into  others.  Thus  the  two  sexes  when  adult  may  differ 
BO  slightly,  and  the  young  so  slightly  from  the  adults,  that 
it  is  doubtful  whether  such  cases  ought  to  come  under  the 
present,  or  under  the  third  or  fourth  classes.  So,  again, 
the  young  of  the  two  sexes,  instead  of  being  quite  alike, 
may  differ  in  a  slight  degree  from  each  other,  as  in  our 
sixth  class.  These  transitional  cases,  however,  are  few, 
or  at  least  are  not  strongly  pronounced,  in  comparison  with 
those  which  come  strictly  under  the  present  class. 

The  force  of  the  present  law  is  well  shown  in  those 
groups,  in  which,  as  a  general  rule,  the  two  sexes  and  the 
young  are  all  alike;  for  when  in  these  groups  the  male  does 
differ  from  the  female,  as  with  certain  parrots,  kingfishers, 
pigeons,  etc.,  the  young  of  both  sexes  resemble  the 
adult  female.*  We  see  the  same  fact  exhibited  still 
more  clearly  in  certain  anomalous  cases;  thus  the  male  of 
HelioVirix  auriculata  (one  of  the  humming-birds)  differs 
conspicuously  from  the  female  in  having  a  splendid  gorget 
and  fine  ear-tufts,  but  the  female  is  remarkable  from 
having  a  much  longer  tail  than  that  of  the  male;  now  the 
young  of  both  sexes  resemble  (with  the  exception  of  the 
breast  being  spotted  with  bronze)  the  adult  female  in  all 
other  respects,  including  the  length  of  her  tail,  so  that  the 
tail  of  the  male  actually  becomes  shorter  as  he  reaches 
maturity,  which  is  a  most  unusual  circumstance,  f  Again, 
the  plumage  of  the  male  goosander  (Mergus  mergansei')  is 
more  conspicuously  colored  than  that  of  the  female,  with 
the  scapular  and  secondary  wing- feathers  much  longer;  but 

*  See,  for  instance,  Mr.  Gould's  account  ("  Hand-book  to  the  Birds 
of  Australia,"  vol.  i,  p.  133)  of  Cyanalcyon  (one  of  the  kingfishers), 
in  which,  however,  the  young  male,  though  resembling  the  adult 
female,  is  less  brilliantly  colored.  In  some  species  of  Dacelo  the 
males  have  blue  tails,  and  the  females  brown  ones;  and  Mr.  R.  B. 
Sharpe  informs  me  that  the  tail  of  the  young  male  of  D.  gmtdichaudi 
is  at  first  brown.  Mr.  Gould  has  described  (ibid,  vol.  ii,  pp.  14,  20, 
37)  the  sexes  and  the  young  of  certain  black  cockatoos  and  of  the 
King  Lory,  with  which  the  same  rule  prevails.  Also  Jerdon  ("  Birds 
of  India,"  vol.  i,  p.  260)  on  the  Palceornis  rosa,  in  which  the  young 
are  more  like  the  female  than  the  male.  See  Audubon  ("  Ornith. 
Biograph.,"  vol.  ii,  p.  475)  on  the  two  sexes  and  the  young  of  Co- 
lumba  passerina. 

f  I  owe  this  information  to  Mr.  Gould,  who  showed  me  the  speci- 
mens; see  also  his  "  Introduction  to  the  Trochilidae,"  1861,  p.  120. 


BIRDS.  533 

differently  from  what  occurs,  as  far  as  I  know  in  any  other 
bird,  the  crest  of  the  adult  male,  though  broader  than  that 
of  the  female,  is  considerably  shorter,  being  only  a  little 
above  an  inch  in  length;  the  crest  of  the  female  being  two 
and  a  half  inches  long.  Now  the  young  of  both  sexes 
entirely  resemble  the  adult  female,  so  that  their  crests  are 
actually  of  greater  length,  though  narrower  than  in  the 
adult  male.* 

When  the  young  and  the  females  closely  resemble  each 
other  and  both  differ  from  the  males,  the  most  obvious  con- 
clusion is  that  the  males  alone  have  been  modified.  Even 
in  the  anomalous  cases  of  the  Heliothrix  and  Mergus,  it  is 
probable  that  originally  both  adult  sexes  were  furnished — 
the  one  species  with  a  much  elongated  tail  and  the  other 
with  a  much  elongated  crest — these  characters  having  since 
been  partially  lost  by  the  adult  males  from  some  unexplained 
cause,  and  transmitted  in  their  diminished  state  to  their 
male  offspring  alone,  when  arrived  at  the  corresponding 
age  of  maturity.  The  belief  that  in  the  present  class  the 
male  aloin  has  been  modified,  as  far  as  the  differences 
between  the  male  and  the  female  together  with  her  young 
are  concerned,  is  strongly  supported  by  some  remarkable 
facts  recorded  by  Mr.  Blyth,t  with  respect  to  closely  allied 
species  which  represent  each  other  in  distinct  countries. 
For  with  several  of  these  representative  species  the  adult 
males  have  undergone  a  certain  amount  of  change  and  can 
be  distinguished;  the  females  and  the  young  from  the  dis- 
tinct countries  being  indistinguishable,  and  therefore 
absolutely  unchanged.  This  is  the  case  with  certain 
Indian  chats  (Thamnobia),  with  certain  honey-suckers  (Nec- 
tarinia),  shrikes  (Tephrodornis),  certain  kingfishers  (Tany- 
siptera),  Kalij  pheasants  (Gallophasis)  and  tree-partridges 
(Arboricola). 

In  some  analogous  cases,  namely,  with  birds  having  a 
different  summer  and  winter  plumage,  but  with  the  two  sexes 
nearly  alike,  certain  closely  allied  species  can  easily  be  dis- 
tinguished in   their  summer  or  nuptial  plumage,  yet  are 

*  Macgillivray,  '•  Hist.  Brit.  Birds,"  vol.  v,  pp.  207,  214. 

t  See  his  admirable  paper  in  the  "Journal  of  tlie  Asiatic  Soc.  of 
Bengal,"  vol  xix.  1850,  p.  223;  see  also  Jerdon,  "  Birds  of  India," 
vol.  i,  introduction,  p.  29.  In  regard  to  Tanysiptera,  Prof.  Sclilegel 
told  Mr.  Blytb  that  he  could  distinguish  several  distinct  races,  solely 
by  comparing  the  adult  males. 


534  THE  DESCENT  OF  MAN, 

indistinguishable  in  their  winter  as  well  as  in  their  imma- 
ture plumage.  This  is  the  case  with  some  of  the  closely 
allied  Indian  wag-tails  or  Motacillae.  Mr.  Swinhoe  * 
informs  me  that  three  species  of  Ardeola,  a  genus  of 
herons,  which  represent  one  another  on  separate  conti- 
nents, are  '*  most  strikingly  different  "  when  ornamented 
with  their  summer  plumes,  but  are  hardly,  if  at  all,  dis- 
tinguishable during  the  winter.  The  young  also  of  these 
three  species  in  their  immature  plumage  closely  resemble 
the  adults  in  their  winter  dress.  This  case  is  all  the 
more  interesting,  because  with  two  other  species  of  Ardeola 
both  sexes  retain,  during  the  winter  and  summer,  nearly 
the  same  plumage  as  that  possessed  by  the  three  first  spe- 
cies during  the  winter  and  in  their  immature  state;  and 
this  plumage,  which  is  common  to  several  distinct  species 
at  different  ages  and  seasons,  probably  shows  us  how  the 
progenitors  of  the  genus  were  colored.  In  all  these  cases, 
the  nuptial  plumage  which  we  may  assume  was  originally 
acquired  by  the  adult  males  during  the  breeding-season, 
and  transmitted  to  the  adults  of  both  sexes  at  the  corre- 
si3onding  season,  has  been  modified,  while  the  winter  and 
immature  plumages  have  been  left  unchanged. 

The  question  naturally  arises,  how  is  it  that  in  these 
latter  cases  the  winter  plumage  of  both  sexes,  and  in 
the  former  cases  the  plumage  of  the  adult  females,  as 
well  as  the  immature  plumage  of  the  young,  have  not  been 
at  all  affected?  The  species  which  represent  each  other  in 
distinct  countries  will  almost  always  have  been  exposed  to 
somewhat  different  conditions,  but  we  can  hardly  attribute 
to  tliis  action  the  modification  of  the  plumage  in  the  males 
alone,  seeing  that  the  females  and  the  young,  though  simi- 
larly exposed,  have  not  been  affected.  Hardly  any  fact 
shows  us  more  clearly  how  subordinate  in  importance  is 
the  direct  action  of  the  conditions  of  life,  in  comparison 
with  the  accumulation  through  selection  of  indefinite  vari- 
ations, than  the  surprising  difference  between  the  sexes  of 
many  birds;  for  both  will  have  consumed  the  same  food, 
and  have  been  exposed  to  the  same  climate.  Nevertheless 
we  are  not  precluded  from  believing  that  in  the  course  of 

*See  also  Mr.  Swinhoe,  in  "Ibis,"  July,  1863,  p.  131;  and  a  pre- 
vious paper,  with  an  extract  from  a  note  by  Mr.  Blyth,  in  "  Ibis," 
Jan.  1861,  p.  24. 


BmD8.  535 

time  new  conditions  may  produce  some  direct  effect  either 
on  both  sexes,  or  from  their  constitutional  differences 
chiefly  on  one  sex.  We  see  only  that  this  is  subordinate  in 
importance  to  the  accumulated  results  of  selection.  Judg- 
ing, however,  from  a  wide-spread  analogy,  when  a  species 
migrates  into  a  new  country  (and  this  must  precede  the 
formation  of  representative  species),  the  changed  condi- 
tions to  which  they  will  almost  always  have  been  exposed 
will  cause  them  to  undergo  a  certain  amount  of  fluctuating 
variability.  In  this  case  sexual  selection,  which  depends 
on  an  element  liable  to  change — the  taste  or  admiration  of 
the  female — will  have  had  new  shades  of  color  or  other  dif- 
ferences to  act  on  and  accumulate;  and  as  sexual  selection 
is  always  at  work,  it  would  (from  what  we  know  of  the 
results  on  domestic  animals  of  man's  unintentional  selec- 
tion), be  surprising  if  animals  inhabiting  separate  districts, 
which  can  never  cross  and  thus  blend  their  newly  acquired 
characters,  were  not,  after  a  sufficient  lapse  of  time,  differ- 
ently modified.  These  remarks  likewise  apply  to  the 
nuptial  or  summer  plumage,  whether  confined  to  the  males 
or  common  to  both  sexes. 

Although  the  females  of  the  above  closely  allied  or  rep- 
resentative species,  together  with  their  young,  differ  hardly 
at  all  from  one  another,  so  that  the  males  alone  can  be  dis- 
tinguished, yet  the  females  of  most  species  within  the  same 
genus  obviously  differ  from  each  other.  The  differences, 
however,  are  rarely  as  great  as  between  the  males.  AVe  see 
this  clearly  in  the  whole  family  of  the  Gallinaceae ;  the 
females,  for  instance,  of  the  common  and  Japan  pheasant, 
and  especially  of  the  gold  and  Amherst  pheasant — of  the 
silver  pheasant  and  the  wild  fowl — resemble  one  another 
very  closely  in  color,  while  the  males  differ  to  an  extraor- 
dinary degree.  So  it  is  with  the  females  of  most  of  the 
Cotingidae,  Fringillidae,  and  many  other  families.  There 
can  indeed  be  no  doubt  that,  as  a  general  rule,  the  females 
have  been  less  modified  than  the  males.  Some  few  birds, 
however,  offer  a  singular  and  inexplicable  exception;  thus 
the  females  of  Paradisea  apoda  and  P.  popuana  differ  from 
each  other  more  than  do  their  respective  males;*  the  female 
of  the  latter  species  having  the  under  surface  pure  white, 
while  the  female  P.  apoda  is  deep  brown  beneath.      So, 

*  Wallace,  "  The  Malay  Archipelago,"  vol.  ii,  1869,  p.  394. 


536  THE  DESCENT  OF  MAN. 

again,  as  I  hear  from  Prof.  Newton,  the  males  of  two 
species  of  Oxynotus  (shrikes),  which  represent  each  other  in 
the  Islands  of  Mauritius  and  Bourbon,*  differ  but  little  in 
color,  while  the  females  differ  much.  In  the  Bourbon 
species  the  female  appears  to  have  partially  retained  an 
immature  condition  of  plumage,  for  at  first  sight  she 
*' might  be  taken  for  the  young  of  the  Mauritian  species.'" 
These  differences  may  be  compared  with  those  inexplicable 
ones  which  occur  independently  of  man's  selection  in 
certain  sub-breeds  of  the  game-fowl,  in  which  the  females 
are  very  different,  while  the  males  can  hardly  be  distin- 
guished, f 

As  I  account  so  largely  by  sexual  selection  for  the  differ- 
ences between  the  males  of  allied  species,  how  can  the 
differences  between  the  females  be  accounted  for  in  all 
ordinary  cases?  We  need  not  here  consider  the  species 
which  belong  to  distinct  genera;  for  with  these,  adaptation 
to  different  habits  of  life,  and  other  agencies,  will  have 
come  into  play.  In  regard  to  the  differences  between  the 
females  within  the  same  genus  it  appears  to  me  almost  cer- 
tain, after  looking  through  various  large  groups,  that  the 
chief  agent  has  been  the  greater  or  less  transference  to  the 
female  of  the  characters  acquired  by  the  males  through 
sexual  selection.  In  the  several  British  finches  the  two 
sexes  dift'er  either  very  slightly  or  considerably;  and  if  we 
compare  the  females  of  the  greenfinch,  chaffinch,  goldfinch, 
bullfinch,  crossbill,  sparrow,  etc.,  we  shall  see  that  they 
differ  from  one  another  chiefly  in  the  points  in  which  they 
partially  resemble  their  respective  males;  and  the  colors  of 
the  males  may  safely  be  attributed  to  sexual  selection. 
With  many  gallinaceous  species  the  sexes  differ  to  an 
extreme  degree,  as  with  the  peacock,  pheasant  and  fowl, 
while  with  other  species  there  has  been  a  partial  or  even 
complete  transference  of  character  from  the  male  to  the 
female.  The  females  of  the  several  species  of  Polyplectron 
exhibit  in  a  dim  condition,  and  chiefly  on  the  tail,  the 
splendid  ocelli  of  their  males.  The  female  partridge  diff'ers 
from  the  male  only  in  the  red  mark  on  her  breast  being 
smaller;  and  the  female  wild  turkey  only  in  her  colors  being 

*  These  species  are  described  with  colored  figures,  by  M.  F.  Pollen, 
in  "  Ibis,"  1866,  p.  275. 
f  "  Variation  of  Animals,  etc.,  under  Domestication,"  vol.  i,  p.  251. 


BIEDS.  637 

mnch  duller.  In  the  guinea-fowl  the  two  sexes  are  indis- 
tinguishable. There  is  no  improbability  in  the  plain, 
though  peculiarly  spotted,  plumage  of  this  latter  bird 
having  been  acquired  through  sexual  selection  by  the 
males,  and  then  transmitted  to  both  sexes;  for  it  is  not 
essentially  different  from  the  much  more  beautifully 
spotted  plumage,  characteristic  of  the  males  alone  of  the 
Tragopan  pheasants. 

It  should  be  observed  that  in  some  instances  the  trans- 
ference of  characters  from  the  male  to  the  female  has  been 
effected  apparently  at  a  remote  period,  the  male  having 
subsequently  undergone  great  changes  without  transferring 
to  the  female  any  of  his  later  gained  characters.  For  in- 
stance, the  female  and  the  young  of  the  black  grouse 
(Tetrao  tetrix)  resemble  pretty  closely  both  sexes  and  the 
young  of  the  red  grouse  {T.  scoticus);  and  we  may  conse- 
quently infer  that  the  black  grouse  is  descended  from  some 
ancient  species,  of  which  both  sexes  were  colored  in  nearly 
the  same  manner  as  the  red  grouse.  As  both  sexes  of  this 
latter  species  are  more  distinctly  barred  during  the  breed- 
ing-season than  at  any  other  time,  and  as  the  male  differs 
slightly  from  the  female  in  his  more  strongly  pronounced 
red  and  brown  tints,*  we  may  conclude  that  his  plumage 
has  been  influenced  by  sexual  selection,  at  least  to  a  certain 
extent.  If  so,  we  may  further  infer  that  the  nearly  similar 
plumage  of  the  female  black  grouse  was  similarly  produced 
at  some  former  period.  But  since  this  period  the  male 
black  grouse  has  acquired  his  fine  black  plumage  with  his 
forked  and  outwardly  curled  tail-feathers;  but  of  these  char- 
acters there  has  hardly  been  any  transference  to  the  female, 
excepting  that  she  shows  in  her  tail  a  trace  of  the  curved 
fork. 

We  may  therefore  conclude  that  the  females  of  distinct 
though  allied  species  have  often  had  their  plumage  rendered 
more  or  less  different  by  the  transference  of  various  degrees 
of  characters  acquired  by  the  males  through  sexual  selec- 
tion both  during  former  and  recent  times.  But  it  deserves 
especial  attention  that  brilliant  colors  have  been  transferred 
much  more  rarely  than  other  tints.  For  instance,  the 
male  of  the  red-throated  blue-breast  (Cyanecula  suecica) 
has  a  rich  blue  breast,  including  a  sub- triangular  red  mark; 

♦Macgillivray,  "Hist.  British  Birds."  vol.  i,  pp.  172-174. 


538  THE  nmSCBKT  OF  MAN, 

now  marks  of  nearly  the  same  shape  have  been  transferred 
to  the  female,  but  the  central  space  is  fulvous  instead  of 
red  and  is  surrounded  by  mottled,  instead,  of  blue  feathers. 
The  Gallinaceae  otfer  many  analogous  cases;  for  none  of 
the  species,  such  as  partridges,  quails,  guinea-fowl,  etc., 
in  which  the  colors  of  the  plumage  have  been  largely  trans- 
ferred from  the  male  to  the  female,  are  brilliantly  colored. 
This  is  well  exemplified,  with  the  pheasants,  in  which  the 
male  is  generally  so  much  more  brilliant  than  the  female; 
but  with  the  eared  and.  cheer  pheasants  (Crossoplilon 
mcrifum  and  Pliasianus  ivallichii)  the  sexes  closely  resem- 
ble each  other  and  their  colors  are  dull.  We  may  go  so 
far  as  to  believe  that  if  any  part  of  the  plumage  in  the 
males  of  these  two  pheasants  had  been  brilliantly  colored 
it  would  have  been  transferred  to  the  females.  These  facts 
strongly  support  Mr.  Wallace^s  view  that  with  birds  which 
are  exposed  to  much  danger  during  incubation,  the  trans- 
ference of  bright  colors  from  the  male  to  the  female  has 
been  checked  through  natural  selection.  We  must  not, 
however,  forget  that  another  explanation,  before  given,  is 
possible;  namely,  that  the  males  which  varied  and  became 
bright,  while  they  were  young  and  inexperienced,  would 
have  been  exposed  to  much  danger  and  would  generally 
have  been  destroyed;  the  older  and  more  cautious  males,  on 
the  other  hand,  if  they  varied  in  a  like  manner,  would  not 
only  have  been  able  to  survive,  but  would  have  been 
favored  in  their  rivalry  with  other  males.  Now  variations 
occurring  late  in  life  tend  to  be  transmitted  exclusively  to 
the  same  sex,  so  that  in  this  case  extremely  bright  tints 
would  not  have  been  transmitted  to  the  females.  On  the 
other  hand,  ornaments  of  a  less  conspicuous  kind,  such  as 
those  possessed  by  the  eared  and  cheer  pheasants,  would  not 
have  been  dangerous,  and  if  they  appeared  during  early 
youth  would  generally  have  been  transmitted  to  both 
sexes. 

In  addition  to  the  effects  of  the  partial  transference  of 
characters  from  the  males  to  the  females  some  of  the  differ- 
ences between  the  females  of  closely  allied  species  may  be 
attributed  to  the  direct  or  definite  action  of  the  conditions 
of  life.*     With  the  males  any  such  action  would  generally 

*  See,  on  this  subject,  chap,  xxiii,  in  the  "Variation  of  Animals 
and  Plants  under  Domestication." 


BIRDS.  539 

have  been  masked  by  the  brilliant  colors  gained  through 
sexual  selection;  but  not  so  with  the  females.  Each  of  the 
endless  diversities  in  plumage  which  we  see  in  our  domes- 
ticated birds  is,  of  course,  the  result  of  some  definite  cause; 
and,  under  natural  and  more  uniform  conditions,  some  one 
tint,  assuming  that  it  was  in  no  way  injurious,  would  almost 
certainly  sooner  or  later  prevail.  The  free  intercrossing  of 
the  many  individuals  belonging  to  the  same  species  would 
ultimately  tend  to  make  any  change  of  color  thus  induced 
uniform  in  character. 

No  one  doubts  that  both  sexes  of  many  birds  have  had 
their  colors  adapted  for  the  sake  of  protection;  and  it  is 
possible  that  the  females  alone  of  some  species  may  have 
been  modified  for  this  end.  Although  it  would  be  a  difficult, 
perhaps  an  impossible,  process,  as  shown  in  the  last  chapter, 
to  convert  one  form  of  transmission  into  another  through 
selection,  there  would  not  be  the  least  difficulty  in  adapting 
the  colors  of  the  female,  independently  of  those  of  the  male, 
to  surrounding  objects,  through  the  accumulation  of  varia- 
tions which  were  from  the  first  limited  in  their  transmission 
to  the  female  sex.  If  the  variations  were  not  thus  limited 
the  bright  tints  of  the  male  would  be  deteriorated  or  de- 
stroyed. Whether  the  females  alone  of  many  species  have 
been  thus  specially  modified  is  at  present  very  doubtful. 
I  wish  I  could  follow  Mr.  Wallace  to  the  full  extent; 
for  the  admission  would  remove  some  difficulties.  Any 
variations  which  were  of  no  service  to  the  female  as  a 
protection  would  be  at  once  obliterated,  instead  of  being 
lost  simply  by  not  being  selected,  or  from  free  intercross- 
ing, or  from  being  eliminated  when  transferred  to  the  male 
and  in  any  way  injurious  to  him.  Thus  the  plumage  of  the 
female  would  be  kept  constant  in  character.  It  would  also 
be  a  relief  if  we  could  admit  that  the  obscure  tints  of  both 
sexes  of  many  birds  had  been  acquired  and  preserved  for  the 
sake  of  protection,  for  example,  of  the  hedge- warbler  or  kitty- 
wren  (Accentor  modular  is  and  Troglodytes  vulgaris),  with 
respect  to  which  we  have  no  sufficient  evidence  of  the 
action  of  sexual  selection.  We  ought,  however,  to  be  cau- 
tious in  concluding  that  colors  which  appear  to  us  dull 
are  not  attractive  to  the  females  of  certain  species;  we 
should  bear  in  mind  such  cases  as  that  of  the  common 
house-sparrow,  in  which  the  male  differs  much  from  the 
female,  but  does  not  exhibit  any  bright  tints.     No  one 


§40  THE  DESCENT  O'F  MA^. 

probably  will  dispute  that  many  gallinaceous  birds  Avbicb 
live  on  the  open  ground  have  acquired  their  present 
colors,  at  least  in  part,  for  the  sake  of  protection.  We 
know  how  well  they  are  thus  concealed  ;  we  know  that 
ptarmigans,  while  changing  from  their  winter  to  their 
summer  plumage,  both  of  which  are  protective,  suffer 
greatly  from  birds  of  prey.  But  can  we  believe  that  the 
very  slight  differences  in  tints  and  markings  between,  for 
instance,  the  female  black-grouse  and  red-grouse  serve  as  a 
protection?  Are  partridges,  as  they  are  now  colored, 
better  protected  than  if  they  had  resembled  quails?  Do  the 
slight  differences  between  the  females  of  the  common 
pheasant,  the  Japan  and  gold  pheasants,  serve  as  a  pro- 
tection, or  might  not  their  plumages  have  been  inter- 
changed with  impunity?  From  what  Mr.  Wallace  has 
observed  of  the  habits  of  certain  gallinaceous  birds  in  the 
east,  he  thinks  that  such  slight  differences  are  beneficial. 
For  myself,  I  will  only  say  that  I  am  not  convinced. 

Formerly  when  I  was  inclined  to  lay  much  stress  on  pro- 
tection as  accounting  for  the  duller  colors  of  female  birds, 
it  occurred  to  me  that  possibly  both  sexes  and  the  young 
might  aboriginally  have  been  equally  bright  colored  ;  but 
that  subsequently,  the  females  from  the  danger  incurred 
during  incubation,  and  the  young  from  being  inexperienced, 
had  been  rendered  dull  as  a  protection.  But  this  view  is 
not  supported  by  any  evidence,  and  is  not  probable;  for 
we  thus  in  imagination  expose  during  past  times  the 
females  and  the  young  to  danger,  from  which  it  has  sub- 
sequently been  necessary  to  shield  their  modified  descend- 
ants. We  have,  also,  to  reduce,  through  a  gradual  process 
of  selection,  the  females  and  the  young  to  almost  exactly 
the  same  tints  and  markings,  and  to  transmit  them  to  the 
corresponding  sex  and  period  of  life.  On  tlie  supposition 
that  the  females  and  the  young  have  partaken  during  each 
stage  of  the  process  of  modification  of  a  tendency  to  be  as 
brightly  colored  as  the  males,  it  is  also  a  somewhat  strange 
fact  that  the  females  have  never  been  rendered  dull  colored 
without  the  young  participating  in  the  same  change;  for 
there  are  no  instances,  as  far  as  I  can  discover,  of  species 
with  the  females  dull  and  the  young  bright  colored.  A 
partial  exception,  however,  is  offered  by  the  young  of  cer- 
tain woodpeckers,  for  they  have  "  the  whole  upper  part  of 
the  head  tinged  with  red,"  which  afterward  either  decreases 


BIRDS.  541 

into  a  mere  circular  red  line  in  the  adults  of  both  sexes,  or 
quite  disappears  in  the  adult  females.* 

Finally,  with  respect  to  our  present  class  of  cases,  the 
most  probable  view  appears  to  be  that  successive  variations 
in  brightness  or  in  other  ornamental  characters  occurring 
in  tlie  males  at  a  rather  late  period  of  life  have  alone  been 
preserved;  and  that  most  or  all  of  these  variations,  owing 
to  the  late  period  of  life  at  which  they  appeared, 
have  been  from  the  first  transmitted  only  to  the  adult  male 
offspring.  Any  variations  in  brightness  occurring  in  the 
females  or  in  the  young  would  have  been  of  no  service  to 
them,  and  would  not  have  been  selected;  and  moreover,  if 
dangerous  would  have  been  eliminated.  Thus  the  females 
and  the  young  will  either  have  been  left  unmodified,  or 
(as  is  much  more  common)  will  have  been  partially  modi- 
fied by  receiving  through  transference  from  the  males  some 
of  his  successive  variations.  Both  sexes  have  perhaps  been 
directly  acted  on  by  the  conditions  of  life  to  which  they 
have  long  been  exposed;  but  the  females  from  not  being 
otherwise  much  modified  will  best  exhibit  any  such  effects. 
These  changes  and  all  others  will  have  been  kept  uniform 
by  the  free  intercrossing  of  many  individuals.  In  some 
cases,  especially  with  ground  birds,  the  females  and  the 
young  may  possibly  have  been  modified,  independently  of 
the  males,  for  the  sake  of  protection  so  as  to  have  acquired 
the  same  dull-colored  plumage. 

Class  II.  When  the  adult  female  is  more  conspicuous 
than  the  adult  male  the  young  of  both  sexes  in  their  first 
plumage  resemble  the  adult  male. — This  class  is  exactly  the 
reverse  of  the  last,  for  the  females  are  here  brighter  colored 
or  more  conspicuous  than  the  males;  and  the  young,  as  far 
as  they  are  known,  resemble  the  adult  males  instead  of  the 
adult  females.  But  the  difference  between  the  sexes  is 
never  nearly  so  great  as  with  many  birds  in  the  first  class, 
and  the  cases  are  comparatively  rare.  Mr.  Wallace,  who 
first  called  attention  to  the  singular  relation  which  exists 
between  the  less  bright  colors  of  the  males  and  their  per- 
forming the  duties  of  incubation,  lays  great  stress  on  this 

♦Audubon,  "Omith,  Biography,"  vol.  i,  p.  193.  Macgillivray, 
**  Hist.  Brit.  Birds,"  vol  iii,  p.  85.  See  also  the  case  before  given  of 
Indopicus  carlotta. 


542  THE  DESCENT  OF  MAN, 

point*  as  a  crucial  test  that  obscure  colors  have  been  ac- 
quired for  the  sake  of  protection  during  the  period  of  nest- 
ing. A  different  view  seems  to  me  more  probable.  As 
the  cases  are  curious  and  not  numerous  I  will  briefly  give 
all  that  1  have  been  able  to  find. 

In  one  section  of  the  genus  Turnix,  quail-like  birds,  the 
female  is  invariably  larger  than  the  male  (being  nearly 
twice  as  large  in  one  of  the  Australian  species),  and  this  is 
an  unusual  circumstance  with  the  Gallinaceae.  In  most  of 
the  species  the  female  is  more  distinctly  colored  and 
brighter  than  the  male,f  but  in  some  few  species  the  sexes 
are  alike.  In  Turnix  taigoor  of  India  the  male  ^'  wants 
the  black  on  the  throat  and  neck,  and  the  whole  tone  of 
the  plumage  is  lighter  and  less  pronounced  than  that  of 
the  female."  The  female  appears  to  be  noisier,  and  is  cer- 
tainly much  more  pugnacious  than  the  male;  so  that  the 
females  and  not  the  males  are  often  kept  by  the  natives  for 
fighting,  like  gamecocks.  As  male  birds  are  exposed  by 
the  English  bird-catchers  for  a  decoy  near  a  trap,  in  order 
to  catch  other  males  by  exciting  their  rivalry,  so  the  females 
of  this  Turnix  are  employed  in  India.  When  thus  ex- 
posed the  females  soon  begin  their  ^Houd,  purring  call, 
which  can  be  heard  a  long  way  off,  and  any  females  within 
ear-shot  run  rapidly  to  the  spot  and  commence  fighting 
with  the  caged  bird."  In  this  way  from  twelve  to  twenty 
birds,  all  breeding-females,  may  be  caught  in  tlie  course  of 
a  single  day.  Tlie  natives  assert  that  the  females  after 
laying  their  eggs  associate  in  flocks,  and  leave  the  males  to 
sit  on  them.  There  is  no  reason  to  doubt  the  truth 
of  this  assertion,  which  is  supported  by  some  observa- 
tions made  in  China  by  Mr.  Swinhoe.j;  Mr.  Blyth 
believes  that  the  young  of  both  sexes  resemble  the  adult 
male. 

The  females  of  the  three  species  of  painted  snipes 
(Rhynchaea,  fig.  62)  "^are  not  only  larger  but  much  more 

*  "  Westminster  Review,"  July,  1867,  and  A.  Murray,  "Journal 
of  Travel,"  1868,  p.  83. 

•f-For  the  Australian  species,  see  Gould's  "  Hand-book,"  etc.,  vol. 
ii,  pp.  178,  180,  186,  188.  In  the  British  Museum  specimens  of  the 
Australian  Plain- wanderer  {Pedionomus  torqitatus)  may  be  seen, 
showing  similar  sexual  differences. 

t  Jerdon,  "Birds  of  India,"  vol.  iii,  p.  596.  Mr.  Swinhoe,  in 
"  Ibis,"  1865,  p.  543;  1866,  pp.  131,  405, 


BIRDS 


543 


richly  colored  than  the  males."  *  With  all  other  birds  in 
which  the  trachea  differs  in  structure  in  the  two  sexes  it  is 
more  developed  and  complex  in  the  male  than  in  the 
female;  but  in  the  UhyiichcBa  australis  it  is  simple  in  the 
male,  while  in  the  female  it  makes  four  distinct  convolu- 


Fig.  62.    Bhynchsea  capensis  (from  Brehm). 


tions  before  entering  the  lungs.  \  The  female,  therefore, 
of  this  species  has  acquired  an  eminently  masculine  char- 
acter. Mr.  Blyth  ascertained,  by  examining  many  speci- 
mens, that  the  trachea  is  not  convoluted  in  either  sex  of 
R.  hengalensis,  which  species  resembles  R.  australis  so 
closely  that  it  can  hardly  be  distinguished  except  by  its 
shorter  toes.     This  fact  is  another  striking  instance  of  the 

*  Jerdon,  "Birds  of  India,"  vol.  iii,  p.  677. 

\  Gould's  "  Hand-book  to  the  Birds  of  Australia,"  vol.  ii,  p.  275. 


544  THE  DESCENT  OF  MAN. 

law  that  secondary  sexual  characters  are  often  widely  dif- 
ferent in  closely  allied  forms,  though  it  is  a  very  rare  cir- 
cumstance when  such  diiferences  relate  to  the  female  sex. 
The  young  of  both  sexes  of  R.  bengalensis  in  their  first 
plumage  are  stiid  to  resemble  the  mature  male.*  There  is 
also  reason  to  believe  that  the  male  undertakes  the  duty  of 
incubation,  for  Mr.  Swinhoe  \  found  the  females  before  the 
close  of  the  summer  associated  in  flocks,  as  occurs  with  the 
females  of  the  turnix. 

The  females  of  Phalaropusfnlicarius  and  P.  hyperhoreus 
are  larger,  and  in  their  summer  plumage  "  more  gayly 
attired  than  the  males.''  But  the  difference  in  color  between 
the  sexes  is  far  from  conspicuous.  According  to  Prof.  Steen- 
strup,  the  male  alone  of  P.  fulicarins  undertakes  the  duty  of 
incubation;  this  is  likewise  shown  by  the  state  of  his 
breast-feathers  during  the  breeding-season.  The  female  of 
the  dotterel  plover  (Eudromias  morineUus)  is  larger  than 
the  male,  and  has  the  red  and  black  tints  on  the  lower  sur- 
face, the  white  crescent  on  the  breast  and  the  stripes  over 
the  eyes  more  strongly  pronounced.  The  male  also  takes 
at  least  a  share  in  hatching  the  eggs;  but  the  female  like- 
wise attends  to  the  young.  J  I  have  not  been  able  to  dis- 
cover whether  with  these  species  the  young  resemble  the 
adult  males  more  closely  than  the  adult  females;  for  the 
comparison  is  somewhat  difficult  to  make  on  account  of  the 
double  moult. 

Turning  now  to  the  ostrich  order  ;  the  male  of  the 
common  c^is&owoxy  {Casurius  galeatus)  vfo\\\d  be  thought 
by  any  one  to  be  the  female,  from  his  smaller  size  and  from 
the  appendages  and  naked  skin  about  his  head  being  much 
less  brightly  colored;  and  I  am  informed  by  Mr.  Bartlett 
that  in  the  Zoological  Gardens  it  is  certainly  the  male  alone 

*'*The  Indian  Field,"  Sept.,  1858,  p.  8. 

t  "  Ibis,"  1866,  p.  298. 

JFor  these  several  statements,  see  Mr.  Gould's  "Birds  of  Great 
Britain."  Prof.  Newton  informs  me  that  he  has  long  been  convinced, 
from  his  own  observations  and  from  those  of  others,  that  the  males 
of  the  above-named  species  take  either  the  whole  or  a  large  share  of 
the  duties  of  incubation,  and  that  they  "show  much  greater  devo- 
tion toward  their  young,  when  in  danger,  than  do  the  females."  So 
it  is,  as  he  informs  me,  with  Limosa  Inpponka  and  some  few  other 
waders,  in  which  the  females  are  larger  and  have  more  strongly  con- 
trasted colors  than  the  males. 


BIRDS.  545 

who  sits  on  the  eggs  and  takes  care  of  the  young.*  The 
female  is  said  by  Mr.  T.  W.  Wood  f  to  exhibit  during  the 
breeding-season  a  most  pugnacious  disposition  ;  and  her 
wattles  then  become  enlarged  and  more  brilliantly  colored. 
So  again  the  female  of  one  of  the  emus  {Dromceus  irroratus) 
is  considerably  larger  than  the  male,  and  she  possesses  a  slight 
top-knot,  but  is  otherwise  indistinguishable  in  plumage. 
She  appears,  however,  "  to  have  greater  power,  when  angry 
or  otherwise  excited,  of  erecting,  like  a  turkey-cock,  the 
feathers  of  her  neck  and  breast.  She  is  usually  the  more 
courageous  and  pugilistic.  She  makes  a  deep,  hollow,  gut- 
tural boom  especially  at  night,  sounding  like  a  small  gong. 
The  male  has  a  slenderer  frame  and  is  more  docile,  with  no 
voice  beyond  a  suppressed  hiss  when  angry,  or  a  croak." 
He  not  only  performs  the  whole  duty  of  incubation,  but 
has  to  defend  the  young  from  their  mother;  ''  for  as  soon 
as  she  catches  sight  of  her  progeny  she  becomes  violently 
agitated,  and  notwithstanding  the  resistance  of  the  father 
appears  to  use  her  utmost  endeavors  to  destroy  them.  For 
months  afterward  it  is  unsafe  to  put  the  parents  together, 
violent  quarrels  being  the  inevitable  result,  in  which  the 
female  generally  comes  off  conqueror."];  So  that  with  this 
emu  we  have  a  complete  reversal  not  only  of  the  parental 
and  incubating  instincts,  but  of  the  usual  moral  qualities  of 
the  two  sexes;  the  females  being  savage,  quarrelsome  and 
noisy,  the  males  gentle  and  good.  The  case  is  very  dif- 
ferent with  the  African  ostrich,  for  the  male  is  somewhat 
larger  than  the  female  and  has  finer  plumes,  with  more 
strongly  contrasted  colors;  nevertheless  he  undertakes  the 
whole  duty  of  incubation.  § 

*The  natives  of  Ceram  (Wallace,  "Malay  Archipelago,"  vol.  ii. 
p.  150)  assert  that  the  male  and  female  sit  alternately  on  the  eggs; 
but  this  assertion,  as  Mr.  Bartlett  thinks,  may  be  accounted  for  by 
the  female  visiting  the  nest  to  lay  her  eggs. 

+  "  The  Student,"  April,  1870,  p.  124. 

X  See  the  excellent  account  of  the  habits  of  this  bird  under  con- 
finement, by  Mr.  A.  W.  Bennett,  in  "  Land  and  Water,"  May,  1868, 
p.  233. 

§Mr.  Sclater,  on  the  incubation  of  the  Struthiones,  "  Proc.  Zool. 
Soc,"  JuneO,  1863.  So  it  is  with  the  Rhea  daricinii:  Capt.  Mus- 
ters says  ("At  Home  with  the  Patagonians,"  1871,  p.  128),  that  the 
male  is  larger,  stronger  and  swifter  than  the  female,  and  of  slightly 
darker  colors;  yet  he  takes  sole  charge  of  the  eggs  and  of  the  young, 
just  as  does  the  male  of  the  common  species  of  Rhea. 


546  THE  DESCENT  OF  MAN. 

I  will  specify  the  few  other  cases  known  to  me,  in  which 
the  female  is  more  conspicuously  colored  than  the  male, 
althougli  nothing  is  known  about  the  manner  of  incuba- 
tion. With  the  carrion-hawk  of  the  Falkland  Islands 
[Milvago  leucurus)  I  was  much  surprised  to  find  by  dissec- 
tion that  the  individuals,  which  had  all  their  tints  strongly 
pronounced,  with  the  cere  and  legs  orange-colored,  were  the 
adult  females;  Avhile  those  with  duller  plumage  and  gray 
legs  were  the  males  or  tlie  young.  In  an  Australian  tree- 
creeper  [Climacteris  erythrops)  the  female  differs  from  the 
male  in  "being  adorned  with  beautiful,  radiated,  rufous 
markings  on  the  tliroat,  the  male  having  this  part  quite 
plain."  Lastly,  in  an  Australian  night-jar  "the  female 
always  exceeds  the  male  in  size  and  in  the  brilliance  of 
her  tints;  the  males,  on  the  otljer  hand,  have  two  white 
spots  on  the  primaries  more  conspicuous  than  in  the 
female."* 

We  thus  see  that  the  cases  in  which  female  birds  are 
more  conspicuously  colored  than  the  males,  with  the  young 
in  their  immature  plumage  resembling  the  adult  males 
instead  of  the  adult  females,  as  in  the  previous  class,  are 
not  numerous,  though  they  are  distributed  in  various 
orders.  The  amount  of  difference,  also,  between  the  sexes 
is  incomparably  less  than  that  wliich  frequently  occurs  in 
the  last  class;  so  that  the  cause  of  the  difference,  whatever 
it  may  have  been,  has  here  acted  on  the  females  either  less 
energetically  or  less  persistently  than  on  the  males  in  the 
last  class.     Mr.  Wallace  believes  that  the  males  have  had 

*  For  the  Milvago,  see  "Zoology  of  the  Voyage  of  the  'Beagie': 
Birds,"  1841,  p.  16.  For  the  Climacteris  and  night-jar  (Eurostopo- 
dus),  see  Gould's  "  Hand-book  to  the  Birds  of  Australia,"  vol.  i,  pp. 
602,  97.  The  New  Zealand  shieldrake  {Tadorna  variegata)  offers  a 
quite  anomalous  case;  the  head  of  the  female  is  pure  white,  and  her 
back  is  redder  than  that  of  the  male;  the  head  of  tflie  male  is  of  a 
rich  dark  bronzed  color,  and  his  back  is  clothed  with  finely  penciled 
slate-colored  feathers,  so  that  altogether  he  may  be  considered  as  the 
more  beautiful  of  the  two.  He  is  larger  and  more  pugnacious  than 
the  female,  and  does  not  sit  on  the  eggs.  So  that  in  all  these  respects 
this  species  comes  under  our  first  class  of  cases;  but  Mr.  Sclater 
("Proc.  Zool.  Soc,"  1866,  p.  150)  was  much  surprised  to  observe 
that  the  young  of  both  sexes,  when  about  three  months  old,  resem- 
bled in  their  dark  heads  and  necks  the  adult  males,  instead  of  the 
adult  females;  so  that  it  would  appear  in  this  case  that  the  females 
have  been  modified,  while  the  males  and  the  young  have  retained  9, 
former  state  of  plumage. 


BIRDS.  547 

their  colors  rendered  less  conspicuous  for  the  sake  of  pro- 
tection during  the  period  of  incubation;  but  the  difference 
between  the  sexes  in  hardly  any  of  the  foregoing  cases 
appears  sufficiently  great  for  this  view  to  be  safely  accepted. 
In  some  of  the  cases  the  brighter  tints  of  the  female  are 
almost  confined  to  the  lower  surface,  and  the  males,  if  thus 
colored,  would  not  have  been  exposed  to  danger  while 
sitting  on  the  eggs.  It  should  also  be  borne  in  mind  that 
the  males  are  not  only  in  a  slight  degree  less  conspicuously 
colored  than  the  females,  but  are  smaller  and  weaker. 
They  have,  moreover,  not  only  acquired  the  maternal 
instinct  of  incubation,  but  are  less  pugnacious  and 
vociferous  than  the  females,  and  in  one  instance  have 
simpler  vocal  organs.  Thus,  an  almost  complete  transposi- 
tion of  the  instincts,  habits,  disposition,  color,  size,  and  of 
some  points  of  structure,  has  been  effected  between  the  two 
sexes. 

Now,  if  we  might  assume  that  the  males  in  the  present 
class  have  lost  some  of  that  ardor  which  is  usual  to  their 
sex,  so  that  they  no  longer  search  eagerly  for  the  females; 
or,  if  we  might  assume  that  the  females  have  become  much 
more  numerous  than  the  males — and  in  the  case  of  one 
Indian  Turnix  the  females  are  said  to  be  ^^  much  more 
commonly  met  with  than  the  males "  * — then  it  is  not 
improbable  that  the  females  would  have  been  led  to  court 
the  males,  instead  of  being  courted  by  them.  This  indeed 
is  the  case  to  a  certain  extent  with  some  birds,  as  we  have 
seen  with  the  peahen,  wild  turkey,  and  certain  kinds  of 
grouse.  Taking  as  our  guide  the  habits  of  most  male 
birds,  the  greater  size  and  strength,  as  well  as  the  extraor- 
dinary pugnacity  of  the  females  of  the  Turnix  and  emu, 
must  mean  that  they  endeavor  to  drive  away  rival  females 
in  order  to  gain  possession  of  the  male;  and  on  this  view 
all  the  facts  become  clear  ;  for  the  males  would  probably 
be  most  charmed  or  excited  by  the  females  which  were  the 
most  attractive  to  them  by  their  bright  colors,  other  orna- 
ments, or  vocal  powers.  Sexual  selection  would  then  do 
its  work,  steadily  adding  to  the  attractions  of  the  females  •, 
the  males  and  the  young  being  left  not  at  all,  or  but  little, 
modified. 

Class  III.      When  the  adult  male  resembles  the  adult 

*  Jerdon,  "BiKis  of  India,"  vol.  iii,  p.  599. 


548  THE  DESCENT  OF  MAN. 

female,  tlie  young  of  both  sexes  have  a  peimliar first  phimage 
of  their  own. — In  this  class  the  sexes  when  adult  resemble 
each  other  and  differ  from  the  young.  This  occurs  with 
many  birds  of  many  kinds.  The  male  robin  can  hardly  be 
distinguished  from  the  female,  but  the  young  are  widely 
different,  with  their  mottled  dusky-olive  and  brown  plum- 
age. The  male  and  female  of  the  splendid  scarlet 
ibis  are  alike,  wliile  the  young  are  brown;  and  the  scarlet 
color,  though  common  to  both  sexes,  is  apparently  a  sexual 
character,  for  it  is  not  well  developed  in  either  sex  nnder 
confinement ;  and  a  loss  of  color  often  occurs  with  brill- 
iant males  when  they  are  confined.  With  many  species  of 
herons  the  young  differ  greatly  from  the  adults;  and  the 
summer  plumage  of  the  latter,  though  common  to  both 
sexes,  clearly  has  a  nuptial  character.  Young  swans  are 
slate-colored,  while  the  mature  birds  are  pure  white;  but  it 
would  be  superfluous  to  give  additional  instances.  These 
differences  between  the  young  and  the  old  apparently 
depend,  as  in  the  last  two  classes,  on  the  young  having 
retained  a  former  or  ancient  state  of  plumage,  while  the  old 
of  both  sexes  have  acquired  a  new  one.  When  the  adults 
are  bright  colored,  we  may  conclude  from  the  remarks  just 
made  in  relation  to  the  scarlet  ibis  and  to  many  herons,  and 
from  the  analogy  of  the  species  in  the  first  class,  that  such 
colors  have  been  acquired  through  sexual  selection  by  the 
nearly  mature  males ;  but  that,  differently  from  what 
occurs  in  the  first  two  classes,  the  transmission,  though  lim- 
ited to  the  same  age,  has  not  been  limited  to  the  same  sex. 
Consequently,  the  sexes  when  mature  resemble  each  other 
and  differ  from  the  young. 

Class  IV.  When  the  adult  male  resembles  the  adult 
female,  the  young  of  both  sexes  in  their  first  plumage  resem- 
ble the  adults. — In  this  class  the  young  and  the  adults  of 
both  sexes,  whether  TDrilliantly  or  obscurely  colored,  resem- 
ble each  other.  Such  cases  are,  I  think:,  more  common 
than  those  in  the  last  class.  We  have  in  England  instances 
in  the  kingfisher,  some  woodpeckers,  the  jay,  magpie, 
crow,  and  many  small  dull-colored  birds,  such  as  the 
hedge-warbler  or  kitty-wren.  But  the  similarity  in  plum- 
age between  the  young  and  the  old  is  never  complete,  and 
graduates  away  into  dissimilarity.  Thus  the  young  of 
some  members  of  the  kingfisher  family  are  not  only  les§ 


BIRDS.  549 

vividly  colored  than  the  adults,  hut  many  of  the  feathers 
on  the  lower  surface  are  edged  with  brown* — a  vestige 
probably  of  a  former  state  of  the  plumage.  Frequently  in 
the  same  group  of  birds,  even  within  the  same  genus 
for  instance,  in  the  Australian  genus  of  paroquets 
(Platycercus),  the  young  of  some  species  closely  resemble, 
while  the  young  of  other  species  differ  consider- 
ably from,  their  parents  of  both  sexes,  which  are  alike,  f 
Both  sexes  and  the  young  of  the  common  jay  are  closely 
similar;  but  in  the  Canada  jay  {Perisoreus  canadensis)  the 
young  differ  so  much  from  their  parents  that  they  were 
formerly  described  as  distinct  species.  J; 

I  may  remark  before  proceeding  that,  under  the  present 
and  next  two  classes  of  cases,  the  facts  are  so  complex  and 
the  conclusions  so  doubtful  that  any  one  who  feels  no 
especial  interest  in  the  subject  had  better  pass  them  over. 


The  brilliant  or  conspicuous  colors  whicli  characterize  many  birds 
in  the  present  class  can  rarely  or  never  be  of  service  to  them  as  a 
protection;  so  that  they  have  probably  been  gained  by  the  males 
through  sexual  selection  and  then  transferred  to  the  females  and 
the  young.  It  is,  however,  possible  that  the  males  may  have  selected 
the  more  attractive  females;  and  if  these  transmitted  their  chaiacters 
to  their  offspring  of  both  sexes  the  same  results  would  follow  as 
from  the  selection  of  the  more  attractive  males  by  the  females.  But 
there  is  evidence  that  this  contingency  has  rarely,  if  ever,  occurred 
in  any  of  those  groups  of  birds  in  which  the  sexes  are  generally 
alike;  for,  if  even  a  few  of  the  succe.ssive  variations  had  failed  to  be 
transmitted  to  both  sexes,  the  females  would  have  slightly  exceeded 
the  males  in  beauty.  Exactly  the  reverse  occurs  under  nature;  for, 
in  almost  every  large  group  in  which  the  sexes  generally  resemble 
each  other,  the  males  of  some  few  species  are  in  a  slight  degree  more 
brightly  colored  than  the  females.  It  is  again  possible  that  the 
females  may  have  selected  the  more  beautiful  males,  these  males 
having  reciprocally  selected  the  more  beautiful  females;  but  it  is 
doubtful  whether  this  double  process  of  selection  would  be  likely  to 
occur,  owing  to  the  greater  eagerness  of  one  sex  than  the  other,  and 
whether  it  would  be  more  efficient  than  selection  on  one  side  alone. 
It  is,  therefore,  the  most  probable  view  that  sexual  selection  has 
acted,  in  the  present  class,  as  far  as  ornamental  characters  are  con- 
cerned, in  accordance  with  the  general  rule  throughout  the  animal 
kingdom,  that  is,  on  the  males;  and  that  these  have  transmitted  their 

♦Jerdon,  "Birds  of  India,"  vol.  i,  pp.  222,  228.     Gould's  ♦'Hand- 
book to  the  Birds  of  Australia,"  vol.  i,  pp.  124,  130. 
f  Gould,  ibid,  vol.  ii,  pp.  37,  46,  56. 
^Audubon,  "  Omith.  Biography,"  vol.  ii,  p.  55. 


550  THE  DESCENT  OF  MAN. 

gradually  acquired  colors,  either  equally  or  almost  equally,  to  their 
offspring  of  both  sexes. 

Another  point  is  more  doubtful,  namely,  whether  the  successive 
variations  first  appeared  in  the  males  after  they  had  become  nearly 
mature  or  while  quite  young.  In  either  case  sexual  selection  must 
have  acted  on  the  male  when  he  had  to  compete  with  rivals  for  the 
possession  of  the  female;  and  in  both  cases  the  characters  thus 
acquired  have  been  transmitted  to  both  sexes  and  all  ages.  But 
these  characters,  if  acquired  by  the  males  when  adult,  may  have  been 
transmitted  at  first  to  the  adults  alone,  and  at  some  subsequent  period 
transferred  to  the  young.  For  it  is  known  that  when  the  law  of 
inheritance  at  corresponding  ages  fails  the  offspring  often  inherit 
characters  at  an  earlier  age  than  that  at  which  they  first  appeared 
in  their  parents.*  Cases  apparently  of  this  kind  have  been  observed 
with  birds  in  a  state  of  nature.  For  instance,  Mr.  Blyth  has  seen 
specimens  of  Lanius  rufus  and  of  Golymbus  glacialis  which  had 
assumed  while  young,  in  a  quite  anomalous  manner,  the  adult 
plumage  of  their  parents,  f  Again,  the  young  of  the  common  swan 
(Cygnus  olor)  do  not  cast  off  their  dark  feathers  and  become  white 
until  eighteen  months  or  two  years  old;  but  Dr.  F.  Forel  has 
described  the  case  of  three  vigorous  young  birds,  out  of  a  brood  of 
four,  which  were  born  pure  white.  These  young  birds  were  not 
albinos,  as  shown  by  the  color  of  their  beaks  and  legs,  which  nearly 
resembled  the  same  parts  in  the  adults. :{: 

It  may  be  worth  while  to  illustrate  the  above  three  modes  by 
which,  in  the  present  class,  the  two  sexes  and  the  young  may  have 
come  to  resemble  each  other,  by  the  curious  case  of  the  genus 
Passer. §  In  the  house-sparrow  (P.  domesticus)  the  male  differs 
much  from  the  female  and  from  the  young.  The  young  and  the 
females  are  alike,  and  resemble  to  a  large  extent  both  sexes  and  the 
young  of  the  sparrow  of  Palestine  {P.  hrdchydactyhis),  as  well  as  of 
some  allied  species.  We  may  therefore  assume  that  the  female  and 
young  of  the  house-sparrow  approximately  show  us  the  plumage  of 
the  progenitor  of  the  genus.  Now  with  the  tree-sparrow  {P.  mon- 
ianus)  both  sexes  and  the  young  closely  resemble  the  male  of  the 
house-sparrow;  so  that  they  have  all  been  modified  in  the  same 
manner,  and  all  depart  from  the  typical  coloring  of  their  early  pro- 
genitors. This  may  have  been  effected  by  a  male  ancestor  of  the  tree- 
sparrow  having  varied,  firstly,  when  nearly  mature;  or,  secondly, 
while  quite  young,  and  by  having  in  either  case  transmitted  his 
modified  plumage  to  the  females  and  the  young;  or,  thirdly,  he  may 
have  varied  when  adult  and  transmitted  his  plumage  to  both  adult 
sexes,  and,  owing  to  the  failure  of  the  law  of  inheritance  at  corre- 
sponding ages,  at  some  subsequent  period  to  his  young. 

It  is  impossible  to  decide  which  of  these  three  modes  has  generally 

*  "  Variation  of  Animals  and  Plants  under  Domestication,"  vol.  11,  p.  79. 

t  Charlesworth's  "  Maj?.  of  Nat.  Hist.,"  vol.  i,  1837,  pp.  30.5,  306. 

t "  Bulletin  de  la  Soc.  Vaudoise  des  Sc.  Nat.,"  vol.  x,  1869,  p.  132.  The 
young  of  the  Polish  swan,  Cygnvs  immvtafjUit^  of  Yarrell,  are  always  white; 
out  this  species,  as  Mr.  Sclater  informs  me,  is  believed  to  be  nothing  more  than 
a  variety  of  the  domestic  swan  {Cygnvs  olar). 

§  I  am  indebted  to  Mr.  Blyth  for  in  formation  in  regard  to  this  genus.  The 
sparrow  of  Palestine  belongs  to  the  sub-genus  Petronia. 


BIRDS.  551 

prevailed  tlirotighout  the  present  class  of  cases.  That  the  males 
varied  while  young  and  transmitted  their  variations  to  their  offspring' 
of  both  sexes  is  the  most  probable.  I  may  here  add  that  1  have, 
with  little  success,  endeavored,  by  consulting  various  works,  to 
decide  how  far  the  period  of  variation  in  birds  has  generally  deter- 
mined the  transmission  of  characters  to  one  sex  or  to  both.  The  two 
rules,  often  referred  to  (namely,  that  variations  occurring  late  in  life 
are  transmitted  to  one  and  the  same  sex,  while  those  which  occur 
earlj'  in  life  are  transmitted  to  both  sexes),  apparently  hold  good  in 
the  first,*  second,  and  fourth  cla.sses  of  cases;  but  they  fail  in  the 
third,  often  in  the  fifth, f  and  in  the  sixth  small  class.  They  apply, 
however,  as  far  as  I  can  judge,  to  a  considerable  majority  of  the 
species;  and  we  mast  not  forget  the  striking  generalization  by  Dr. 
W.  Marshall  with  respect  to  the  protuberances  on  the  heads  of 
birds.  Whether  or  not  the  two  rules  generally  hold  good,  we  may 
conclude  from  the  facts  given  in  the  eighth  chapter  that  the  period 
of  variation  is  one  important  element  in  determining  the  form  of 
transmission. 

With  birds  it  is  difficult  to  decide  by  what  standard  we  ought  to 
judge  of  the  earliness  or  lateness  of  the  period  of  variation,  whether 
by  the  age  in  reference  to  the  duration  of  life,  or  to  the  power  of 
reproduction,  or  to  the  number  of  moults  through  which  the  species 
passes.  The  moulting  of  birds,  even  within  the  same  family,  some- 
times differs  much  without  any  assignable  cause.  Some  birds  moult 
so  early  that  nearly  all  the  body-feathers  are  cast  off  before  the  first 
wing- feathers  are  fully  grown;  and  we  cannot  believe  that  this  was 
the  primordial  state  of  things,  \^'hen  the  period  of  moulting  has 
been  accelerated  the  age  at  which  the  colors  of  the  adult  plumage 
are  first  developed  will  falsely  appear  to  us  to  be  earlier  than  it 
really  is.  This  may  be  illustrated  by  the  practice  followed  by  some 
bird-fanciers,  who  pull  out  a  few  feathers  from  the  breast  of  nestling 
bullfinches,  and  from  the  head  or  neck  of  young  Gold  pheasants,  in 
order  to  ascertain  their  sex;  for  in  the  males,  these  feathers  are 
immediately  replaced  by  colored  ones.:j:  The  actual  duration  of  life 
is  known  in  but  few  birds,  so  that  we  can  hardly  judge  by  this 
standard.  And  with  reference  to  the  period  at  which  the  power  of 
reproduction  is  gained,  it  is  a  remarkable  fact  that  various  birds 
occasionally  breed  while  retaining  their  immature  plumage.§ 

*  For  instance,  the  males  of  Tanagra  (estiva  and  FrivgiUa  cyanea  require 
three  years,  the  male  of  Fritigilla  citis  four  vears,  to  complete  their  beautful 
plumage,  (See  Audubon,  "  Ornith.  Biography,"  vol.  i,  pp.  233,  280,  378).  The 
llarlequin  duck  takes  three  years  (ibid,  vol.  iii,  p.  614).  The  male  of  the  Gold 
pheasant,  as  I  hear  from  Mr.  Jenner  Weir,  can  be  distinguished  from  the 
female  when  about  three  months  old,  but  he  does  not  acquire  his  full  splendor 
until  the  end  of  September  in  the  following  year. 

tThus  the  Ibis  tantalus  and  Grn/s  amencanus  take  four  years,  the  Flamingo 
several  years,  and  the  Ardea  hidovicaiia  two  years,  before  they  acquire  their 
perfect  plumage.    See  Audubon,  ibid,  vol.  i,  p.  221;  vol.  iii,  pp.  133,  Via.  211. 

t  Mr.  Blyth,  in  Charlesworth's  "  Mag.  of  Nat.  Hist.,"  vol.  i,  1837,  p.  300. 
Mr.  Bartlett  has  informed  me  in  regard  to  Gold  pheasants. 

S I  have  noticed  the  following  cases  in  Audubon's  "  Ornith.  Biography:" 
The  redstart  of  America  (Mi/scapica  ii/ficil/d},  vol.  i.  p.  203.  The  Ibis  tantalus 
takes  four  years  to  come  to  full  maturity,  but  sometimes  breeds  in  the  second 
year  (vol.  iii,  p.  133).  The  Gi'us  amencatnis  takes  the  same  time,  but  breeds  be- 
fore acquiring  its  full  plumage  (vol.  iii,  p.  211).    The  Adnlts  of  Ardea  coendea 


552  THE  DESCENT  OF  MAN. 

The  fact  of  birds  breeding  in  their  immature  plumage  seems 
opposed  to  the  belief  that  sexual  selection  has  played  as  important  a 
part,  as  I  believe  it  has,  in  giving  ornamental  colors,  plumes,  etc.,  to 
the  males,  and,  by  means  of  equal  transmission,  to  the  females  of 
many  species.  The  objection  would  be  a  valid  one,  if  the  younger 
and  less  ornamented  males  were  as  successful  in  winning  females  and 
propagating  their  kind,  as  the  older  and  more  beautiful  males.  But 
we  have  no  reason  to  suppose  that  this  is  the  case.  Audubon 
speaks  of  the  breeding  of  the  immature  males  of  IMh  tantalus  as  a 
rare  event,  as  does  Mr.  Swinhoe,  in  regard  to  the  immature  males  of 
Oriolus.*  If  the  young  of  any  species  in  their  immature  plumage 
were  more  successful  in  winning  partners  than  the  adults,  the  aduit 
plumage  would  probably  soon  be  lost,  as  the  males  would  prevail 
which  retained  their  immature  dress  for  the  longest  period,  and  thus 
the  character  of  the  species  would  ultimately  be  modified.-}  If,  on 
the  other  hand,  the  young  never  succeeded  in  obtaining  a  female, 
the  habit  of  early  reproduction  would  perhaps  be  sooner  or  later 
eliminated,  from  being  superfluous  and  entailing  waste  of  power. 

The  plumage  of  certain  birds  goes  on  increasing  in  beauty  during 
many  years  after  they  are  fully  mature;  this  is  the  case  with  the 
train  of  the  peacock,  with  some  of  the  birds  of  paradise,  and  with 
the  crests  and  plumes  of  certain  herons,  for  instance,  the  Ardea 
hidovicana.X  But  it  is  doubtful  whether  the  continued  development 
of  such  feathers  is  the  result  of  the  selection  of  successive  beneficial 
variations  (though  this  is  the  most  probable  view  with  birds  of  para- 
dise) or  merely  of  continuous  growth.  Most  fishes  continue  increas- 
ing in  size,  as  long  as  they  are  in  good  health  and  have  plenty  of 
food;  and  a  somewhat  similar  law  may  prevail  with  the  plumes  of 
birds. 

CiiASS  V.  WTien  the  adults  of  both  sexes  h^ve  a  distinct  winter 
and  summer  'plumage,  whether  or  not  the  male  differs  from  the 
female,  the  young  resenMe  the  adults  of  both  sexes  in  their  tcinter 
dress,  or  much  more  rarely  in  their  mimmer  dress,  or  they  resemble 

are  blue  and  the  youn?  white;  and  white,  mottled,  and  mature  blue  birds 
may  all  be  seen  breeding  together  (vol.  iv,  p.  58);  but  Mr.  Blyth  informs  me 
that  certain  herons  apparently  are  dimorphic,  for  white  and  colored  individ- 
uals of  the  same  age  may  be  observed.  The  Harlequin  duck  (Anas  hhttnonica, 
Linn.)  takes  three  years  to  acquire  its  full  plumage,  though  many  birds  breed 
in  the  second  year  (vol.  ill,  p.  614).  The  white-headed  eagle  (Falco  leucocej^halxis), 
vol.  iii,  p.  210,  is  likewise  known  to  breed  in  its  immature  state.  Some  species 
of  Oriolus  (according  to  Mr.  Blyth  and  Mr.  Swinhoe,  in  "  Ibis,"  July,  1863,  p. 
68)  likewise  breed  before  they  attain  their  full  plumage. 

*  See  the  last  foot-note. 

t  Other  animals,  belonging  to  quite  distinct  classes,  are  either  habitually 
or  occasionally  capable  of  breeding  before  they  have  fully  acquired  their 
adult  characters.  This  is  the  case  with  the  young  males  of  the  salmon. 
Several  amphibians  have  been  known  to  breed  while  retaining  their  larval 
structure.  Fritz  Muller  has  shown  ("  Facts  and  Arguments  for  Darwin," 
Eng.  trans.,  1869,  p.  79)  that  the  males  of  several  amphipod  crustaceans  become 
sexually  mature  while  young;  and  I  infer  that  this  is  a  case  of  premature 
breeding,  because  they  have  not  as  yet  acquired  their  fully  developed  claspers. 
All  such  facts  are  highly  interesting,  as  bearing  on  one  means  by  which  species 
may  undergo  great  modifications  of  character. 

X  Jerdon,  "  Birds  of  India,"  vol.  iii,  p.  507,  on  the  peacock.  Dr.  Marshall 
thinks  that  the  older  and  more  brilliant  males  of  birds  of  paradise  have  an 
advantage  over  the  younger  males;  see  "Archives  Neerlandaises,"  torn,  vi, 
1871.    On  Ardea,  Audubon,  ibid,  vol.  iii,  p.  139. 


BIRDS.  553 

tJie  females  alone.  Or  the  young  may  have  an  intermediate 
character;  or,  again,  they  may  differ  greatly  from  tJie  adults  in 
both  their  seasonal  plumages. — The  cases  in  this  class  are  singularly- 
complex;  nor  is  this  surprising,  as  they  depend  on  inheritance, 
limited  in  a  greater  or  less  degree  in  three  different  ways,  namely, 
by  sex,  age,  and  the  season  of  the  year.  In  some  cases  the 
individuals  of  the  same  species  pass  through  at  least  five  distinct 
states  of  plumage.  With  the  species  in  which  the  male  differs 
from  the  female  during  the  summer  season  alone,  or,  which  is  rarer, 
during  both  seasons,*  the  young  generally  resemble  the  females — 
as  with  the  so-called  goldfinch  of  North  America,  and  apparently 
with  the  splendid  Maluri  of  x\ustralia.f  With  those  species,  the 
sexes  of  which  are  alike  during  both  the  summer  and  winter,  the 
young  may  resemble  the  adults,  firstly,  in  their  winter  dress  ;  sec- 
ondly, and  this  is  of  much  rarer  occurrence,  in  their  summer  dress  ; 
thirdly,  they  may  be  intermediate  between  these  two  states ;  and, 
fourthly,  they  may  differ  greatly  from  the. adults  at  all  seasons.  We 
have  an  instance  of  the  first  of  these  four  cases  in  one  of  the  egrets 
of  India  {Buphus  coromandus),  in  which  the  young  and  the  adults  of 
both  sexes  are  white  during  the  winter,  the  adults  becoming  golden- 
buff  during  the  summer.  With  the  gaper  {Anastomus  oscitans)  of 
India  we  have  a  similar  case,  but  the  colors  are  reversed ;  for  the 
young  and  the  adults  of  both  sexes  are  gray  and  black  during  the 
winter,  the  adults  becoming  white  during  the  summer. :{  As  an 
instance  of  the  second  case,  the  young  of  the  razor-bill  {Alca  torda, 
Linn.),  in  an  early  state  of  plumage,  are  colored  like  the  adults  dur- 
ing the  summer;  and  the  young  of  the  white-crowned  sparrow  of 
North  America  (Fnngilla  leu<^ophrys\  as  soon  as  fledged,  have  elegant 
white  stripes  on  their  heads,  which  are  lost  by  the  young  and  the  old 
during  the  winter.  §  With  respect  to  the  third  case,  namely,  that  of 
the  young  having  an  intermediate  character  between  the  summer 
and  winter  adult  plumages,  Tarrell  ||  insists  that  this  occurs  with 
many  waders.  Lastly,  in  regard  to  the  young  differing  greatly  from 
both  sexes  in  tlieir  adult  summer  and  winter  plumages,  this  occurs 
with  some  hei  5ns  and  egrets  of  North  America  and  India — the 
young  alone  being  white. 

I  will  make  only  a  few  remarks  on  these  complicated  cases.  When 
the  young  resemble  the  females  in  their  summer  dress,  or  the  adults 
of  both  sexes  in  their  winter  dress,  the  cases  differ  from  those  given 
under  Classes   I  and  III  only  in  the   characters  originally  acquired 

*For  illustrative  cases  see  vol.  iv,  of  Macgillivray's  "  Hist.  Brit.  Birds;" 
on  Tringa,  etc.,  pp.  229,  271;  on  the  Machetes,  p.  172;  on  the  Charadrim  hiati- 
cuia,  p.  118;  on  the  Charadtius  pluviaiis,  p.  94. 

t  For  the  goldfinch  of  North  America,  FringtUa  frisfis,  Linn.,  see  Audubon, 
"  Ornith.  Biography,"  vol.  i,  p.  172.  For  the  Maliu-i,  Gould's  *'  Hand-book  to 
the  Birds  of  Australia,"  vol.  i,  p.  318. 

1 1  am  indebted  to  Mr.  Blyth  for  information  as  to  the  Buphus;  see  also 
Jerdon,  "  Birds  of  India,"  vol.  iii,  p.  749.  On  the  Anastomus,  see  Blyth,  in 
"  Ibis,"  1867  p.  173. 

§  On  the  Alca,  see  Macgillivray,  "  Hist.  Brit.  Birds,"  vol.  v,  p,  347.  On  the 
FringUla  lencophryg,  Audubon,  ibid,  vol.  ii,  p.  89.  I  shall  have  hereafter  to 
refer  to  the  young  of  certain  herons  and  egi-ets  being  white. 

I  History  of  British  Birds,"  vol.  1, 1839,  p.  159. 


554  THE  DESCENT  OF  MAN, 

by  the  males  during  the  breeding-season  liaving  been  limited  in  theii 
transmission  to  the  corresponding  season.  When  the  adults  have  a 
distinct  summer  and  winter  plumage,  an  I  the  young  differ  from  both, 
the  case  is  more  difficult  to  understand.  We  may  admit  as  probable 
that  the  young  have  retained  an  ancient  state  of  plumage;  we  can 
account  by  sexual  selection  for  the  summer  or  nuptial  plumage  of  the 
adults,  but  how  are  we  to  account  for  their  distinct  winter  plumage  ? 
If  we  could  admit  that  this  plumage  serves  in  all  cases  as  a  protec- 
tion, its  acquirement  would  be  a  simple  affair;  but  there  seems  no 
good  reason  for  this  admission.  It  may  be  suggested  that  the 
widely  different  conditions  of  life  during  the  winter  and  summer 
have  acted  in  a  direct  manner  on  the  plumage  ;  this  may  have  had 
some  effect,  but  I  have  not  much  confidence  in  so  great  a  difference 
as  we  sometimes  see  between  the  two  plumages  having  been  thus 
caused.  A  more  probable  explanation  is,  that  an  ancient  style  of 
plumage,  partially  modified  through  the  transference  of  some  char- 
acters from  the  summer  plumage,  has  been  retained  by  the  adults 
during  the  winter.  Finally,  all  the  cases  in  our  present  class  appa- 
rently depend  on  characters  acquired  by  the  adult  males  having 
been  variously  limited  in  their  transmission  according  to  age,  season, 
and  sex;  but  it  would  not  be  worth  while  to  attempt  to  follow  out 
these  complex  relations. 

Class  VI.  The  young  in  their  first  plumage  differ  from  each  other 
according  to  sex;  the  young  males  resembling  more  or  less  closely  the 
adult  males,  and  the  young  females  more  or  less  closely  the  adult 
females. — The  cases  in  the  present  class,  though  occurring  in  various 
groups,  are  not  numerous;  yet  it  seems  the  most  natural  thing  that 
the  young  should  at  first  somewhat  resemble  the  adults  of  the  same 
sex,  and  gradually  become  more  and  more  like  them.  The  adult 
male  blackcap  (Sylvia  atricapilla)  has  a  black  head,  that  of  the 
female  being  reddish-brown;  and  1  am  informed  by  Mr.  Blyth,  that 
the  young  of  both  sexes  can  be  distinguished  by  this  character  even 
as  nestlings.  In  the  family  of  thrushes  an  unusual  number  of  simi- 
lar cases  have  been  noticed ;  thus,  the  male  blackbird  {Turdus 
merula)  can  be  distinguished  in  the  nest  from  the  female.  The  two 
sexes  of  the  vaock-mg-hivdi  {Turdus  poly glottus,  liinn.)  differ  very  little 
from  each  other,  yet  the  males  can  easily  be  distinguished  at  a  very 
early  age  from  the  females  by  showing  more  pure  white.*  The 
males  of  a  forest-thrush  and  of  a  rock-thrush  {Orocetes  erythrogastra 
and  Petrocincla  cyanea)  have  much  of  their  plumage  of  a  fine  blue, 
while  the  females  are  brown;  and  the  nestling  males  of  both  species 
have  their  main  wing  and  tail  feathers  edged  with  blue,  while  those 
of  the  female  are  edged  with  brown,  f  In  the  young  blackbird  the 
wing-feathers  assume  their  mature  character  and  become  black  after 
the  others;  on  the  other  hand,  in  the  two  species  just  named  the 
wing- feathers  become  blue  before  the  others.  The  most  probable 
view  with  reference  to  the  cases  in  the  present  class  is  that  the  males, 

♦  Audubon  "  Ornith.  Biography,"  vol.  1,  p.  113. 

tMr.  C.  A.  Wright,  in  "Ibis,"  vol.  vi,  1864,  p.  65.  Jerdon,  "Birds  of 
India,"  vol.  i,  p.  515.  See  also  on  the  blackbird,  Bljrth,  in  Charlesworth's 
"  Mag.  of  Nat.  History,"  vol.  i,  1837,  p.  113. 


J^TRDS.  566 

differently  from  wtat  occurs  in  Class  I,  Lave  transmitted  their  colors 
to  their  male  offspring  at  an  earlier  age  than  that  at  which  they  were 
first  acquired;  for,  if  the  males  had  varied  while  quite  young,  their 
characters  would  probably  have  been  transmitted  to  both  sexes.* 

In  Aithurus  polytmus,  a  humming-bird,  the  male  is  splendidly 
colored  black  and  green,  and  two  of  the  tail-feathers  are  immensely 
lengthened;  the  female  has  an  ordinary  tail  and  inconspicuous 
colors;  now  the  young  males,  instead  of  resembling  the  adult 
female,  in  accordance  with  the  common  rule,  begin  from  the  first  to 
assume  the  colors  proper  to  their  sex,  and  their  tail-feathers  soon 
become  elongated.  I  owe  this  information  to  Mr.  Gould,  who  has 
given  me  the  following  more  striking  and  as  yet  unpublished  case. 
Two  humming-birds  belonging  to  the  genus  Eustephanus,  both 
beautifully  colored,  inhabit  the  small  island  of  Juan  Fernandez,  and 
have  always  been  ranked  as  specifically  distinct.  But  it  has  lately 
been  ascertained  that  the  one  which  is  of  a  rich  chestnut-brown 
color  with  a  golden-red  head,  is  the  male,  while  the  other,  which  is 
elegantly  variegated  with  green  and  white,  with  a  metallic  green 
head,  is  the  female.  Now  the  young  from  the  first  somewhat  resem- 
ble the  adults  of  the  corresponding  sex,  the  resemblance  gradually 
becoming  more  and  more  complete. 

In  considering  this  last  case,  if  as  before  we  take  the  plumage  of 
the  young  as  our  guide,  it  would  appear  that  both  sexes  have  been 
rendered  beautiful  independently;  and  not  that  one  sex  has  partially 
transferred  its  beauty  to  the  other.  The  male  apparently  has 
acquired  his  bright  colors  through  sexual  selection  in  the  same 
manner  as,  for  instance,  the  peacock  or  pheasant  in  our  first  class  of 
cases;  and  the  female  in  the  same  manner  as  the  female  Rhynchaea 
or  Turnix  in  our  second  class  of  cases.  But  there  is  much  difficulty 
in  understanding  how  this  could  have  been  effected  at  the  same  time 
with  the  two  sexes  of  the  same  species.  Mr.  Salvin  states,  as  we 
have  seen  in  the  eighth  chapter,  that  with  certain  humming-birds 
the  males  greatly  exceed  the  females  in  number,  while  with  other 
species  inhabiting  the  same  country  the  females  greatly  exceed  the 
males.  If,  then,  we  might  assume  that  during  some  former  length- 
ened period  the  males  of  the  Juan  Fernandez  species  had  greatly 
exceeded  the  females  in  number,  but  that  during  another  lengthened 
period  the  females  had  far  exceeded  the  males,  we  could  understand 
how  the  males  at  one  time,  and  the  females  at  another,  might  have 
been  rendered  beautiful  by  the  selection  of  the  brighter-colored 
individuals  of  either  sex;  both  sexes  transmitting  their  characters  to 
their  young  at  a  rather  earlier  age  than  usual.  Whether  this  is  the 
true  explanation  I  will  not  pretend  to  say ;  but  the  case  is  too  remark- 
able to  be  passed  over  without  notice. 


♦The  following  additional  cases  may  be  mentioned:  the  young  males  of 

females   (Audubon, 
nestlings  of  a  blue 

.  ,    .  of  India,"  vol.  i,  p. 

389).  Mr.  Blyth  also  informs  me  that  the  sexes  of  the  stonechat,  <Saxicota  itibi- 
cola,  are  distmguishable  at  a  very  early  age.  Mr.  Salvin  giv<^s  ("  Proc.  Zoolog. 
Soc.,"  1870,  p.  206),  the  case  of  a  humming-bird,  like  the  following  one  of 
Eustephanus. 


^  luc  luiiuwiug  auuitioiiai  uases  uiay  ue  uieiiLioiieu:  m 
Tanagra  inibra  can  be  distinguished  from  the  young  f« 
"  Ornith.  Biography,*'  vol.  iv,  p.  31)2),  and  so  it  is  within  the 
nuthatch,  iJendiophila  froniahs,  of  India  (Jerdon,  "  Birds  c 


656  THE  DESCENT  OF  MAN. 

We  have  now  see  in  all  six  classes  that  an  intimate  rela- 
tion exists  between  the  plumage  of  the  young  and  the 
adults,  either  of  one  sex  or  both.  These  relations  are 
fairly  well  explained  on  the  principle  that  one  sex — this 
being  in  the  great  majority  of  cases  the  male — first  acquired 
through  variation  and  sexual  selection  bright  colors  or 
other  ornaments  and  transmitted  them  in  various  ways  in 
accordance  with  tlie  recognized  laws  of  inheritance.  Why 
variations  have  occurred  at  different  periods  of  life,  even 
sometimes  with  species  of  the  same  group,  we  do  not  know, 
but  with  respect  to  the  form  of  transmission  one  important 
determining  cause  seems  to  be  the  age  at  which  the  varia- 
tions first  appear. 

From  the  principle  of  inheritance  at  corresponding  ages 
and  from  any  variations  in  color  which  occurred  in  the 
males  at  an  early  age  not  being  then  selected — on  the  con- 
trary being  often  eliminated  as  dangerous — while  similar 
variations  occurring  at  or  near  the  period  of  reproduction 
have  been  preserved,  it  follows  that  the  plumage  of  the 
young  will  often  have  been  left  unmodified,  or  but  little 
modified.  We  thus  get  some  insight  into  the  coloring  of 
the  progenitors  of  our  existing  species.  In  a  vast  number 
of  species  in  five  out  of  our  six  classes  of  cases  the  adults  of 
one  sex  or  of  both  are  bright  colored,  at  least  during  tHe 
breeding-season,  while  the  young  are  invariably  less  brightly 
colored  than  the  adults,  or  are  quite  dull  colored;  for  no 
instance  is  known,  as  far  as  I  can  discover,  of  the  young  of 
dull-colored  species  displaying  bright  colors,  or  of  the  young 
of  bright-colored  species  being  more  brilliant  than  their 
parents.  In  the  fourth  class,  however,  in  which  the  young 
and  the  old  resemble  each  other,  there  are  many  species 
(though  by  no  means  all),  of  which  the  young  are  bright 
colored,  and,  as  these  form  old  groups,  we  may  infer  that 
their  early,  progenitors  were  likewise  bright.  With  this 
exception,  if  we  look  to  the  birds  of  the  world,  it  appears 
that  their  beauty  has  been  much  increased  since  that 
period,  of  which  their  immature  plumage  gives  us  a  partial 
record. 

On  the  Color  of  the  Plumage  in  Relatio7i  to  Protection. — 
It  will  have  been  seen  that  I  cannot  follow  Mr.  Wallace  in 
the  belief  that  dull  colors,  when  confined  to  the  females, 
have  been  in  most  cases  specially  gained  for  the  sake  of 


BIRDS.  557 

protection.  There  can,  however,  be  no  doubt,  as  formerly 
remarked,  that  both  sexes  of  many  birds  have  had  their 
colors  modified  so  as  to  escape  the  notice  of  their  enemies; 
or  in  some  instances,  so  as  to  approach  their  prey  unobserved, 
just  as  owls  have  had  their  plumage  rendered  soft,  that 
their  flight  may  not  be  overheard.  Mr.  Wallace  remarks  * 
that  "  it  is  only  in  the  tropics,  among  forests  which  never 
lose  their  foliage,  that  we  find  whole  groups  of  birds  whose 
chief  color  is  green."  It  will  be  admitted  by  every  one 
who  has  ever  tried  how  difficult  it  is  to  distinguish  parrots 
in  a  leaf-covered  tree.  T^everthelesss,  we  must  remember 
that  many  parrots  are  ornamented  with  crimson,  blue  and 
orange  tints,  which  can  hardly  be  protective.  AVood peckers 
are  eminently  arboreal,  but  besides  green  species  there  are 
many  black  and  black-and-white  kinds — all  the  species 
being  apparently  exposed  to  nearly  the  same  dangers.  It 
is  therefore  probable  that  with  tree-haunting  birds  strongly 
pronounced  colors  have  been  acquired  through  sexual  selec- 
tion, but  that  a  green  tint  has  been  acquired  oftener  than 
any  other  from  the  additional  advantage  of  protection. 

In  regard  to  birds  which  live  on  the  ground,  every  one 
admits  that  they  are  colored  so  as  to  imitate  the  surround- 
ing surface.  3ow  difficult  it  is  to  see  a  partridge,  snipe, 
woodcock,  certain  plovers,  larks  and  night- jars  when 
crouched  on  ground.  Animals  inhabiting  deserts  offer  the 
most  striking  cases,  for  the  bare  surface  affords  no  conceal- 
ment, and  nearly  all  the  smaller  quadrupeds,  reptiles  and 
birds  depend  for  safety  on  their  colors.  Mr.  Tristram  has 
remarked  in  regard  to  the  inhabitants  of  the  Sahara,  that 
all  are  protected  by  their  "  isabelline  or  sand  color,  "f 
Calling  to  my  recollection  the  desert-birds  of  South 
America,  as  well  as  most  of  the  ground-birds  of  Great 
Britain,  it  appeared  to  me  that  both  sexes  in  such  cases 
are  generally  colored  nearly  alike.  Accordingly,  I  applied 
to  Mr.  Tristram  with  respect  to  the  birds  of  the  Sahara, 
and  he  has  kindly  given  me  the  following  information: 
There  are  twenty-six  species  belonging  to  fifteen  genera, 
which  manifestly  have  their  plumage  colored  in  a  protect- 

♦  "  Westminster  Review,"  July,  1867,  p.  5. 

f  "  Ibis,"  1859,  vol.  i,  p.  429,  et  seq.  Dr.  Rohlfs,  however,  re- 
marks to  me  in  a  letter  that,  according  to  his  experience  of  the 
Sahara,  this  statement  is  too  strong. 


558  THE  DESCENT  OF  MAN, 

ive  manner;  and  this  coloring  is  all  the  more  striking,  as 
with  most  of  tliese  birds  it  differs  from  that  of  their  con- 
geners. Both  sexes  of  thirteen  out  of  the  twenty-six 
species  are  colored  in  the  same  manner;  but  these  belong 
to  genera  in  which  this  rule  commonly  prevails,  so  that 
they  tell  us  nothing  about  the  protective  colors  being  the 
same  in  both  sexes  of  desert-birds.  Of  tlie  other  thirteen 
species  three  belong  to  genera  in  which  the  sexes  usually 
differ  from  each  other,  yet  here  they  have  the  sexes  alike. 
In  the  remaining  ten  species  the  male  differs  from  the 
female;  but  the  difference  is  confined  chiefly  to  the  under 
surface  of  the  plumage,  which  is  concealed  when  the  bird 
crouches  on  the  ground;  the  head  and  back  being  of  the 
same  sand-colored  hue  in  the  two  sexes.  So  that  in  these 
ten  species  the  upper  surfaces  of  both  sexes  have  been  acted 
on  and  rendered  alike  through  natural  selection  for  the 
sake  of  protection;  while  tlie  lower  surfaces  of  the  males 
alone  have  been  diversified  through  sexual  selection  for  the 
sake  of  ornament.  Here,  as  both  sexes  are  equally  well 
protected,  we  clearly  see  that  the  females  have  not  been 
prevented  by  natural  selection  from  inheriting  the  colors  of 
their  male  parents ;  so  that  we  must  look  to  the  law  of 
sexually  limited  transmission. 

In  all  parts  of  the  world  both  sexes  of  many  soft-billed 
birds,  especially  those  which  frequent  reeds  or  hedges,  are 
obscurely  colored.  No  doubt  if  their  colors  had  been 
brilliant,  they  would  have  been  much  more  conspicuous  to 
their  enemies;  but  whether  their  dull  tints  have  been 
specially  gained  for  the  sake  of  protection  seems,  as  far  as 
I  can  judge,  rather  doubtful.  It  is  still  more  doubtful 
whether  such  dull  tints  can  have  been  gained  for  the  sake 
of  ornament.  We  must,  however,  bear  in  mind  that  male 
birds,  though  dull-colored,  often  differ  much  from  their 
females  (as  with  the  common  sparrow),  and  this  leads  to 
the  belief  that  such  colors  have  been  gained  through  sexual 
selection  from  being  attractive.  Many  of  the.  soft-billed 
birds  are  songsters;  and  a  discussion  in  a  former  chapter 
should  not  be  forgotten,  in  which  it  was  shown  that  the 
best  songsters  are  rarely  ornamented  with  bright  tints.  It 
would  appear  that  female  birds,  as  a  general  rule,  have 
selected  their  mates  either  for  their  sweet  voices  or  gay 
colors,  but  not  for  both  charms  combined.  Some  species 
which  are  manifestly  colored  for  the  sake  of  protection, 


BIRDS.  559 

such  as  the  jack-snipe,  woodcock  and  night- jar,  are  like- 
wise marked  and  shaded,  according  to  our  standard  of 
taste,  with  extreme  elegance.  In  such  cases  we  may  con- 
clude that  both  natural  and  sexual  selection  have  acted 
conjointly  for  protection  and  ornament.  Whether  any 
bird  exists  which  does  not  possess  some  special  attraction 
by  which  to  charm  the  opposite  sex  may  be  doubted. 
When  both  sexes  are  so  obscurely  colored  that  it  would 
be  rash  to  assume  the  agency  of  sexual  selection,  and  when 
no  direct  evidence  can  be  advanced  showing  that  such 
colors  serve  as  a  protection,  it  is  best  to  own  complete 
ignorance  of  the  cause,  or,  which  comes  to  nearly  the  same 
thing,  to  attribute  the  result  to  the  direct  action  of  the 
conditions  of  life. 

Both  sexes  of  many  birds  are  conspicuously,  though  not 
brilliantly,  colored,  such  as  the  numerous  black,  white,  or 
piebald  species;  and  these  colors  are  probably  the  result  of 
sexual  selection.  With  the  common  blackbird,  capercailzie, 
blackcock,  black  scoter-duck  (Oidemia),  and  even  with  one 
of  tlie  birds  of  paradise  {LopJiorina  air  a)  the  males  alone 
are  black,  while  the  females  are  brown  or  mottled;  and 
there  can  hardly  be  a  doubt  that  blackness  in  these  cases 
has  been  a  sexually  selected  character.  Therefore,  it  is  in 
some  degree  probable  that  the  complete  or  partial  blackness 
of  both  sexes  in  such  birds  as  crows,  certain  cockatoos, 
storks  and  swans,  and  many  marine  birds,  is  likewise  the 
result  of  sexual  selection,  accompanied  by  equal  transmis- 
sion to  both  sexes;  for  blackness  can  hardly  serve  in  any 
case  as  a  protection.  With  several  birds,  in  which  the  male 
alone  is  black,  and  in  others  in  which  both  sexes  are  black, 
the  beak  or  skin  about  the  head  is  brightly  colored,  and 
the  contrast  thus  afforded  adds  much  to  their  beauty;  we 
see  this  in  the  bright  yellow  beak  of  the  male  blackbird,  in 
the  crimson  skin  over  the  eyes  of  the  blackcock  and  caper- 
cailzie, in  the  brightly  and  variously  colored  beak  of  the 
scoter-drake  (Oidemia),  in  the  red  beak  of  the  chough 
(Corvus graculiis,  Linn.),  of  the  black  swan  and  the  black 
stork.  This  leads  me  to  remark  that  it  is  not  incredible 
that  toucans  may  owe  the  enormous  size  of  their  beaks  to 
sexual  selection,  for  the  sake  of  displaying  the  diversified 
and  vivid  stripes  of  color  with  wliich  these  organs  are 
ornamented.*     The  naked  skin,  also,  at  the  base  of  the 

*  No  satisfactory  explanation  has  ever  been  offered  of  the  immense 


560  THE  DESCENT  OF  MAN. 

beak  and  round  the  eyes  is  likewise  often  brilliantly  colored; 
and  Mr.  Gould,  in  speaking  of  one  species,*  says  that  the 
colors  of  the  beak  ''are  doubtless  in  the  finest  and  most 
brilliant  state  during  the  time  of  pairing."  There  is  no 
greater  improbability  that  toucans  should  be  encumbered 
with  immense  beaks,  though  rendered  as  light  as  possible 
by  their  cancellated  structure,  for  the  display  of  fine 
colors  (an  object  falsely  appearing  to  us  unimportant), 
than  that  the  male  Argus  pheasant  and  some  other  birds 
should  be  encumbered  with  plumes  so  long  as  to  impede 
their  flight. 

In  the  same  manner,  as  the  males  alone  of  various  species 
are  black,  the  females  being  dull-colored;  so  in  a  few  cases 
the  males  alone  are  either  wholly  or  partially  white,  as  with 
the  several  bell-birds  of  South  America  (Chasmorhynchus), 
the  Antarctic  goose  (Bernida  antarctica),  the  silver  pheas- 
ant, etc.,  while  the  females  are  brown  or  obscurely  mottled. 
Therefore,  on  the  same  principle  as  before,  it  is  probable 
that  both  sexes  of  many  birds,  such  as  white  cockatoos, 
several  egrets  with  their  beautiful  plumes,  certain  ibises, 
gulls,  terns,  etc.,  have  acquired  their  more  or  less  com- 
pletely white  plumage  through  sexual  selection.  In  some 
of  these  cases  the  plumage  becomes  white  only  at  maturity. 
This  is  the  case  with  certain  gannets,  tropic-birds,  etc., 
and  with  the  snow-goose  (Anser  hyperborei(s).  As  the 
latter  breeds  on  the  ''barren  grounds,"  when  not  covered 
with  snow,  and  as  it  migrates  southward  during  the  winter 
there  is  no  reason  to  suppose  that  its  snow-white  adult 
plumage  serves  as  a  protection.  In  the  Anastomus  oscitans 
we  have  still  better  evidence  that  the  white  plumage  is  a 
nuptial   character,    for  it  is   developed   only   during  the 

size,  and  still  less  of  the  bright  colors,  of  the  toucan's  beak.  Mr. 
Bates  ("  The  Naturalist  on  the  Amazons,"  vol.  ii,  1863,  p.  341)  states 
that  they  use  their  beaks  for  reaching  fruit  at  the  extreme  tips  of  the 
branches;  and  likewise,  as  stated  by  other  authors,  for  extracting 
eggs  and  young  birds  from  the  nests  of  other  birds.  But,  as  Mr. 
Bates  admits,  the  beak  "  can  scarcely  be  considered  a  very  perfectly 
formed  instrument  for  the  end  to  which  it  is  applied."  The  great 
bulk  of  the  beak,  as  shown  by  its  breadth,  depth,  as  well  as  length, 
is  not  intelligible  on  the  view,  that  it  serves  merely  as  an  organ  of 
prehension.  Mr.  Belt  believes  ("  The  Naturalist  in  Nicaragua,"  p. 
197)  that  the  principal  use  of  the  beak  is  as  a  defense  against 
enemies,  especially  to  the  female  while  nesting  in  a  hole  in  a  tree.  ^ 
* Rhamphastos carinatus,  Gould's  "Monograph  of  Bhamphastidse." 


BIRDS.  561 

summer;  the  young  in  their  immature  state  and  the  adults 
in  their  winter  dress  heing  gray  and  black.  With  many 
kinds  of  gulls  (Larus)  the  head  and  neck  become  pure 
white  during  the  summer,  being  gray  or  mottled  during 
the  winter  and  in  the  young  state.  On  the  other  hand, 
with  the  smaller  gulls,  or  sea-mews  (Gavia)  and  with  some 
terns  (Steraa)  exactly  the  reverse  occurs;  for  the  heads  of 
the  young  birds  during  the  first  year,  and  of  the  adults  during 
the  winter,  are  either  pure  white  or  much  paler  colored 
than  during  the  breeding-season.  These  latter  cases  offer 
another  instance  of  the  capricious  manner  in  which  sexual 
selection  appears  often  to  have  acted.* 

That  aquatic  birds  have  acquired  a  white  plumage  so 
much  oftener  than  terrestrial  birds  probably  depends  on 
their  large  size  and  strong  powers  of  flight,  so  that  they 
can  easily  defend  themselves  or  escape  from  birds  of  prey, 
to  which,  moreover,  they  are  not  much  exposed.  Conse- 
quently sexual  selection  has  not  here  been  interfered  with 
or  guided  for  the  sake  of  protection.  No  doubt  with  birds 
which  roam  over  the  open  ocean,  the  males  and  females 
could  find  each  other  much  more  easily  when  made  con- 
spicuous either  by  being  perfectly  white  or  intensely  black; 
so  that  these  colors  may  possibly  serve  the  same  end  as  the 
call-notes  of  many  land-birds,  f  A  white  or  black  bird 
when  it  discovers  and  flies  down  to  a  carcass  floating  on  the 
sea  or  cast  upon  the  beach,  will  be  seen  from  a  great  dis- 
tance, and  will  guide  other  birds  of  the  same  and  other 
species  to  the  prey;  but  as  this  would  be  a  disadvantage  to 
the  first  finders,  the  individuals  which  were  the  whitest  or 
blackest  would  not  thus  procure  more  food  than  the  less 
strongly  colored  individuals.  Hence  conspicuous  colors 
cannot  have  been  gradually  acquired  for  this  purpose 
through  natural  selection. 

As  sexual  selection  depends  on  so  fluctuating  an  element 

*0n  Larus,  Gavia  and  Sterna,  see  Macgillivray,  "Hist.  Brit. 
Birds,"  vol.  v,  pp.  515,  584,  626.  On  the  Anser  liyperboreus,  Audu- 
bon, "  Ornith.  Biography,"  vol.  iv,  p.  562.  On  the  Anastomus,  Mr. 
Blyth,  in  "  Ibis,"  1867,  p.  173. 

f  It  may  be  noticed  that  with  vultures,  which  roam  far  and  wide 
high  in  the  air,  like  marine  birds  over  the  ocean,  three  or  four  species 
are  almost  wholly  or  largely  white,  and  that  many  others  are  black. 
So  that  here  again  conspicuous  colors  may  possibly  aid  the  sexes  in 
finding  each  other  during  the  breeding  season. 


562  THE  DESCENT  OF  MAN. 

as  taste,  we  can  understand  how  it  is  tliat,  within  the  same 
group  of  birds  having  nearly  the  same  habits,  there  sliould 
exist  white  or  nearly  white,  as  well  as  black  or  nearly  black, 
species — for  instance,  both  white  and  black  cockatoos, 
storks,  ibises,  swans,  terns  and  petrels.  Piebald  birds  like- 
wise sometimes  occur  in  the  same  groups  together  with 
black  and  white  species;  for  instance,  the  black-necked 
swan,  certain  terns  and  the  common  magpie.  That  a  strong 
contrast  in  color  is  agreeable  to  birds  we  may  conclude  by 
looking  through  any  large  collection,  for  the  sexes  often 
diifer  from  each  other  in  the  male  having  the  pale  parts  of 
a  purer  white,  and  the  variously  colored  dark  parts  of  still 
darker  tints  than  the  female. 

It  would  even  appear  that  mere  novelty,  or  slight 
changes  for  the  sake  of  change,  have  sometimes  acted  on 
female  birds  as  a  charm,  like  changes  of  fashion  with  us. 
Thus  the  males  of  some  parrots  can  hardly  be  said  to  be 
more  beautiful  than  the  females,  at  least  according  to  our 
feste,  but  they  differ  in  such  points,  as  in  having  a  rose- 
colored  collar  instead  of  ^'a  bright,  emeraldine,  narrow 
green  collar;"  or  in  the  male  having  a  black  collar  instead 
of  *^a  yellow  demi-collar  in  front,"  with  a  pale  roseate 
instead  of  a  plum-blue  head.*  As  so  many  male  birds 
have  elongated  tail-feathers  or  elongated  crests  for  their 
chief  ornament,  the  shortened  tail,  formerly  described  in 
the  male  of  a  humming-bird,  and  the  shortened  crest  of 
the  male  goosander,  seem  like  one  of  the  many  changes  of 
fashion  which  we  admire  in  our  own  dresses. 

Some  members  of  the  heron  family  offer  a  still  more 
curious  case  of  novelty  in  coloring,  having,  as  it  appears, 
been  appreciated  for  the  sake  of  novelty.  The  young  of 
the  Ardea  aslia  are  white,  the  adults  being  dark  slate- 
colored;  and  not  only  the  young,  but  the  adults  in  their 
winter  plumage,  of  the  allied  Btiphus  coromandns  are 
white,  this  color  changing  into  a  rich  golden-buff  during 
the  breeding-season.  It  is  incredible  that  the  young  of 
these  two  species,  as  well  as  of  some  other  members  of  the 
same  family, f   should  for  any  special  purpose  have  been 

*See  Jerdon  on  the  genus  Palaeornis,  "  Birds  of  India,"  vol.  i,  pp. 
25i^260. 

f  The  young  of  Ardea  rufescens  and  A.  cosrulea  of  the  United 
States  are  likewise  white,  the  adults  being  colored  in  accordauQe 


BIRDS.  563 

rendered  pure  white  and  thus  made  conspicuous'  to  their 
enemies;  or  that  the  adults  of  one  of  these  two  species 
should  have  been  specially  rendered  white  during  the 
winter  in  a  country  which  is  never  covered  with  snow.  On 
the  other  hand,  we  have  good  reason  to  believe  that  white- 
ness has  been  gained  by  many  birds  as  a  sexual  ornament. 
We  may  therefore  conclude  that  some  early  progenitor  of 
the  Ardea  asha  and  the  Buphus  acquired  a  white  plumage 
for  nuptial  purposes,  and  transmitted  this  color  to  their 
young;  so  that  the  young  and  the  old  became  white  like 
certain  existing  egrets;  and  that  the  whiteness  was  after- 
ward retained  by  the  young,  while  it  was  exchanged  by  the 
adults  for  more  strongly  pronounced  tints.  But  if  ^e 
could  look  still  further  back  to  the  still  earlier  progenitors 
of  these  two  species  we  should  probabh^  see  the  adults  dark- 
colored.  I  infer  that  this  would  be  the  case  from  the 
analogy  of  many  other  birds  which  are  dark  while  young 
and  when  adult  are  white;  and  more  especially  from  the 
case  of  the  Ardea  gularis,  the  colors  of  which  are  the 
reverse  of  those  of  A.  asha,  for  the  young  are  dark-colored 
and  the  adults  white,  the  young  having  retained  a  former 
state  of  plumage.  It  appears  therefore  that  during  a  long 
line  of  descent,  the  adult  progenitors  of  the  Ardea  asha, 
the  Buphus,  and  of  some  allies,  have  undergone  the  follow- 
ing changes  of  color:  fiistly,  a  dark  shade;  secondly,  pure 
white,  and  thirdly,  owing  to  another  change  of  fashion  (if 
I  may  so  express  myself),  their  present  slaty,  reddish,  or 
golden-bluff  tints.  These  successive  changes  are  intelligi- 
ble only  on  the  principle  of  novelty  having  been  admired 
by  birds  for  its  own  sake. 

Several  writers  have  objected  to  the  whole  theory  of 
sexual  selection  by  assuming  that  with  animals  and  savages 
the  taste  of  the  female  for  certain  colors  or  other  ornaments 
would  not  remain  constant  for  many  generations;  that  first 
one  color  and  then  another  would  be  admired,  and  conse- 
quently that  no  permanent  effect  could  be  produced.  We 
may  admit  that  taste  is  fluctuating,  but  it  is  not  quite  arbi- 
trary. It  depends  much  on  habit,  as  we  see  in  mankind  ; 
and  we  may  infer  that  this  would  hold  good  with  birds  and 

with  their  specific  names.  Audubon  ("  Ornith.  Biography,"  vol.  iii. 
p.  416;  vol.  iv,  p.  58)  seems  rather  pleased  at  the  thought  that  this 
remarkable  change  of  plumage  will  greatly  "  disconcert  the  system^ 
Atists." 


5G4  THE  DESCENT  OF  MAN. 

other  animals.  Even  in  our  own  dress  the  general  character 
lasts  long,  and  the  changes  are  to  a  certain  extent  gradu- 
ated. Abundant  evidence  will  be  given  in  two  places  in  a 
future  chapter  that  savages  of  many  races  have  admired  for 
many  generations  the  same  cicatrices  on  the  skin,  the  same 
hideously  perforated  lips,  nostrils,  or  ears,  distorted  heads, 
etc.;  and  these  deformities  present  some  analogy  to  the 
natural  ornaments  of  various  animals.  Nevertheless,  with 
savages  such  fashions  do  not  endure  forever,  as  we  may 
infer  from  the  differences  in  this  respect  between  allied 
tribes  on  the  same  continent.  So,  again,  the  raisers  of 
fancy  animals  certainly  have  admired  for  many  generations 
and  still  admire  the  same  breeds;  they  earnestly  desire 
slight  changes,  which  are  considered  as  improvements,  but 
any  great  or  sudden  change  is  looked  at  as  the  greatest 
blemish.  With  birds  in  a  state  of  nature  we  have  no 
reason  to  suppose  that  they  would  admire  an  entirely  new 
style  of  coloration,  even  if  great  and  sudden  variations 
often  occurred,  which  is  far  from  being  the  case.  We  know 
that  dove-cote  pigeons  do  not  willingly  associate  with  the 
variously  colored  fancy  breeds;  that  albino  birds  do  not 
commonly  get  partners  in  marriage;  and  that  the  black 
ravens  of  the  Feroe  Islands  chase  away  their  piebald 
brethren.  But  this  dislike  of  a  sudden  change  would  not 
preclude  their  appreciating  slight  changes  any  more  than  it 
does  in  the  case  of  man.  Hence,  with  respect  to  taste, 
which  depends  on  many  elements,  but  partly  on  habit  and 
partly  on  a  love  of  novelty,  there  seems  no  improba- 
bility in  animals  admiring  for  a  very  long  period  the 
same  general  style  of  ornamentation  or  other  attractions, 
and  yet  appreciating  slight  changes  in  colors,  form,  or 
sound. 

Summary  of  the  Four  Chapters  on  Birds. — Most  male 
birds  are  highly  pugnacious  during  the  breeding-season,  and 
some  possess  weapons  adapted  for  fighting  with  their  rivals. 
But  the  most  pugnacious  and  the  best  armed  males  rarely 
or  never  depend  for  success  solely  on  their  power  to  drive 
away  or  kill  their  rivals,  but  have  special  means  for  charm- 
ing the  female.  With  some  it  is  the  power  of  song,  or  of 
giving  forth  strange  cries,  or  instrumental  music,  and  the 
males  in  consequence  differ  from  the  females  in  their  vocal 
organs,  or  in  the  structure  of  certain  feathers.     From  the 


BIRDS.  666 

curiously  diversified  means  for  producing  vanous  sounds  we 
gain  a  high  idea  of  the  importance  of  this  means  of  court- 
ship. Many  birds  endeavor  to  charm  the  females  by  love 
dances  or  antics  performed  on  the  ground  or  in  the  air,  and 
sometimes  at  prepared  places.  But  ornaments  of  many 
kinds,  the  most  brilliant  tints,  combs  and  wattles,  beautiful 
plumes,  elongated  feathers,  top-knots,  and  so  forth,  are  by 
far  the  commonest  means.  In  some  cases  mere  novelty 
appears  to  have  acted  as  a  charm.  The  ornaments  of  the 
males  must  be  highly  important  to  them,  for  they  have 
been  acquired  in  not  a  few  cases  at  the  cost  of  increased 
danger  from  enemies,  and  even  at  some  loss  of  power  in 
fighting  with  their  rivals.  The  males  of  very  many  species 
do  not  assume  their  ornamental  dress  until  they  arrive  at 
maturity,  or  they  assume  it  only  during  the  breeding-season, 
or  the  tints  then  become  more  vivid.  Certain  ornamental 
appendages  become  enlarged,  turgid,  and  brightly  colored 
during  the  act  of  courtship.  The  males  display  their 
charms  with  elaborate  care  and  to  the  best  effect;  and  this 
is  done  in  the  presence  of  the  females.  The  courtship  is 
sometimes  a  prolonged  affair,  and  many  males  and  females 
congregate  at  an  appointed  place.  To  suppose  that  the 
females  do  not  appreciate  the  beauty  of  the  males  is  to 
admit  that  their  splendid  decorations,  all  their  pomp  and 
display,  are  useless;  and  this  is  incredible.  Birds  have  fine 
powers  of  discrimination,  and  in  some  few  instances  it  can 
be  shown  that  they  have  a  taste  for  the  beautiful.  The 
females,  moreover,  are  known  occasionally  to  exhibit  a 
marked  preference  or  antipathy  for  certain  individual 
males. 

If  it  be  admitted  that  the  females  prefer,  or  are  uncou- 
sciously  excited  by  the  more  beautiful  males,  then  the 
males  would  slowly  but  surely  be  rendered  more  and  more 
attractive  through  sexual  selection.  That  it  is  this  sex 
which  has  been  chiefly  modified,  we  may  infer  from  the 
fact  that,  in  almost  every  genus  where  the  sexes  differ,  the 
males  differ  much  more  from  one  another  than  do  the 
females;  this  is  well  shown  in  certain  closely  allied  repre- 
sentative species,  in  which  the  females  can  hardly  be  dis- 
tinguished, while  the  males  are  quite  distinct.  Birds  in  a 
state  of  nature  offer  individual  differences  which  would 
am  pi}'  suffice  for  the  work  of  sexual  selection;  but  we  have 
seeu  that  they  occasionally  present  more  strongly  marked 


566  THE  DESCENT  OF  MAN. 

variations  which  recur  so  frequently  that  they  would  imme- 
diately be  fixed,  if  they  served  to  allure  the  female.  The 
laws  of  variation  must  determine  the  nature  of  the  initial 
changes,  and  will  have  largely  influenced  the  final  result. 
The  gradations,  which  may  be  observed  between  the  males 
of  allied  species,  indicate  the  nature  of  the  steps  through 
which  they  have  passed.  They  explain  also  in  the  most 
interesting  manner  how  certain  characters  have  originated, 
such  as  the  indented  ocelli  on  the  tail-feathers  of  the  pea- 
cock, and  the  ball-and-socket  ocelli  on  the  wing-feathers 
of  the  Argus  pheasant.  It  is  evident  that  the  brilliant 
colors,  top-knots,  fine  plumes,  etc.,  of  many  male  birds 
cannot  have  been  acquired  as  a  protection;  indeed,  they 
sometimes  lead  to  danger.  That  they  are  not  due  to  the 
direct  and  definite  action  of  the  conditions  of  life,  we  may 
feel  assured,  because  the  females  have  been  exposed  to  the 
same  conditions,  and  yet  often  differ  from  the  males  to  an 
extreme  degree.  Although  it  is  probable  that  changed 
conditions  acting  during  a  lengthened  period  have  in  some 
cases  produced  a  definite  effect  on  both  sexes,  or  some- 
times on  one  sex  alone,  the  more  important  result  will  have 
been  an  increased  tendency  to  vary  or  to  present  more 
strongly  marked  individual  differences;  and  such  differ- 
ences will  have  afforded  an  excellent  groundwork  for  the 
action  of  sexual  selection. 

The  laws  of  inheritance,  irrespectively  of  selection, 
appear  to  have  determined  whether  the  characters  acquired 
by  the  males  for  the  sake  of  ornament,  for  producing  vari- 
ous sounds  and  for  fighting  together,  have  been  transmitted 
to  the  males  alone  or  to  both  sexes  either  permanently  or 
periodically  during  certain  seasons  of  the  year.  Why 
various  characters  should  have  been  transmitted  sometimes 
in  one  way  and  sometimes  in  another  is  not  in  most  cases 
known;  but  the  period  of  variability  seems  often  to  have 
been  the  determining  cause.  When  the  two  sexes  have 
inherited  all  characters  in  common  they  necessarily  resem- 
ble each  other;  but  as  the  successive  variations  may  be 
differently  transmitted  every  possible  gradation  may  be 
found,  even  within  the  same  genus,  from  the  closest  simi- 
larity to  the  widest  dissimilarity  between  the  sexes.  With 
many  closely  allied  species,  following  nearly  the  same 
habits  of  life,  the  males  have  come  to  differ  from  each 
other  chiefly  through  the  action  of  sexual  selection;  while 


BIRDS.  567 

the  females  have  come  to  differ  chiefly  from  partaking 
more  or  less  of  the  characters  thus  acquired  by  the  males. 
The  effects,  moreover,  of  the  definite  action  of  the  condi- 
tions of  life  will  not  have  been  masked  in  the  females  as 
in  the  males  by  the  accumulation  through  sexual  selection 
of  strongly  pronounced  colors  and  other  ornaments.  The 
individuals  of  both  sexes,  however  affected,  will  have  been 
kept  at  each  successive  period  nearly  uniform  by  the  free 
intercrossing  of  many  individuals. 

With  species  in  which  the  sexes  differ  in  color  it  is  possi- 
ble or  probable  that  some  of  the  successive  variations  often 
tended  to  be  transmitted  equally  to  both  sexes;  but  that 
when  this  occurred  the  females  were  prevented  from  acquir- 
ing the  bright  colors  of  the  males  by  the  destruction  which 
they  suffered  during  incubation.  There  is  no  evidence 
that  it  is  possible  by  natural  selection  to  convert  one  form 
of  transmission  into  another.  But  there  would  not  be  the 
least  difficulty  in  rendering  a  female  dull-colored,  the  male 
being  still  kept  bright-colored,  by  the  selection  of  suc- 
cessive variations  which  were  from  the  first  limited  in  their 
transmission  to  the  same  sex.  Whether  the  females  of" 
many  species  have  actually  been  thus  modified  must  at 
present  remain  doubtful.  When,  through  the  law  of  the 
equal  transmission  of  characters  to  both  sexes,  the  females 
were  rendered  as  conspicuously  colored  as  the  males,  their 
instincts  appear  often  to  have  been  modified  so  that  they 
were  led  to  build  domed  or  concealed  nests. 

In  one  small  and  curious  class  of  cases  the  characters 
and  habits  of  the  two  sexes  have  been  completely  trans- 
posed, for  the  females  are  larger,  stronger,  more  vociferous 
and  brighter  colored  than  the  males.  They  have  also  be- 
come so  quarrelsome  that  they  often  fight  together  for  the 
possession  of  the  males  like  the  males  of  other  pugnacious 
species  for  the  possession  of  the  females.  If,  as  seems 
•probable,  such  females  habitually  drive  aways  their  rivals, 
and  by  the  display  of  their  bright  colors  or  other  charms 
endeavor  to  attract  the  males,  we  can  understand  how  it  is 
that  they  have  gradually  been  rendered  by  sexual  selection 
and  sexually  limited  transmission  more  beautiful  than  the 
males — the  latter  being  left  unmodified  or  only  slightly 
modified. 

Whenever  the  law  of  inheritance  at  corresponding  ages 


568  T3E  DESCENT  OF  MAN. 

prevails,  but  not  that  of  sexually  limited  transmissson,  then 
if  the  parents  vary  late  in  life — and  we  know  that  this  con- 
stantly occurs  with  our  poultry  and  occasionally  with  other 
birds — the  young  will  be  left  unaffected,  while  the  adults 
of  both  sexes  will  be  modified.  If  both  these  laws  of 
inheritance  prevail  and  either  sex  varies  late  in  life,  that 
sex  alone  will  be  modified,  the  other  sex  and  the  young 
being  unaffected.  When  variations  in  brightness  or  in 
other  conspicuous  characters  occur  early  in  life,  as  no  doubt 
often  happens,  they  will  not  be  acted  on  through  sexual 
selection  until  the  period  of  reproduction  arrives;  conse- 
quently if  dangerous  to  the  young  they  will  be  eliminated 
through  natural  selection.  Thus  we  can  understand  how 
it  is  that  variations  arising  late  in  life  have  so  often  been 
preserved  for  the  ornamentation  of  the  males;  the  females 
and  the  young  being  left  almost  unaffected,  and  therefore 
like  each  other.  With  species  having  a  distinct  summer 
and  winter  plumage,  the  males  of  which  either  resemble  or 
differ  from  the  females  during  both  seasons  or  during  the 
summer  alone,  the  degrees  and  kinds  of  resemblance 
between  the  young  and  the  old  are  exceedingly  complex; 
and  this  complexity  apparently  depends  on  characters,  first 
acquired  by  the  males,  being  transmitted  in  various  ways 
and  degrees,  as  limited  by  age,  sex  and  season. 

As  the  young  of  so  many  species  have  been  but  little 
modified  in  color  and  in  other  ornaments,  we  are  enabled 
to  form  some  judgment  with  respect  to  the  plumage  of  their 
early  progenitors;  and  we  may  infer  that  the  beauty  of  our 
existing  species,  if  we  look  to  the  whole  class,  has  been 
largely  increased  since  that  period,  of  which  the  immature 
plumage  gives  us  an  indirect  record.  Many  birds,  espe- 
cially those  which  live  much  on  the  ground,  have  undoubt- 
edly been  obscurely  colored  for  the  sake  of  protection.  In 
some  instances  the  upper  exposed  surface  of  the  plumage 
has  been  thus  colored  in  both  sexes,  while  the  lower  surface 
in  the  males  alone  has  been  variously  ornamented  through 
sexual  selection.  Finally,  from  the  facts  given  in  these 
four  chapters,  we  may  conclude  that  weapons  for  battle, 
organs  for  producing  sound,  ornaments  of  many  kinds, 
bright  and  conspicuous  colors,  have  generally  been  acquired 
by  the  males  through  variation  and  sexual  selection  and 
have  been  transmitted  in  various  ways  according  to  the 


BIRDS,  569 

several  laws  of  inheritance — the   females  and  the  young 
being  left  comparatively  but  little  modified.* 

*  I  am  greatly  indebted  to  the  kindness  of  Mr.  Sclater  for  having 
looked  over  these  four  chapters  on  birds,  and  the  two  following  ones 
on  mammals.  In  this  way  I  have  been  saved  from  making  mistakes 
about  the  names  of  the  species,  and  from  stating  anything  as  a  fact 
■which  is  known  to  this  distinguished  naturalist  to  be  erroneous. 
But  of  course  he  is  not  at  all  answerable  for  the  accuracy  of  the 
statements  quoted  by  me  from  various  authorities. 


5tO  ^^^  DESCENT  OF  MAN. 


CHAl^TEli  XVII. 
SlCOKDABY  SEXUAL  CHARACTERS  OF  MAMMALS. 

The  law  of  battle — Special  weapons,  confined  to  the  males — Cause  of 
absence  of  weapons  in  the  female— Weapons  common  to  both 
sexes,  yet  primarily  acquired  by  the  male — Other  uses  of  such 
weapons — Their  high  importance — Greater  size  of  the  male — 
Means  of  defense — On  the  preference  shown  by  either  sex  in  the 
pairing  of  quadrupeds. 

With  mammals  the  male  appears  to  win  the  female 
much  more  through  the  law  of  battle  than  through  the 
display  of  his  charms.  The  most  timid  animals,  not  pro- 
vided with  any  special  weapons  for  fighting,  engage  in  des- 
perate conflicts  during  the  season  of  love.  Two  male  hares 
have  been  seen  to  fight  together  until  one  was  killed;  male 
moles  often  fight,  and  sometimes  with  fatal  results  ;  male 
squirrels  engage  in  frequent  contests,  "and  often  wound 
each  other  severely;"  as  do  male  beavers,  so  that  "hardly 
a  skin  is  without  scars. ^^*  I  observed  the  same  fact  with 
the  hides  of  the  guanacoes  in  Patagonia;  and  on  one  occa- 
sion several  were  so  absorbed  in  fighting  that  they  fear- 
lessly rushed  close  by  me.  Livingstone  speaks  of  the  males 
of  the  many  animals  in  Southern  Africa  as  almost  invari- 
ably showing  the  scars  received  in  former  contests. 

The  law  of  battle  prevails  with  aquatic  as  with  terrestrial 
mammals.  It  is  notorious  how  desperately  male  seals  fight, 
both  with  their  teeth  and  claws,  during  the  breeding- 
season  ;  and  their  hides  are  likewise  often  covered  with 
scars.  Male  sperm-whales  are  very  jealous  at  this  season; 
and  in  their  battles  "they  often  lock  their  jaws  together 

*See  Waterton's  account  of  two  hares  fighting,  "Zoologist,"  vol. 
i,  1843,  p  211.  On  moles.  Bell,  ='Hist.  of  British  Quadrupeds,"  1st 
edit.,  p.  100.  On  squirrels,  Audubon  and  Bachman,  Viviparous 
Quadrupeds  of  North  America,"  1846,  p.  269.  On  beavers,  Mr.  A. 
H.  Green,  in  "  Journal  of  Lin.  Soc.  Zoolog.,"  vol.  x,  1869,  p.  362. 


mammaljs.  sn 

and   turn   on   their   sides  and  twist  about;"  so  that  their 
lower  jaws  often  become  distorted.* 

All  male  animals  which  are  furnished  with  special  weap^ 
ons  for  fighting  are  well  known  to  engage  in  fierce  battles. 
The  courage  and  the  desperate  conflicts  of  stags  have  often 
been  described;  their  skeletons  have  been  found  in  various 
parts  of  the  world,  with  the  horns  inextricably  locked 
together,  showing  how  miserably  the  victor  and  vanquished 
had  perished,  f  No  animal  in  the  world  is  so  dangerous  as 
an  elephant  in  must.  Lord  Tankerville  has  given  me  a 
graphic  description  of  the  battles  between  the  wild  bulk 
in  Chillingham  Park,  the  descendants,  degenerated  in  size 
but  not  in  courage,  of  the  gigantic  Jios  primigenius. 
In  1861  several  contended  for  master}^;  and  it  was  observed 
that  two  of  the  younger  bulls  attacked  in  concert  the  old 
leader  of  the  herd,  overthrew  and  disabled  him,  so  that  he 
was  believed  by  the  keepers  to  be  lying  mortally  wounded 
in  a  neighboring  wood.  But  a  few  days  afterward  one  of 
the  young  bulls  approached  the  wood  alone;  and  then  the 
"  monarch  of  the  chase,"  who  had  been  lashing  himself  up 
for  vengeance,  came  out,  and,  in  a  short  time,  killed  his 
antagonist.  He  then  quietly  joined  the  herd,  and  long  held 
undisputed  sway.  Admiral  Sir  B.  J.  Sulivan  informs  me 
that,  when  he  lived  in  the  Falkland  Islands,  he  imported  a 
young  English  stallion,  which  frequented  the  hills  near 
Port  William  with  eight  mares.  On  these  hills  there  were 
two  wild  stallions,  each  with  a  small  troop  of  mares;  "  and 
it  is  certain  that  these  stallions  would  never  have  approached 
each  other  without  fighting.  Both  had  tried  singly  to  fight 
the  English  horse  and  drive  away  his  mares,  but  had  failed. 
One  day  they  came  in  together  and  attacked  him.  This  was 
seen  by  the  capitan  who  had  charge  of  the  horses,  and  who, 
on   riding  to   tlie   spot,  found  one   of  the   two   stallions 

*0n  the  battles  of  seals,  see  Capt.  C.  Abbott,  in  "  Proc.  Zool. 
Soc.,"  1868,  p.  191;  also  Mr.  R.  Brown,  ibid,  1868,  p.  436;  also  L. 
Lloyd,  "Game  Birds  of  Sweden,"  1867,  p.  412,  also  Pennant.  On 
tbe  spenn- whale  see  Mr.  J.  H.  Thompson,  in  "Proc.  Zool.  Soc.," 
1867,  p.  246. 

f  See  Scrope  ("  Art  of  Deer-Stalking,"  p.  17)  on  the  locking  of  the 
horns  with  the  Cet'vus  elaplius.  Richardson,  in  "  Fauna  Bor.  Amer- 
icana," 1829,  p.  252,  says  that  the  wapiti,  moose  and  reindeer  have 
been  found  tlius  locked  together.  Sir  A.  Smith  found  at  the  Cape 
of  Good  Hope  the  skeletons  of  two  gnus  in  the  same  condition. 


572  TSE  DESCENT  OF  MAN. 

engaged  with  the  English  horse,  while  the  other  was  driv- 
ing away  the  mares,  and  had  already  separated  four  from 
the  rest.  The  capitan  settled  the  matter  by  driving  the 
whole  party  into  the  corral,  for  the  wild  stallions  would  not 
leave  the  mares." 

Male  animals  which  are  provided  with  efficient  cutting 
or  tearing  teeth  for  the  ordinary  purposes  of  life,  such  as 
the  carnivora,  insectivora,  and  rodents,  are  seldom  furnished 
with  weapons  especially  adapted  for  fighting  with  their  rivals. 
The  case  is  very  different  with  the  males  of  many  other 
animals.  We  see  this  in  the  horns  of  stags  and  of  certain 
kinds  of  antelopes  in  which  the  females  are  hornless.  With 
many  animals  the  canine  teeth  in  the  upper  or  lower  jaw, 
or  in  both,  are  much  larger  in  the  males  than  in  the 
females,  or  are  absent  in  the  latter,  with  the  exception 
sometimes  of  a  hidden  rudiment.  Certain  antelopes,  the 
musk-deer,  camel,  horse,  boar,  various  apes,  seals,  and  the 
walrus,  offer  instances.  In  the  females  of  the  walrus  the 
tusks  are  sometimes  quite  absent.*  In  the  male  elephant 
of  India  and  in  the  male  dugoug  \  the  upper  incisors  form 
offensive  weapons.  In  the  male  narwhal  the  left  canine 
alone  is  developed  into  the  well-known,  spirally-twisted,  so- 
called  horn,  which  is  sometimes  from  nine  to  ten  feet  in 
length.  It  is  believed  that  the  males  use  these  horns  for 
fighting  together;  for  *^an  unbroken  one  can  rarely  be  got, 
and  occasionally  one  may  be  found  with  the  point  of 
another  jammed  into  the  broken  place."!  ^^^^  tooth  on 
the  opposite  side  of  the  head  in  the  male  consists  of  a  rudi- 
ment about  ten  inches  in  length,  which  is  embedded  in  the 
jaw;  but  sometimes,  though  rarely,  both  are  equally  devel- 
oped on  the  two  sides.  In  the  female  both  are  always  rudi- 
mentary.    The  male  cachalot  has  a  larger  head  than  that 

*  Mr.  Laraont  ("Seasons  with  the  Sea-Horses,"  1861,  p.  143)  says 
that  a  good  tusk  of  the  male  walrus  weighs  four  pounds,  and  is 
longer  than  that  of  the  female,  which  weighs  about  three  pounds. 
The  males  are  described  as  fighting  ferociously.  On  the  occasional 
absence  of  the  tusks  in  the  female,  see  Mr.  R.  Brown,  "  Proc.  Zool. 
Soc,"  1868,  p.  429. 

f  Owen,  •'  Anatomy  of  Vertebrates,"  vol.  iii,  p.  283. 

tMr.  R.  Brown,  in  "Proc.  Zool.  Soc,"  1869,  p.  553.  See  Prof. 
Turner,  in  "  Journal  of  Anat.  and  Phys.,"  1872,  p.  76,  on  the  homo- 
logical  nature  of  these  tusks.  Also  Mr.  J.  W.  Clarke  on  two  tusks 
being  developed  in  the  males,  in  "  Proc.  Zoolog.  Soc.,"  1871,  p.  42. 


MAMMALS.  573 

of  the  female,  and  it  no  doubt  aids  him  in  his  aquatic 
battles.  Lastly,  the  adult  male  ornithorhynchus  is  provided 
with  a  remarkable  apparatus,  namely,  a  spur  on  the  fore 
leg,  closely  resembling  the  poison-lang  of  a  venomous 
Buake ;  but,  according  to  Harting,  the  secretion  from 
tlie  gland  is  not  poisonous ;  and  on  the  leg  of  the  female 
there  is  a  hollow,  apparently  for  the  reception  of  the  spur.* 

When  the  males  are  provided  with  weapons  which  in 
the  females  are  absent,  there  can  hardly  be  a  doubt  that 
these  serve  for  fighting  with  other  males;  and  that  they 
were  acquired  through  sexual  selection  and  were  transmitted 
to  the  male  sex  alone.  It  is  not  probable,  at  least  in  most 
cases,  that  the  females  have  been  prevented  from  acquiring 
Buch  weapons,  on  account  of  their  being  useless,  super- 
fluous, or  in  some  way  injurious.  On  the  contrary,  as  they 
are  often  used  by  the  males  for  various  purposes,  more  espe- 
cially as  a  defense  against  their  enemies,  it  is  a  surprising 
fact  that  they  are  so  poorly  developed,  or  quite  absent  in 
the  females  of  so  many  animals.  With  female  deer  the 
development  during  each  recurrent  season  of  great  branch- 
ing horns,  and  with  female  elephants  the  development  of 
immense  tusks  would  be  a  great  waste  of  vital  power,  sup- 
posing that  they  were  of  no  use  to  the  females.  Conse- 
quently they  would  have  tended  to  be  eliminated  in  the 
female  through  natural  selection;  that  is,  if  the  successive 
variations  were  limited  in  their  transmission  to  the  female 
sex,  for  otherwise  the  weapons  of  tlie  males  would  have 
been  injuriously  affected,  and  this  would  have  been  a  greater 
evil.  On  the  whole,  and  from  the  consideration  of  the  fol- 
lowing facts,  it  seems  probable  that  when  the  various 
weapons  differ  in  the  two  sexes  this  has  generally  depended 
on  the  kind  of  transmission  which  has  prevailed. 

As  the  reindeer  is  the  one  species  in  the  whole  family  of 
deer  in  which  the  female  is  furnished  with  horns,  though 
they  are  somewhat  smaller,  thinner  and  less  branched  than 
in  the  male,  it  might  naturally  be  thought  that  at  least,  in 
this  case,  they  must  be  of  some  special  service  to  her.  The 
female  retains  her  horns  from  the  time  when  they  are  fully 
developed,  namely,  in  September,  throughout  the  winter 

*  Owen  on  the  cachalot  and  Ornitliorhynchus,  ibid,  vol.  iii,  pp. 
G.38,  641.  Harting  is  quoted  by  Dr.  Zouteveen  in  the  Dutch  translat. 
ot  this  work,  vol.  ii,  p.  292. 


574  THE  DESCENT  OF  MAN. 

until  April  or  May,  when  she  brings  forth  her  young.  Mr. 
Crotch  made  particular  inquiries  for  me  in  Norway,  and  it 
appears  that  the  females  at  this  season  conceal  themselves 
for  about  a  fortnight  in  order  to  bring  forth  their  young, 
and  then  reappear  generally  hornless.  In  Nova  Scotia, 
however,  as  I  hear  from  Mr.  H.  Reeks,  the  female  some- 
times retains  her  horns  longer.  The  male,  on  the  other 
hand,  casts  his  horns  much  earlier,  toward  the  end  of 
November.  As  both  sexes  have  the  same  requirements  and 
follow  the  same  habits  of  life,  and  as  the  male  is  destitute 
of  horns  during  the  winter,  it  is  improbable  that  they  can 
be  of  any  special  service  to  the  female  during  this  season, 
which  includes  the  larger  part  of  the  time  during  which 
she  is  horned.  Nor  is  it  probable  that  she  can  have 
inherited  horns  from  some  ancient  progenitor  of  the  family 
of  deer,  for,  from  the  fact  of  the  females  of  so  many  species 
in  all  quarters  of  the  globe  not  having  horns,  we  may  con- 
clude that  this  was  the  primordial  character  of  the  group.* 
The  horns  of  the  reindeer  are  developed  at  a  most 
unusually  early  age;  but  what  the  cause  of  this  may  be  is 
not  known.  The  eifect  has  apparently  been  the  transfer- 
ence of  the  horns  to  both  sexes.  We  should  bear  in  mind 
that  horns  are  always  transmitted  through  the  female,  and 
that  she  has  a  latent  capacity  for  their  development,  as  we 
see  in  old  or  diseased  females,  f  Moreover,  the  females  of 
some  other  species  of  deer  exhibit  either  normally  or  occa- 
sionally rudiments  of  horns;  thus  the  female  of  Cervulus 
Dioschatus  has  ''  bristly  tufts,  ending  in  a  knob  instead  of 
a  horn;'"  and  *^^in  most  specimens  of  the  female  wapiti 
( Cervus  canadensis)  there  is  a  sharp,  bony  protuberance  in 
the  place  of   the  horn. '"J     From  these  several  considera- 

*0n  the  structure  and  shedding  of  the  horns  of  the  reindeer, 
Hoifberg,  "  Amoenitates  Acad.,"  vol.  iv,  1788,  p.  149.  See  Richard- 
son, "Fauna  Bor.  Americana,"  p.  241,  in  regard  to  the  American 
variety  or  species;  also  Maj.  W.  Ross  King,  "  The  Sportsman  in 
Canada,'  1866,  p.  80. 

•[Isidore  Qeoffroy  St.  Hilaire,  "Essais  de  Zoolog.  Generale,"  1841, 
p.  513.  Other  masculine  characters  besides  the  horns,  are  sometimes 
similarly  transferred  to  the  female;  thus  Mr.  Boner,  in  speaking  of 
an  old  female  chamois  ("Chamois  Hunting  in  the  Mountains  of 
Bavaria,"  1860,  2nd  edit.,  p.  363)  says,  "not  only  was  the  head  very 
male-looking,  but  along  the  back  there  was  a  ridge  of  long  hair, 
usually  to  be  found  only  in  bucks." 

I  On  the  Cervulus,  Dr.  Gray,   "Catalogue  of  Mammalia  in  the 


MAMMALS.  575 

tions  we  may  conclude  that  the  possession  of  fairly,  well- 
developed  horns  by  the  female  reindeer  is  due  to  the  males 
having  first  acquired  them  as  weapons  for  fighting  with 
other  males;  and  secondarily  to  their  development  from 
some  unknown  cause  at  an  unusually  early  age  in  the  males 
and  their  consequent  transference  to  both  sexes. 

Turning  to  the  sheath-horned  ruminants:  with  ante- 
lopes a  graduated  series  can  be  formed,  beginning  with 
species,  the  females  of  which  are  completely  destitute  of 
horns — passing  on  to  those  which  have  horns  so  small  as  to 
be  almost  rudimentary  (as  with  the  Antilocapra  americana, 
in  which  species  they  are  present  in  only  one  out  of  four 
or  five  females*) — to  those  which  have  fairly  developed 
horns,  but  manifestly  smaller  and  thinner  than  in  the 
male  and  sometimes  of  a  different  shapef — and  ending 
with  those  in  whicli  both  sexes  have  horns  of  equal  size. 
As  with  the  reindeer,  so  with  antelopes,  there  exists,  as 
previously  shown,  a  relation  between  the  period  of  the  devel- 
opment of  the  horns  and  their  transmission  to  one  or  both 
sexes;  it  is  therefore  probable  that  their  presence  or  ab- 
sence in  the  females  of  some  species  and  their  more  or  less 
perfect  condition  in  the  females  of  other  species  depends, 
not  on  their  being  of  any  special  use,  but  simply  in  inherit- 
ance. It  accords  with  this  view  that  even  in  the  same 
restricted  genus  both  sexes  of  some  species,  and  the  males 
alone  of  others,  are  thus  provided.  It  is  also  a  remarkable 
fact  that,  although  the  females  of  Antilope  hezoartica  are 
normally  destitute  of  horns,  Mr.  Blyth  has  seen  no  less 
than  three  females  thus  furnished;  and  there  was  no  reason 
to  suppose  that  they  were  old  or  diseased. 

In  all  the  wild  species  of  goats  and  sheep  the  horns  are 
larger  in  the  male  than  in  the  female,  and  are  sometimes 
quite  absent  in  the  latter.  J  In  several  domestic  breeds  of 
these   two   animals,  the  males   alone   are   furnished   with 

British  Maseum,"  part  iii,  p.  220.  On  the  Cervus  canadensis  or 
wapiti,  see  Hon.  J.  D.  Caton,  "Ottawa  Acad,  of  Nat.  Sciences,"  May, 
1868,  p.  9. 

*  I  am  indebted  to  Dr.  Canfield  for  this  information;  see  also  his 
paper  in  "  Proc.  Zoolog.  Soc,"  1866,  p.  105. 

+  For  instance,  the  horns  of  the  female  Ant.  eneJtore  resemble  those 
of  a  distinct  species,  viz.,  the  A7it.  dorcas  var.  Gorine,  see  Desmarest, 
**  Mammalogie,"  p.  455. 

JGray,  "Catalogue  Mamm.  Brit.  Mus.,"  part  iii,  1852,  p.  160. 


576  THE  DESCENT  OF  MAN. 

horns;  and  in  some  breeds,  for  instance,  in  the  sheep  of 
North  Wales,  though  both  sexes  are  properly  horned,  tlie 
ewes  are  very  liable  to  be  hornless.  I  have  been  informed 
by  a  trustworthy  witness,  who  purposely  inspected  a  flock 
of  these  same  sheep  during  the  lambing  season,  that  the 
horns  at  birth  are  generally  more  fully  developed  in  the  male 
than  in  the  female.  Mr.  ,^.  Peel  crossed  his  Lonk  sheep, 
both  sexes  of  which  always  bear  horns,  with  hornless  Lei- 
cesters  and  hornless  Shropshire  Downs;  and  the  result  was 
that  the  male  offspring  had  their  horns  considerably 
reduced,  while  the  females  were  wholly  destitute  of  them. 
These  several  facts  indicate  that,  with  sheep,  the  horns  are 
a  much  less  firmly  fixed  character  in  the  females  than  in  the 
males;  and  this  leads  us  to  look  at  the  horns  as  properly  of 
masculine  origin. 

With  the  adult  musk-ox  ( Ovibos  moschatus)  the  horns 
of  the  male  are  larger  than  those  of  the  female,  and  in  the 
latter  the  bases  do  not  touch.**  In  regard  to  ordinary 
cattle  Mr.  Blyth  remarks:  ''  In  most  of  the  wild  bovine 
animals  the  horns  are  both  longer  and  thicker  in  the  bull 
than  in  the  cow,  and  in  the  cowbanteng  {Bos  sondaicus) 
the  horns  are  remarkably  small,  and  inclined  much  back- 
ward. In  the  domestic  races  of  catte,  both  of  the  humped 
and  humpless  types,  the  horns  are  short  and  thick  in  the 
bull,  longer  and  more  slender  in  the  cow  and  ox;  and  in 
the  Indian  buffalo,  they  are  shorter  and  thicker  in  the  bull, 
longer  and  more  slender  in  the  cow.  In  the  wild  gaour  {B. 
gaurus)  the  horns  are  mostly  both  longer  and  thicker  in 
the  bull  than  in  the  cow.^'f  I^^'-  Forsyth  Major  also 
informs  me  that  a  fossil  skull,  believed  to  be  that  of  the 
female  Bos  estruscus,  has  been  found  in  Val  d^Arno, 
which  is  wholly  without  horns.  In  the  RMnoceros  simus, 
as  I  may  add,  the  horns  of  the  female  are  generally  longer 
but  less  powerful  than  in  the  male;  and  in  some  other 
species  of  rhinoceros  they  are  said  to  be  shorter  in  the 
female.  %  From  these  various  facts  we  may  infer  as  probable 
that  horns  of  all  kinds,  even  when  they  are  equally  devel- 
oped in  the  two  sexes,  were  primarily  acquired  by  the  male 

*  Richardson,  "  Fauna  Bor.  Americana,"  p.  278. 
f  "  Land  and  Water,"  1867,  p.  346. 

^Sir  Andrew   Smith,   "Zoology   of    S.   Africa,"   pi.    xix.     Owen, 
"  Anatomy  of  Vertebrates,"  vol.  iii,  p.  624. 


MAMMALS.  577 

in  order  to  conquer  other  males,  and  have  been  transferred 
more  or  less  completely  to  the  female. 

The  effects  of  castration  deserve  notice,  as  throwing  light  on 
this  same  point.  Stags  after  the  operation  never  renew  their 
horns.  The  male  reindeer,  however,  must  be  excepted,  as 
after  castration  he  does  renew  them.  This  fact,  as  well  as 
the  possession  of  horns  by  both  sexes,  seems  at  first  to  prove 
that  the  horns  in  this  species  do  not  constitute  a  sexual 
character;  *  but  as  they  are  developed  at  a  very  early  age, 
before  the  sexes  differ  in  constitution,  it  is  not  surprising 
that  they  should  be  unaffected  by  castration,  even  if  they 
were  aboriginally  acquired  by  the  male.  With  sheep 
both  sexes  properly  bear  horns ;  and  I  am  informed 
that  with  Welsh  sheep  the  horns  of  the  males  are  con- 
siderably reduced  by  castration ;  but  the  degree  depends 
much  on  the  age  at  which  the  operation  is  performed,  as 
is  likewise  the  case  with  other  animals.  Merino  rams  have 
large  horns,  while  the  ewes,  '*^  generally  speaking,  are  with- 
out horns;"  and  in  this  breed  castration  seems  to  produce 
a  somewhat  greater  effect,  so  that  if  performed  at  an  early 
age  the  horns  "  remain  almost  undeveloped. "f  On  the 
Guinea  coast  there  is  a  breed  in  which  the  females  never 
bear  horns,  and,  as  Mr.  Winwood  Reade  informs  me,  the 
rams  after  castration  are  quite  destitute  of  them.  With 
cattle  the  horns  of  the  males  are  much  altered  by  castration; 
for,  instead  of  being  short  and  thick,  they  become  longer 
than  those  of  the  cow,  but  otherwise  resemble  them.  The 
Antilope  hezoartica  offers  a  somewhat  analogous  case;  the 
males  have  long  straight  spiral  horns  nearly  parallel  to  each 
other,  and  directed  backward;  the  females  occasionally  bear 
horns,  but  these  when  present  are  of  a  very  different  shape, 
for  they  are  not  spiral,  and  spreading  widely  bend  round 
with  the  points  forward.  Now  it  is  a  remarkable  fact  that 
in  the  castrated  male,  as  Mr.  Blyth  informs  me,  the  horns 
are  of  the  same  peculiar  shape  as  in  the  female,  but  longer 

*This  is  the  conclusion  of  Seidlitz,  "Die  Darwinsche  Theorie," 
1871,  p.  47. 

f  I  am  much  obliged  to  Prof.  Victor  Cams  for  having  made  in- 
quiries for  me  in  Saxony  on  this  subject.  H.  von  Xathusius 
("  Viehzucht,"  1872,  p.  64)  says  that  the  horns  of  sheep  castrated  at 
an  early  period,  either  altogether  disappear  or  remain  as  mere  rudi- 
ments; but  I  do  not  know  whether  he  refers  to  merinos  or  to  ordinary 
breeds. 


578  THE  DESCENT  OF  MAN. 

and  thicker.  If  we  may  judge  from  analogy,  the  female 
probably  shows  us  in  these  two  cases  of  cattle  and  the 
antelope  the  former  condition  of  the  horns  in  some  early 
progenitor  of  each  species.  But  why  castration  should  lead 
to  the  reappearance  of  an  early  condition  of  the  lioriis 
cannot  be  explained  witli  any  certainty.  Nevertheless,  it 
seems  probable,  that  in  nearly  the  same  manner  as  the  con- 
stitutional disturbance  in  the  offspring,  caused  by  a  cross 
between  two  distinct  species  or  races,  often  leads  to  tlie 
reappearance  of  long-lost  characters;*  so  here  the  disturb- 
ance in  the  constitution  of  the  individual,  resulting  from 
castration,  produces  the  same  effect. 

The  tusks  of  the  elephant  in  the  different  species  or  races 
differ  according  to  sex,  nearly  as  do  the  horns  of  ruminants. 
In  India  and  Malacca  the  males  alone  are  provided  with 
well-developed  tusks.  The  elephant  of  Ceylon  is  con- 
sidered by  most  naturalists  as  a  distinct  race,  but  by  some 
as  a  distinct  species,  and  here  *^  not  one  in  a  hundred  is 
found  with  tusks,  the  few  that  possess  them  being  exclu- 
sively males."!  The  African  elephant  is  undoubtedly  dis- 
tinct, and  the  female  has  large  well-developed  tusks, 
though  not  so  large  as  those  of  the  male. 

These  differences  in  the  tusks  of  the  several  races  and 
species  of  elephants — the  great  variability  of  the  horns  of 
deer,  as  notably  in  the  wild  reindeer — the  occasional  presence 
of  horns  in  the  female  Antilope  Bezoarhca  and  their  frequent 
absence  in  the  female  of  Ajitilocapra  americana — the  pres- 
ence of  two  tusks  in  some  few  male  narwhals — the  complete 
absence  of  tusks  in  some  female  walruses — are  all  instances 
of  the  extreme  variability  of  secondary  sexual  characters, 
and  of  their  liability  to  differ  in  closely  allied  forms. 

Although  tusks  and  horns  appear  in  all  cases  to  have 
been  primarily  developed  as  sexual  weapons,  they  often 
serve  other  purposes.  The  elephant  uses  his  tusks  in 
attacking  the  tiger;  according  to  Bruce,  he  scores  the 
trunks  of  trees  until  they  can  be  thrown  down  easily,  and 
he  likewise  thus  extracts  the  farinaceous  cores  of  palms;  in 

*I  have  given  various  experiments  and  other  evidence  proving 
that  this  is  the  case,  in  my  "  Variation  of  Animals  and  Plants  under 
Domestication,"  vol.  ii,  1868,  pp.  39-47. 

fSir  J.  Emerson  Tennent,  "Ceylon,"  1859,  vol.  ii,  p.  274.  For 
Malacca,  "Journal  of  Indian  Archipelago,"  vol.  iv,  p.  357. 


MAMMALS,  579 

Africa  he  often  uses  one  tusk,  always  the  same,  to  probe 
the  ground  and  thus  ascertain  whether  it  will  bear  his 
weight.  The  common  bull  defends  the  herd  with  his 
horns;  and  the  elk  in  Sweden  has  been  known,  according 
to  Lloyd,  to  strike  a  wolf  dead  with  a  single  blow  of  his 
great  horns.  Many  similar  facts  could  be  given.  One  of 
the  most  curious  secondary  uses  to  which  the  horns  of  an 
animal  may  be  occasionally  put  is  that  observed  by  Capt. 
Hutton  *.with  the  wild  goat  {Capra  mgagrus)  of  the  Hima- 
layas and,  as  it  is  also  said  with  the  ibex,  namely,  that 
when  the  male  accidentally  falls  from  a  height  he  bends 
inward  his  head,  and,  by  alighting  on  his  massive  horns, 
breaks  the  shock.  The  female  cannot  thus  use  her  horns, 
which  are  smaller,  but  from  her  more  quiet  disposition  she 
does  not  need  this  strange  kind  of  shield  so  much. 

Each  male  animal  uses  his  weapons  in  his  own  peculiar 
fashion.  The  common  ram  makes  a  charge  and  butts  with 
such  force  with  the  bases  of  his  horns  that  I  have  seen  a 
powerful  man  knocked  over  like  a  child.  Goats  and  cer- 
tain species  of  sheep,  for  instance  the  Ovis  cydoceros  of 
Afghanistan,!  rear  on  their  hind  legs,  and  then  not  only 
butt,  but  *^  make  a  cut  down  and  a  jerk  up,  with  the  ribbed 
front  of  their  cimeter-shaped  horn,  as  with  a  saber.  When 
the  0.  cyclocerus  attacked  a  large  domestic  ram,  who  was  a 
noted  bruiser,  he  conquered  him  by  the  sheer  novelty  of 
his  mode  of  fighting,  always  closing  at  once  with  his 
adversary,  and  catching  him  across  the  face  and  nose  with 
a  sharp,  drawing  jerk  of  the  head,  and  then  bounding  out 
of  the  way  before  the  blow  could  be  returned.^'  In  Pem- 
brokeshire a  male  goat,  the  master  of  a  flock  which  during 
several  generations  had  run  wild,  was  known  to  have  killed 
several  males  in  single  combat;  this  goat  possessed  enormous 
horns,  measuring  thirty-nine  inches  in  a  straight  line  from 
tip  to  tip.  The  common  bull,  as  every  one  knows,  gores 
and  tosses  his  opponent;  but  the  Italian  buffalo  is  said 
never  to  use  his  horns;  he  gives  a  tremendous  blow  with 
his  convex  forehead,  and  then  tramples  on  his  fallen  enemy 
with  his  knees — an  instinct  which  the  common  bull  does 

*  "Calcutta  Journal  of  Nat.  Hist.,"  vol.  ii,  1843,  p.  526. 

tMr.  Blyth,  in  "Land  and  Water,"  March,  1867,  p.  134,  on  the 
authority  of  Capt.  Hutton  and  others.  For  the  wild  Pembrokeshire 
goats,  see  the  "Field,"  1869,  p.  150, 


580  THE  DESCENT  OF  MAN. 

not  possess.*  Hence,  a  dog  who  pins  a  buffalo  by  the  nose 
is  immediately  crushed.  We  must,  however,  remember 
that  the  Italian  buffalo  has  been  long  domesticated,  and  it 
is  by  no  means  certain  that  the  wild  parent-form  had  simi- 
lar horns.  Mr.  Bartlett  informs  me  that  when  a  female 
Cape  buffalo  {Bubalus  caffer)  was  turned  into  an  inclosure 
with  a  bull  of  the  same  species  she  attacked  him,  and  he  in 
return  pushed  her  about  with  great  violence.  But  it  was 
manifest  to  Mr.  Bartlett  that,  had  not  the  bull  shown 
dignified  forbearance,  he  could  easily  have  killed  her  by  a 
single  lateral  thrust  with  his  immense  horns.  The  giraffe 
uses  his  short,  hair  covered  horns,  which  are  rather  longer 
in  the  male  than  in  the  female,  in  a  curious  manner;  for. 


Fig.  63.    Oryx  leucoryx,  male  (from  the  Knowsley  Menagerie). 

with  his  long  neck,  he  swings  his  head  to  either  side, 
almost  upside  down,  with  such  force  that  I  have  seen 
a  hard  plank  deeply  indented  by  a  single  blow. 

With  antelopes  it  is  sometimes  difficult  to  imagine  how 
they  can  possibly  use  their  curiously  shaped  horns  ;  thus 
the  springboc  (Ant.  eucUore)  has  rather  short  upright 
horns,  with  the  sharp  points  bent  inward,  almost  at  right 
angles,  so  as  to  face  each  other  ;  Mr.  Bartlett  does  not 
know  how  they  are  used,  but  suggests  that  they  would 
inflict  a  fearful  wound  down  each  side  of  the  face  of  an 
antagonist.  The  slightly  curved  horns  of  the  Oryx  leu- 
coryx  (fig.  63)   are   directed   backward,  and   are  of  such 

*M.  E.  M,  Baillv,  "  Sur  I'usage  des  Comes,"  etc.,  "  Annal  des  Sc. 
Nat.,"  torn,  ii,  1824,  p.  369. 


MAMMALS.  581 

length  that  their  points  reach  beyond  the  middle  of  the 
back,  over  which  they  extend  in  almost  parallel  lines. 
Thus  they  seem  singularly  ill-fitted  for  fighting ;  but 
Mr.  Bartlett  informs  me  that  when  two  of  these  animals 
preprare  for  battle  they  kneel  down,  with  their  heads 
between  their  fore  legs,  and  in  this  attitude  the  horns 
stand  nearly  parallel  and  close  to  the  ground,  with  the 
points  directed  forward  and  a  little  upward.  The  combat- 
ants then  gradually  approach  each  other,  and  each  endeav- 
ors to  get  the  upturned  points  under  the  body  of  the  other; 
if  one  succeeds  in  doing  this,  he  suddenly  springs  up, 
throwing  up  his  head  at  the  same  time,  and  can  thus 
wound  or  perhaps  even  transfix  his  antagonist.  Both  ani- 
mals always  kneel  down,  so  as  to  guard  as  far  as  possible 
against  this  maneuver.  It  has  been  recorded  that  one  of 
these  antelopes  has  used  his  horns  with  effect  even  against 
a  lion;  yet,  from  being  forced  to  place  his  head  between 
the  fore  legs  in  order  to  bring  the  points  of  the  horns  for- 
ward, he  would  generally  be  under  a  great  disadvantage 
when  attacked  by  any  other  animal.  It  is,  therefore,  not 
probable  that  the  horns  have  been  modified  into  their 
present  great  length  and  peculiar  position  as  a  protection 
against  beasts  of  prey.  We  can,  however,  see  that  as  soon 
as  some  ancient  male  progenitor  of  the  Oryx  acquired  mod- 
erately long  horns,  directed  a  little  backward,  he  would  be 
compelled,  in  his  battles  with  rival  males,  to  bend  his  head 
somewhat  inward  or  downward,  as  is  now  done  by  certain 
stags;  and  it  is  not  improbable  that  he  might  have  acquired 
the  habit  of  at  first  occasionally  and  afterward  of  regularly 
kneeling  down.  In  this  case  it  is  almost  certain  that  the 
males  which  possessed  the  longest  horns  would  have  had  a 
great  advantage  over  others  with  shorter  horns;  and  then 
the  horns  would  gradually  have  been  rendered  longer 
and  longer,  through  sexual  selection,  until  they  acquired 
their  present  extraordinary  length  and  position. 

With  stags  of  many  kinds  the  branches  of  the  horns 
offer  a  curious  case  of  difficulty,  for  certainly  a  single 
straight  point  would  inflict  a  much  more  serious  wound 
than  several  diverging  ones.  In  Sir  Philip  Egerton's 
museum  there  is  a  horn  of  the  red  deer  {Cervus  elaphus) 
thirty  inches  in  length  with  '^  not  fewer  than  fifteen  snags 
or  branches;"  and  at  Moritzburg  there  is  still  preserved  a 
pair  of  antlers  of  a  red  deer,  shot  in  1699  by  Frederick  I, 


582  ^^^  DESCENT  OP  MAN. 

one  of  which  bears  the  astonishing  number  of  thirty-three 
branches  and  the  other  twenty-seven,  making  altogether 
sixty  branches.  Richardson  figures  a  pair  of  antlers  of 
the  wild  reindeer  with  twenty-nine  points.*  From  the 
manner  in  which  the  horns  are  branched,  and  more  espe- 
cially from  deer  being  known  occasionally  to  fight  together 
by  kicking  with  their  fore  feet,f  M.  Bailly  actually  comes 
to  the  conclusion  that  their  horns  are  more  injurious  than 
useful  to  them.  But  this  author  overlooks  the  pitched 
battles  between  rival  males.  As  I  felt  much  perplexed  about 
the  use  or  advantage  of  the  branches  I  applied  to  Mr. 
McNeill,  of  Colonsay,  who  has  long  and  carefully  observed 
the  habits  of  the  red  deer,  and  he  informs  me  that  he  has 
never  seen  some  of  the  branches  brought  into  use,  but  that 
the  brow  antlers  from  inclining  downward  are  a  great  pro- 
tection to  the  forehead,  and  their  points  are  likewise  used 
in  attack.  Sir  Philip  Egerton  also  informs  me  both  as  to 
red  deer  and  fallow  deer  that  in  fighting  they  suddenly 
dash  together,  and,  getting  their  horns  fixed  against  each 
other^s  bodies,  a  desperate  struggle  ensues.  When  one  is 
at  last  forced  to  yield  and  turn  round  the  victor  endeavors 
to  plunge  his  brow  antlers  into  his  defeated  foe.  It  thus 
appears  that  the  upper  branches  are  used  chiefly  or  exclu- 
sively for  pushing  and  fencing.  Nevertheless,  in  some 
species  the  upper  branches  are  used  as  weapons  of  offense; 
when  a  man  was  attacked  by  a  wapiti  deer  ( Cervus  cana- 
densis) in  Judge  Caton's  park  in  Ottawa  and  several  men 
tried  to  rescue  him  the  stag  "  never  raised  his  head  from 
the  ground;  in  fact,  he  kept  his  face  almost  flat  on  the 
ground,  with  his  nose  nearly  between  his  fore  feet,  except 
when  he  rolled  his  head  to  one  side  to  take  a  new  observa- 
tion preparatory  to  a  plunge. '^  In  this  position  the  ends 
of  the  horns  were  directed  against  his  adversaries.  "  In 
rolling  his  head  he  necessarily  raised  it  somewhat,  because 

*0n  the  horns  of  the  red  deer,  Owen,  "British  Fossil  Mammals," 
1846,  p.  478;  Richardson  on  the  horns  of  the  reindeer,  "Fauna  Bor. 
Americana,"  1829,  p.  240.  I  am  indebted  to  Prof.  Victor  Cams  for 
the  Moritzburg  case. 

fHon.  J.  D.  Caton  ("Ottawa  Acad,  of  Nat.  Science,"  May,  1868, 
p.  9)  says  that  the  American  deer  fight  with  their  fore  feet,  after 
"the  question  of  superiority  has  been  once  settled  and  acknowledged 
in  the  herd."  Bailly  "  Sur  I'usage  des  Cornes,"  "  Annales  des  So. 
Nat.,"  torn,  ii,  1824,  p.  371. 


MAMMALS, 


683 


his  antlers  were  so  long  that  he  could  not  roll  his  head 
without  raising  them  on  one  side,  while  on  the  other  they 
touched  the  ground."  The  stag  by  this  procedure  gradu- 
ally drove  the  party  of  rescuers   backward  to  a  distance 


Fig.  64.    Strepsiceros  Kudu  (from  Sir  Andrew  Smith's  "  Zoology  of 
South  Africa  "). 

of  one  hundred  and  fifty  or  two  hundred  feet,  and  the 
attacked  man  was  killed.* 

*  See  a  most  interesting  account  in  the  appendix  to  Hon.  J.  D. 
Caton's  paper,  as  above  quoted. 


584  't'HE  DESCENT  OP  MAN. 

Although  the  horns  of  stags  are  efficient  weapons,  there 
can,  I  think,  be  no  doubt  that  a  single  point  would 
have  been  much  more  dangerous  than  a  branched  antler; 
and  Judge  Caton,  who  has  had  large  experience  with  deer, 
fully  concurs  in  this  conclusion.  Nor  do  the  branching 
horns,  though  highly  important  as  a  means  of  defense 
against  rival  stags,  appear  perfectly  well  adapted  for  this 
purpose,  as  they  are  liable  to  become  interlocked.  The  sus- 
picion has,  therefore,  crossed  my  mind  that  they  may  serve 
m  part  as  ornaments.  That  the  branched  antlers  of  stags 
as  well  as  the  elegant  lyrated  horns  of  certain  antelopes, 
with  their  graceful  double  curvature  (fig.  64),  are  orna- 
mental in  our  eyes,  no  one  will  dispute.  If,  then,  the 
horns,  like  the  splendid  accouterments  of  the  knights  of 
old,  add  to  the  noble  appearance  of  stags  and  antelopes, 
they  may  have  been  modified  partly  for  this  purpose,  though 
mainly  for  actual  service  in  battle;  but  I  have  no  evidence 
in  favor  of  this  belief. 

An  interesting  case  has  lately  been  published,  from  which 
it  appears  that  the  horns  of  a  deer  in  one  district  in 
the  United  States  are  now  being  modified  through  sexual 
and  natural  selection.  A  writer  in  an  excellent  American 
journal  *  says  that  he  has  hunted  for  the  last  twenty-one 
years  in  the  Adirondacks,  where  the  Cervus  virginianus 
abounds.  About  fourteen  years  ago  he  first  heard  of  spike- 
Jiorn,  hucks.  These  became  from  year  to  year  more 
common;  about  five  years  ago  he  shot  one,  and  afterward 
another,  and  now  they  are  frequently  killed.  ^^  The  spike- 
horn  differs  greatly  from  the  common  antler  of  the  C.  vir- 
ginianus. It  consists  of  a  single  spike,  more  slender  than 
the  antler,  and.  scarcely  half  so  long,  projecting  forward 
from  the  brow  and  terminating  in  a  very  sharp  point.  It 
gives  a  considerable  advantage  to  its  possessor  over  the 
common  buck.  Besides  enabling  him  to  run  more  swiftly 
through  the  thick  woods  and  underbrush  (every  hunter 
knows  that  does  and  yearling  bucks  run  much  more  rapidly 
than  the  large  bucks  when  armed  with  their  cumbrous 
antlers),  the  spike-horn  is  a  more  effective  weapon  than  the 
common  antler.  With  this  advantage  the  spike  -  horn 
bucks  are  gaining  upon  the  common  bucks,  and  may,  in 
time,  entirely  supersede  them  in  the  Adirondacks.     Un- 

*"  The  American  Naturalist,"  Dec,  1869,  p.  553. 


MAMMALS.  585 

doubtedly,  the  first  spike-hom  buck  was  merely  an  acci- 
dental freak  of  nature.  But  his  spike-horns  gave  him  an 
advantage,  and  enabled  him  to  propagate  his  peculiarity. 
His  descendants,  having  a  like  advantage,  have  propagated 
the  peculiarity  in  a  constantly  increasing  ratio,  till  they  are 
slowly  crowding  the  antlered  deer  from  the  region  they 
inhabit.^'  A  critic  has  well  objected  to  this  account  by 
asking,  why,  if  the  simple  horns  are  now  so  advantageous, 
were  the  branched  antlers  of  the  parent-form  ever  devel- 
oped? To  this  I  can  only  answer  by  remarking  that  a  new 
mode  of  attack  with  new  weapons  might  be  a  great  advant- 
age, as  shown  by  the  case  of  the  Ovis  cycloceros,  who  thus 
conquered  a  domestic  ram  famous  for  his  fighting  power. 
Though  the  branched  antlers  of  a  stag  are  well  adapted  for 
fighting  with  his  rivals,  and,  though  it  might  be  an 
advantage  to  the  prong-horned  variety  slowly  to  acquire 
long  and  branched  horns,  if  he  had  to  fight  only  with 
others  of  the  same  kind,  yet  it  by  no  means  follows  that 
branched  horns  would  be  the  best  fitted  for  conquering  a 
foe  differently  armed.  In  the  foregoing  case  of  the  Oryx 
leucoryx  it  is  almost  certain  that  the  victory  would  rest 
with  an  antelope  having  short  horns,  and  who,  therefore, 
did  not  need  to  kneel  down,  though  an  oryx  might  profit 
by  having  still  longer  horns  if  he  fought  only  with  his 
proper  rivals. 

Male  quadrupeds,  which  are  furnished  with  tusks,  use 
them  in  various  ways,  as  in  the  case  of  horns.  The  boar 
strikes  laterally  and  upward ;  the  musk-deer  downward 
with  serious  effect.*  The  walrus,  though  having  so  short 
a  neck  and  so  unwieldly  a  body,  '^  can  strike  either  upward 
or  downward  or  sideways  with  equal  dexterity,  "f  I  was 
informed  by  the  late  Dr.  Falconer,  that  the  Indian  elephant 
fights  in  a  different  manner  according  to  the  position  and 
curvature  of  his  tusks.  When  they  are  directed  forward 
and  upward  he  is  able  to  fling  a  tiger  to  a  great  distance — 
it  is  said  to  even  thirty  feet;  when  they  are  short  and 
turned  doVnward  he  endeavors  suddenly  to  pin  the  tiger  to 
the  ground,  and,  in  consequence,  is  dangerous  to  the  rider, 
who  is  liable  to  be  jerked  oft'  the  howdali.J 

♦Pallas,  "  Spicilegia  Zoologica,"  fasc.  xiii,  1779,  p.  18. 

f  Lamont,  "  Seasons  with  the  Sea-Horses,"  1861,  p.  141. 

^See  also  Corse  ("  Philosopli.  Transact.,"  1799,  p.    212)  on  the 


586  THE  DESCENT  OF  MAN. 

Very  few  male  quadrupeds  possess  weapons  of  two  dis- 
tinct kinds  specially  adapted  for  fighting  with  rival  males. 
The  male  muntjac-deer  (Cervulus),  however,  offers  an  ex- 
ception, as  he  is  provided  with  horns,  and  exserted  canine 
teeth.  But  we  may  infer  from  what  follows  that  one  form 
of  weapon  has  often  been  replaced  in  the  course  of  ages  by 
another.  With  ruminants  the  development  of  horns  gen- 
erally stands  in  an  inverse  relation  with  that  of  even  mod- 
erately developed  canine  teeth.  Tlius  camels,  guanacoes, 
chevro tains  and  musk-deer  are  hornless,  and  they  have 
efficient  canines;  these  teeth  being  ^'  always  of  smaller  size 
in  the  females  than  in  the  males. ''^  The  Camelidae  have, 
in  addition  to  their  true  canines,  a  pair  of  canine-shaped  in- 
cisors in  their  upper  jaws.*  Male  deer  and  antelopes,  on 
the  other  hand,  possess  horns,  and  they  rarely  have  canine 
teeth;  and  these,  when  present,  are  always  of  small  size,  so 
that  it  is  doubtful  whether  they  are  of  any  service  in  their 
battles.  In  Antilope  montana  they  exist  only  as  rudiments 
in  the  young  male,  disappearing  as  he  grows  old;  and  they 
are  absent  in  the  female  at  all  ages;  but  the  females  of  cer- 
tain other  antelopes  and  of  certain  deer  have  been  known 
occasionally  to  exhibit  rudiments  of  these  teeth,  f  Stallions 
have  small  canine  teeth,  which  are  either  quite  absent  or 
rudimentary  in  the  mare;  but  they  do  not  appear  to  be  used 
in  fighting,  for  stallions  bite  with  their  incisors,  and  do 
not  open  their  mouths  wide  like  camels  and  guanacoes. 
Whenever  the  adult  male  possesses  canines,  now  inefficient, 
while  the  female  has  either  none  or  mere  rudiments,  we 
may  conclude  that  the  early  male  progenitor  of  the  species 
was  provided  with  efficient  canines,  which  have  been  par- 
tially transferred  to  the  females.  The  reduction  of  these 
teeth  in  the  males  seems  to  have  followed  from  some  change 

manner  in  which  the  short-tusked  Mooknah  variety  attacks  other 
elephants. 

*Owen,  "  Anatomy  of  Vertebrates,"  vol.  iii,  p.  349. 

f  See  Ruppell  (in  "  Proc,  Zooloff.  Soc,"  Jan.  12,  1836,  *p.  3)  on  the 
canines  in  deer  and  antelopes,  with  a  note  by  Mr.  Martin  on  a  female 
American  deer.  See  also  Falconer  (**  Palaeont.  Memoirs  and  Notes," 
vol.  i,  1868,  p,  576)  on  canines  in  an  adult  female  deer.  In  old  males 
of  the  musk-deer  the  canines  (Pballas,  "  Spic.  Zoolog.,"  fasc  xiii, 
1779,  p.  18)  sometimes  grow  to  tlie  length  of  three  inches,  while  in 
old  females  a  rudiment  projects  scarcely  half  an  inch  above  the 
gums. 


MAMMALS.  587 

in  their  manner  of  fighting,  often  (but  not  in  the  horse) 
caused  by  the  development  of  new  weapons. 

Tusks  and  horns  are  manifestly  of  high  importance  to 
their  possessors,  for  their  development  consumes  much 
organized  matter.  A  single  tusk  of  the  Asiatic  elephant — 
one  of  the  extinct  woolly  species — and  of  the  African  ele- 
phant have  been  known  to  weigh  respectively  one  hundred 
and  fifty,  one  hundred  and  sixty  and  one  hundred  and 
eighty  pounds;  and  even  greater  weights  have  been  given 
by  some  authors.  *  With  deer,  in  which  the  horns  are  peri- 
odically renewed,  the  drain  on  the  constitution  must  be 
greater;  the  horns,  for  instance,  of  the  moose  weigh  from 
fifty  to  sixty  pounds,  and  those  of  the  extinct  Irish  elk 
from  sixty  to  seventy  pounds  —  the  skull  of  the  latter 
weighing  on  an  average  only  five  pounds  and  a  quarter. 
Although  the  horns  are  not  periodically  renewed  in  sheep, 
yet  their  development,  in  the  opinion  of  many  agricultur- 
ists, entails  a  sensible  loss  to  the  breeder.  Stags,  more- 
over, in  escaping  from  beasts  of  prey  are  loaded  with  an 
additional  weight  for  the  race,  and  are  greatly  retarded  in 
passing  through  a  woody  country.  The  moose,  for  in- 
stance, with  horns  extending  five  and  a  half  feet  from  tip 
to  tip,  although  so  skillful  in  their  use  that  he  will  not 
touch  or  break  a  twig  when  walking  quietly,  cannot  act  so 
dexterously  while  rushing  away  from  a  pack  of  wolves. 
^'  During  his  progress  he  holds  his  nose  up  so  as  to  lay  the 
horns  horizontally  back;  and  in  this  attitude  cannot  see 
the  ground  distinctly."}  The  tips  of  the  horns  of  the 
great  Irish  elk  were  actually  eight  feet  apart!  While  the 
horns  are  covered  with  velvet,  which  lasts  with  red  deer 
for  about  twelve  weeks,  they  are  extremely  sensitive  to  a 
blow;  so  that  in  Germany  the  stags  at  this  time  somewhat 
change  their  habits,  and,  avoiding  dense  forests,  frequent 
young  woods  and  low  thickets.  |  These  facts  remind  us 
that  male  birds  have  acquired  ornamental  plumes  at  the 

♦Emerson  Tennent,  "Ceylon,"  1859,  vol.  ii,  p.  275;  Owen, 
"  British  Fossil  Mammals,"  1846.  p.  245. 

f  Richardson,  "Fauna  Bor.  Americana,"  on  the  moose.  Alces  pcU- 
mata,  pp.  236,  237;  on  the  expanse  of  the  horns,  "  Land  and  Water," 
1869.  p.  143.  See  also  Owen,  "British  Fossil  Mammals,"  on  the 
Irish  elk,  pp.  447,  455. 

X  "  Forest  Creatures,"  by  C.  Boner,  1861,  p.  60. 


588  THE  DESCENT  OF  MAN. 

cost  of  retarded  fliglit,  and  other  ornaments  at  the  cost  of 
some  loss  of  power  in  their  battles  with  rival  males. 

With  mammals,  when,  as  is  often  the  case,  the  sexes 
differ  in  size,  the  males  are  almost  always  larger  and 
stronger.  I  am  informed  by  Mr.  Gould  that  this  holds 
good  in  a  marked  manner  with  the  marsupials  of  Aus- 
tralia, the  males  of  which  appear  to  continue  growing 
until  an  unusually  late  age.  But  the  most  extraordinay, 
case  is  that  of  one  of  the  seals  (Callorhinus  ursinurs) 
a  full-grown  female  weighing  less  than  one-sixth  of  a  full- 
gi'own  male.*  Dr.  Gill  remarks  that  it  is  with  the  polyg- 
amous seals,  the  males  of  which  are  well  known  to  fight 
savagely  together,  that  the  sexes  diifer  much  in  size;  the 
monogamous  species  differing  but  little.  Whales  also 
afford  evidence  of  the  relation  existing  between  the  pug- 
nacity of  the  males  and  their  large  size  compared  with  that 
of  the  females;  the  males  of  the  right- whales  do  not  fight 
together,  and  they  are  not  larger,  but  rather  smaller,  than 
their  females;  on  the  other  hand,  male  sperm-whales  fight 
much  together,  and  their  bodies  are  ^^  often  found  scarred 
with  the  imprint  of  their  rivaFs  teeth,"  and  they  are 
double  the  size  of  the  females.  Tlie  greater  strength  of 
the  male,  as  Hunter  long  ago  remarked,  f  is  invariably  dis- 
played in  those  parts  of  the  body  which  are  brought  into 
action  in  fighting  with  rival  males — for  instance,  in  the 
massive  neck  of  the  bull.  Male  quadrupeds  are  also  more 
courageous  and  pugnacious  than  the  females.  There  can  be 
little  doubt  that  these  characters  have  been  gained,  partly 
through  sexual  selection,  owing  to  a  long  series  of  victo- 
ries, by  the  stronger  and  more  courageous  males  over  the 
weaker,  and  partly  through  the  inherited  effects  of  use. 
It  is  probable  that  the  successive  variations  in  strength, 
size,  and  courage,  whether  due  to  mere  variability  or  to  the 
effects  of  use,  by  the  accumulation  of  which  male  quadru- 
peds have  acquired  these  characteristic  qualities,  occurred 
rather  late  in  life,  and  were  consequently  to  a  large  extent 
limited  in  their  transmission  to  the  same  sex. 

*See  the  very  interesting  paper  by  Mr.  J.  A.  Allen  in  "Bull.  Mus. 
Comp.  Zoolog.  of  Cambridge,  United  States,"  vol.  ii,  No.  1,  p.  82. 
The  weights  were  ascertained  by  a  careful  observer,  Capt,  Bryant. 
Dr.  Gill  in  "  The  American  Naturalist,"  Jan.,  1871;  Prof.  Shaler  on 
the  relative  size  of  the  sexes  of  whales,  ''American  Naturalist," 
Jan.  1873. 

f  •'  Animal  Economy,"  p.  45 


MAMMALS.  589 

From  these  considerations  I  was  anxious  to  obtain  infor- 
mation as  to  the  Scotch  deer-hound,  the  sexes  of  which 
differ  more  in  size  than  those  of  any  other  breed  (though 
blood-hounds  differ  considerably),  or  than  in  any  wild 
canine  species  known  to  me.  Accordingly,  I  applied  to 
Mr.  Oupples,  well  known  for  his  success  with  this  breed, 
w^ho  has  weighed  and  measured  many  of  his  own  dogs,  and 
who  has  with  great  kindness  collected  for  me  the  following 
facts  from  various  sources.  Fine  male  dogs,  measured  at 
the  shoulder,  range  from  28  inches,  which  is  low,  to  33  or 
even  34  inches  in  height ;  and  in  weight  from  80  pounds, 
which  is  light,  to  120  pounds,  or  even  more.  The 
females  range  in  height  from  23  to  27,  or  even 
to  28  inches ;  and  in  weight  from  50  to  70, 
or  even  80  pounds.*  Mr.  Cupples  concludes  that  from 
95  to  100  pounds  for  the  male,  and  70  for  the  female, 
would  be  a  safe  average;  but  there  is  reason  to  believe  that 
formerly  both  sexes  attained  a  greater  weight.  Mr.  Cup- 
ples has  weighed  puppies  when  a  fortnight  old;  in  one 
litter  the  average  weight  of  four  males  exceeded  that  of 
two  females  by  six  and  a  half  ounces;  in  another  litter  the 
average  weight  of  four  males  exceeded  that  of  one  female 
by  less  than  one  ounce;  the  same  males  when  three  weeks 
old  exceeded  the  females  by  seven  and  a  half  ounces,  and 
at  the  age  of  six  weeks  by  nearly  fourteen  ounces.  Mr. 
Wright,  of  Yeldersley  House,  in  a  letter  to  Mr.  Oupples 
says:  ^^I  have  taken  notes  on  the  sizes  and  weights  of 
puppies  of  many  litters,  and,  as  far  as  my  experience  goes, 
dog  puppies,  as  a  rule,  differ  very  little  from  bitches  till 
they  arrive  at  about  five  or  six  months  old;  and  then  the 
dogs  begin  to  increase,  gaining  upon  the  bitches  both  in 
weight  and  size.  At  birth  and  for  several  weeks  afterward 
a  bitch-puppy  will  occasionally  be  larger  than  any  of  the 
dogs,  but  they  are  invariably  beaten  by  them  later."  Mr. 
McNeill,  of  Colonsay,  concludes  that  "  the  males  do  not 
attain  their  full  growth  till  over  two  years  old,  though  the 
females   attain   it   sooner."     According  to   Mr.    Oupples' 

*  See  also  Richardson's  "  Manual  on  the  Dog,"  p.  59.  Much  valu- 
able information  on  the  Scottish  deer  hound  is  given  by  Mr.  Mc- 
Neill, who  first  called  attention  to  the  inequality  in  size  between  the 
sexes,  in  Scrope's  "  Art  of  Deer  Stalking."  I  hope  that  Mr.  Cupples 
will  keep  to  his  intention  of  publishing  a  full  account  and  history  of 
this  famous  breed. 


590  THE  DESCENT  OF  MAN, 

experience,  male  dogs  go  on  growing  in  stature  till  they 
are  from  twelve  to  eighteen  months  old,  and  in  weight  till 
from  eighteen  to  twenty-four  months  old;  while  the  females 
cease  increasing  in  stature  at  the  age  of  from  nine  to  four- 
teen or  fifteen  months,  and  in  weight  at  the  age  of  from 
twelve  to  fifteen  months.  From  these  various  statements 
it  is  clear  that  the  full  difference  in  size  between  the  male 
and  female  Scotch  deer-hound  is  not  acquired  until  rather 
late  in  life.     The  males  almost  exclusively  are  used  for 

coursing,  for,  as  Mr.  Mc- 
Neill informs  me,  the  fe- 
males have  not  sufficient 
strength  and  weight  to 
pull  down  a  full-grown 
deer.  From  the  names 
used  in  old  legends  it 
appears,  as  I  hear  from 
Mr.  Cupples,  that  at  a 
very  ancient  period  the 
males  were  the  most 
celebrated,  the  females 
being  mentioned  only  as 
.     ,  the  mothers   of   famous 

Fiff.  65,     Head  of  comm(  n  wild  boar,  m   ^ „  tt^.,^„        ^„„,-„^ 

prime  of  life  (from  Brehm).  dogS.  Heuce,      durmg 

many  generations  it  is  the 
male  which  has  been  chiefly  tested  for  strength,  size,  speed 
and  courage,  and  the  best  will  have  been  bred  from.  As, 
however,  the  males  do  not  attain  their  full  dimensions  until 
rather  late  in  life  they  will  have  tended,  in  accordance 
with  the  law  often  indicated,  to  transmit  their  characters 
to  their  male  off'spring  alone;  and  thus  the  great  inequality 
in  size  between  the  sexes  of  the  Scotch  deer-hound  may 
probably  be  accounted  for. 

The  males  of  some  few  quadrupeds  possess  organs  or 
parts  developed  solely  as  a  means  of  defense  against  the 
attacks  of  other  males.  Some  kinds  of  deer  use,  as  we 
have  seen,  the  upper  branches  of  their  horns  chiefly  or 
exclusively  for  defending  themselves;  and  the  Oryx  ante- 
lope, as  I  am  informed  by  Mr.  Bartlett,  fences  most  skill- 
fully with  his  long,  gently  curved  horns ;  but  these  are 
likewise  used  as  organs  of  offense.  The  same  observer 
remarks  that  rhinoceroses  in  fighting  parry  each  other's 
sidelong  blows  with  their  horns,  which   clatter  loudly 


MAMMALS.  591 

together,  as  do  the  tusks  of  boars.  Although  wild  boars 
figlit  desperately,  they  seldom,  according  to  Brehm,  receive 
fatal  wounds,  as  the  blows  fall  on  each  other's  tusks,  or  on 
the  layer  of  gristly  skin  covering  the  shoulder,  called  by 
the  German  hunters  the  shield;  and  here  we  have  a  part 
specially  modified  for  defense.  With  boars  in  the  prime 
of  life  (fig.  65)  the  tusks  in  the  lower  jaw  are  used  for 
fighting,  but  they  become  in  old  age,  as  Brehm  states,  so 


Fig.  66.    Skull  of  the  Babirusa  Pig  (from  Wallace's  "  Malay  Archipelago"). 

much  curved  inward  and  upward  over  the  snout  that  they 
can  no  longer  be  used  in  this  way.  They  may,  however, 
still  serve,  and  even  more  effectively,  as  a  means  of  defense. 
In  compensation  for  the  loss  of  the  lower  tusks  as  weapons 
of  offense  those  in  the  upper  jaw,  which  always  project  a 
little  laterally,  increase  in  old  age  so  much  in  length  and 
curve  so  much  upward  that  they  can  be  used  for  attack. 
Nevertheless,  an  old  boar  is  not  so  dangerous  to  man  as 
one  at  the  age  of  six  or  seven  years.* 

^  *5fPlwa,  "  Tbierleben,"  B.  ii,  ss.  729-73^.  ' 


592  THE  DESCENT  OF  MAN. 

In  the  full-grown  male  Babirusa  pig  of  Celebes  (fig.  66), 
the  lower  tusks  are  formidable  weapons,  like  those  of  the 
European  boar  in  the  prime  of  life,  while  the  upper  tusks 
are  so  long  and  have  their  points  so  much  curled  inward, 
sometimes  even  touching  the  forehead,  that  they  are  utterly 
useless  as  weapons  of  attack.  They  more  nearly  resemble 
horns  than  teeth,  and  are  so  manifestly  useless  as  teeth  that 
the  animal  was  formerly  supposed  to  rest  his  head  by  hook- 
ing them  on  to  a  branch!  Their  convex  surfaces,  however, 
if  the  head  were  held  a  little  laterally,  would  serve  as  an 


FifT.  67.  Head  of  female  -Ethiopian  wart-hofr,  from  "  Proc.  Zool.  Soc."  1869, 
showing  the  same  characters  as  the  male,  though  on  a  reduced  scale. 

N.  B.  When  the  engraving  was  first  made  I  was  under  the  impression  that  it 
represented  the  male. 

excellent  guard;  and  hence,  perhaps,  it  is  that  in  old 
animals  they  ^'  are  generally  broken  off,  as  if  by  fighting."* 
Here,  then,  we  have  the  curious  case  of  the  upper  tusks  of 
the  Babirusa  regularly  assuming  during  the  prime  of  life  a 
structure  which  apparently  renders  them  fitted  only  for 
defense  ;  while  in  the  European  boar  the  lower  tusks 
assume  in  a  less  degree  and  only  during  old  age  nearly  the 
same  form,  and  then  serve  in  like  manner  solely  for 
defense. 
In  the  wart-hog  ( Phacochoerus   cBtliiopicus)  (fig.  67)  the 

*See  Mr.  Wallace's  interesting  account  of  this  animal,    "The 
Mala^  Archipelago,"  1969,  vol.  i,  p.  435. 


MAMMALS.  593 

tusks  in  the  upper  jaw  of  the  male  curve  upward  during 
the  prime  of  life,  and  from  being  pointed  serve  as  formid- 
able weapons.  Tlie  tusks  in  the  lower  jaw  are  sharper 
tlian  those  in  the  upper,  but  from  their  shortness  it  seems 
hardly  possible  tliat  they  can  be  used  as  weapons  of  attack. 
They  must,  however,  greatly  strengthen  those  in  tlie  upper 
jaw,  from  being  ground  so  as  to  fit  closely  against  their 
bases.  Neither  the  upper  nor  the  lower  tusks  appear  to 
have  been  specially  modified  to  act  as  guards,  though  no 
doubt  they  are  to  a  certain  extent  used  for  this  purpose. 
But  the  wart-hog  is  not  destitute  of  other  special  means 
of  protection,  for  it  has  on  each  side  of  the  face, 
beneath  the  eyes,  a  rather  stiff,  yet  flexible  cartilaginous 
oblong  pad  (see  fig. 67),  which  projects  two  or  three  inches 
outward;  and  it  appeared  to  Mr.  Bartlett  and  myself, 
when  viewing  the  living  animal,  that  these  pads,  when 
struck  from  beneath  by  the  tusks  of  an  opponent,  would 
be  turned  upward,  and  would  thus  admirably  protect 
the  somewhat  prominent  eyes.  I  may  add,  on  the 
authority  of  Mr.  Bartlett,  that  these  boars  when  fight- 
ing stand  directly  face  to  face. 

Lastly,  the  African  river-hog  {PofomocJweriis  penicil- 
latus) has  a  hard  cartilaginous  knob  on  each  side  of  the 
face  beneath  the  eyes,  which  answers  to  the  flexible  pad 
of  the  wart-hog;  it  has  also  two  bony  prominences  on  the 
upper  jaw  above  the  nostrils.  A  boar  of  this  species  in 
the  Zoological  Gardens  recently  broke  into  the  cage  of 
the  wart-hog.  They  fought  all  night  long,  and  were 
found  in  the  morning  much  exhausted,  but  not  seriously 
w^ounded.  It  is  a  significant  fact,  as  showing  the  purposes 
of  the  above  described  projections  and  excrescences,  that 
these  were  covered  with  blood,  and  were  scored  and  abraded 
in  an  extraordinary  manner. 

Although  the  males  of  so  many  members  of  the  pig 
family  are  provided  with  weapons,  and,  as  we  have  just  seen, 
with  means  of  defense,  these  weapons  seem  to  have  been 
acquired  within  a  rather  late  geological  period.  Dr.  For- 
syth Major  specifies*  several  miocene  species,  in  none  of 
which  do  the  tusks  appear  to  have  been  largely  developed 
in  the  males;  and  Prof.  Riitimeyer  was  formerly  struck 
with  this  same  fact. 

*"  Atti  dellft  Soc,  Italiana  di  Sc.  Nat."  1873,  vol,  xv,  fasc.  iv. 


594  THE  DESCENT  OF  MAN. 

The  niatle  of  the  Hon  forms  a  good  defense  against  the 
attacks  of  rival  lions^  the  One  danger  to  which  he  is  liable; 
for  the  males>  as  Sir  A.  Smith  intonnS  nie^  engage  in  ter- 
rible battles,  and  a  yOimg  lion  dares  not  approach  an 
old  one.  In  1857  a  tiger  at  Bromwich  broke  into  the  cage 
of  a  lion  and  a  fearful  scene  ensued;  ^^tlie  lion's  mane 
saved  his  neck  and  head  from  being  much  injured,  but  the 
tiger  at  last  succeeded  in  ripping  up  his  belly,  and  in  a  few 
minutes  he  was  dead."  *  The  broad  ruff  round  the  throat 
and  chin  of  the  Canadian  lynx  {Felis  canadensis)  is  much 
longer  in  the  male  than  in  the  female;  but  whetlier  it 
serves  as  a  defense  I  do  not  know.  Male  seals  are  well 
known  to  fight  desperately  together,  and  the  males  of  cer- 
tain kinds  ( Otaria  juhata)  \  have  great  manes,  while  the 
females  have  small  ones  or  none.  The  male  baboon  of 
the  Cape  of  Good  Hope  {Cynocephalus  porcarius)  has  a 
much  longer  mane  and  larger  canine  teeth  than  the  female; 
and  the  mane  probably  serves  as  a  protection,  for,  on 
asking  the  keepers  in  the  Zoological  Gardens,  without 
giving  them  any  clew  to  my  object,  whether  any  of  the 
monkeys  especially  attacked  each  other  by  the  nape  of  the 
neck,  I  was  answered  that  this  was  not  the  case,  except 
with  the  above  baboon.  In  the  Hamadryas  baboon, 
Ehrenber^  compares  the  mane  of  the  adult  male  to  that  of 
a  young  lion,  while  in  the  young  of  both  sexes  and  in  the 
female  the  mane  is  almost  absent. 

It  appeared  to  me  probable  that  the  immense  woolly 
mane  of  the  male  American  bison,  which  reaches  almost  to 
the  ground,  and  is  much  more  developed  in  the  males  than 
in  the  females,  served  as  a  protection  to  them  in  their  ter- 
rible battles;  but  an  experienced  hunter  told  Judge  Caton 
that  he  had  never  observed  anything  which  favored  this 
belief.  The  stallion  has  a  thicker  and  fuller  mane  than 
the  mare;  and  I  have  made  particular  inquiries  of  two  great 
trainers  and  breeders,  who  have  had  charge  of  many 
entire    horses,    and    am    assured   that   they    ''  invariably 

*  "  The  Times,"  Nov.  10,  1857.  In  regard  to  the  Canada  lynx,  see 
Audubon  and  Bachman,  "Quadrupeds  of  North  America,"  1846,  p. 
139. 

fDr.  Murie,  on  Otaria,  "  Proc.  Zoolog.  Soc,"  1869,  p.  109.  Mr. 
J.  A.  Allen,  in  the  paper  above  quoted  (p.  75),  doubts  whether  the 
hair,  which  is  longer  on  the  neck  in  the  male  than  in  the  female, 
deserves  to  be  called  a  mane. 


MAMMALS,  695 

endeavor  to  seize  one  another  by  the  neck/'  It  does  not, 
however,  :tpllow  from  the  foregoing  statements,  that  when 
the  hair  on  the  neck  serves  as  a  defense,  ^that  it  wa«  origi- 
nally developed  for  this  purpose,  though  this  is  probable  in 
some  cases,  as  in  that  of  the  lion.  I  am  informed  by  Mr. 
McNeill  that  the  long  hairs  on  the  throat  of  the  stag 
( Cervus  elaphus)  serve  as  a  great  protection  to  him  when 
hunted,  for  the  dogs  generally  endeavor  to  seize  him  by  the 
throat;  but  it  is  not  probable  that  these  hairs  were  specially 
developed  for  this  purpose;  otherwise  the  young  and  the 
females  would  have  been  equally  protected. 

Choice  in  Pairing  hy  Either  Sex  of  Qiiadriipeds. — Before 
describing,  in  the  next  chapter,  the  differences  between  the 
sexes  in  voice,  odors  emitted  and  ornaments,  it  will  be  con- 
venient here  to  consider  whether  the  sexes  exert  any  choice 
in  their  unions.  Does  the  female  prefer  any  particular 
male,  either  before  or  after  the  males  may  have  fought 
together  for  supremacy;  or  does  the  male,  when  not  a 
polygamist,  select  any  particular  female?  The  general 
impression  among  breeders  seems  to  be  that  the  male  accepts 
any  female;  and  this,  owing  to  his  eagerness,  is,  in  most 
cases,  probably  the  truth.  Whether  the  female,  as  a 
general  rule,  indifferently  accepts  any  male  is  much  more 
doubtful.  In  the  fourteenth  chapter,  on  birds,  a  consider- 
able body  of  direct  and  indirect  evidence  was  advanced 
showing  that  the  female  selects  her  partner;  and  it  would 
be  a  strange  anomaly  if  female  quadrupeds,  which  stand 
higher  in  the  scale  and  have  higher  mental  powers,  did  not 
generally,  or  at  least  often,  exert  some  choice.  The  female 
could  in  most  cases  escape,  if  wooed  by  a  male  that  did  not 
please  or  excite  her;  and  when  pursued  by  several  males, 
as  commonly  occurs,  she  would  often  have  the  opportunity, 
while  they  were  fighting  together,  of  escaping  with  some 
one  male,  or  at  least  of  temporarily  pairing  with  him. 
This  latter  contingency  has  often  been  observed  in  Scot- 
land with  female  red  deer,  as  I  am  informed  by  Sir  Philip 
Egerton  and  others.* 

*  Mr.  Boner,  in  bis  excellent  description  of  the  habits  of  tbe  red- 
deer  in  Germany  ("  Forest  Creatures,"  1861,  p.  81)  says,  '*  wbile  tbe 
stag  is  defending  bis  rigbts  against  one  intruder,  anotber  invades  tbe 
sanctuary  of  bis  barem,  and  carries  off  tropby  after  tropby." 
Exactly  the  same  thing  occurs  with  seals,  ^e  Mr.  J.  A.  Allen,  ibid, 
P.  100. 


I 
596  THE  DESCENT  OF  MAN. 

It  is  scarcely  possible  that  much  should  be  known  about 
female  quadrupeds  in  a  state  of  nature  making  any  choice 
in  their  marriage  unions.  The  following  curious  details 
on  the  courtship*  of  one  of  the  eared  seals  (Callorlnnus 
iirsimis)  are  given*  on  the  authority  of  Capt.  Bryant,  who 
liad  ample  opportunities  for  observation.  He  says:  *'  Many 
of  the  females  on  their  arrival  at  the  island  where  they 
breed  appear  desirous  of  returning  to  some  particular  male, 
and  frequently  climb  the  outlying  rocks  to  overlook  the 
rookeries,  calling  out  and  listening  as  if  for  a  familiar 
voice.  Then  changing  to  another  place  they  do  the  same 
again  ...  As  soon  as  a  female  reaches  the  shore,  the 
nearest  male  goes  down  to  meet  her,  making,  meanwhile, 
a  noise  like  the  clucking  of  a  hen  to  her  chickens.  He 
bows  to  her  and  coaxes  her  until  he  gets  between  her  and 
the  water  so  that  she  cannot  escape  him.  Then  his  man- 
ner changes  and  witii  a  harsh  growl  heflrives  her  to  a  place 
in  his  harem.  This  continues  until  the  lower  row  of 
liarems  is  nearly  full.  Then  the  males  higher  up  select 
the  time  when  their  more  fortunate  neighbors  are  off  their 
guard  to  steal  their  wives.  This  they  do  by  taking  them  in 
their  mouths  and  lifting  them  over  the  heads  of  the  other 
females  and  carefully  placing  them  in  their  own  harem, 
carrying  them  as  cats  do  their  kittens.  Those  still  higher 
up  pursue  the  same  method  until  the  whole  space  is  occu- 
pied. Frequently  a  struggle  ensues  between  two  males  for 
the  possession  of  the  same  female,  and  both  seizing  her  at 
once  pull  her  in  two  or  terribly  lacerate  her  with  their 
teeth.  When  the  space  is  all  filled,  the  old  male  walks 
around  complacently  reviewing  his  family,  scolding  those 
who  crowd  or  disturb  the  others  and  fiercely  driving  off  all 
intruders.  This  surveillance  always  keeps  him  actively 
occupied." 

As  so  little  is  known  about  the  courtship  of  animals  in  a 
state  of  nature,  I  have  endeavored  to  discover  how  far  our 
domesticated  quadrupeds  evince  any  choice  in  their  unions. 
Dogs  offer  the  best  opportunity  for  observation,  as  they 
are  carefully  attended  to  and  well  understood.  Many 
breeders  have  expressed  a  strong  opinion  on  this  head. 
Thus,   Mr.   May  hew  remarks:   ^'  The  females  are  able  to 

*Mr.  J.  A.  Allen  in  "Bull.  Mus.  Comp.  Zoolog.  of  Cambridge, 
United  States,"  vol.  ii,  No,  1,  p.  99. 


MAMMALS.  597 

bestow  their  affections ;  and  tender  recollections  are  as 
potent  over  them  as  they  are  known  to  be  in  other  cases, 
where  higher  animals  are  concerned.  Bitches  are  not 
always  prudent  in  their  loves,  but  are  apt  to  fling  them- 
selves away  on  curs  of  low  degree.  If  reared  with  a  com- 
panion of  vulgar  appearance,  there  often  springs  up  between 
the  pair  a  devotion  which  no  time  can  afterward  subdue. 
The  passion,  for  such  it  really  is,  becomes  of  a  more  than 
romantic  endurance."  Mr.  May  hew,  who  attended  chiefly 
to  the  smaller  breeds,  is  convinced  that  the  females  are 
strongly  attracted  by  males  of  a  large  size.*  The  well- 
known  veterinary  Blaine  statesf  that  his  own  female  pug 
became  so  attached  to  a  spaniel,  and  a  female  setter  to  a 
cur,  that  in  neither  case  would  they  pair  with  a  dog  of  their 
own  breed  until  several  weeks  had  elapsed.  Two  similar 
and  trustworthy  accounts  have  been  given  me  in  regard  to 
a  female  retriever  and  a  spaniel,  both  of  which  became 
enamoured  with  terrier  dogs. 

Mr.  Cupples  informs  me  that  he  can  personally  vouch 
for  the  accuracy  of  the  following  more  remarkable  case,  in 
which  a  valuable  and  wonderfully  intelligent  female  terrier 
loved  a  fetriever  belonging  to  a  neighbor  to  such  a  degree 
that  she  had  often  to  be  dragged  away  from  him.  After 
their  permanent  separation,  although  repeatedly  showing 
milk  in  her  teats,  she  would  never  acknowledge  the  court- 
ship of  any  other  dog,  and,  to  the  regret  of  her  owner,  never 
bore  puppies.  Mr.  Cupples  also  states  that,  in  1868,  a 
female  deerliound  in  his  kennel  thrice  produced  puppies, 
and  on  each  occasion  showed  a  marked  preference  for  one 
of  the  largest  and  handsomest,  but  not  the  most  eager,  of 
four  deerhounds  living  with  her,  all  in  the  prime  of  life. 
Mr.  Cupples  has  observed  that  the  female  generally  favors 
a  dog  whom  she  has  associated  with  and  knows;  her  shy- 
ness and  timidity  at  first  incline  her  against  a  strange  dog. 
The  male,  on  the  contrary,  seems  rather  inclined  toward 
strange  females.  It  appears  to  be  rare  when  the  male 
refuses  any  particular  female,  but  Mr.  Wright,  of  Yelders- 
ley  House,  a  great  breeder  of  dogs,  informs  me  that  he  has 
known  some  instances;  he  cites  the  case  of  one  of  his  own 

*"Dogs:  Their  Management,"  by  E.  Mayhew,  M.  R.  C.  V.  S., 
2d  edit.,  1864,  pp.  187-192. 

f  Quoted  by  Alex.  Walker,  "On  Intermarriage,"  1838,  p.  276;  see 
also  p.  244. 


598  THE  DESCENT  OF  MAN, 

deerhounds  who  would  not  take  any  notice  of  a  particular 
female  mastiff,  so  that  another  deerhound  had  to  be 
employed.  It  would  be  superfluous  to  give,  as  I  could, 
other  instances,  and  I  will  only  add  that  Mr.  Barr,  who 
has  carefully  bred  many  bloodhounds,  states  that  in  almost 
every  instance  particular  individuals  of  opposite  sexes  show 
a  decided  preference  for  each  other.  Finally,  Mr.  Cup- 
pies,  after  attending  to  this  subject  for  another  year,  has 
written  to  me:  "  I  have  had  full  confirmation  of  my  former 
statement  that  dogs  in  breeding  form  decided  preferences 
for  each  other,  being  often  influenced  by  size,  bright  color 
and  individual  characters,  as  well  as  by  the  degree  of  their 
previous  familiarity.^' 

In  regard  to  horses,  Mr.  Blenkiron,  the  greatest  breeder 
of  race-horses  in  the  world,  informs  me  that  stallions  are 
so  frequently  capricious  in  their  choice,  rejecting  one  mare 
and  without  any  apparent  cause  taking  to  another,  that 
various  artifices  have  to  be  habitually  used.  The  famous 
Monarque,  for  instance,  would  never  consciously  look  at  the 
dam  of  Gladiateur,  and  a  trick  had  to  be  practiced.  We 
can  partly  see  the  reason  why  valuable  race-horse  stallions, 
which  are  in  such  demand  as  to  be  exhausted,  shoilld  be  so 
particular  in  their  choice.  Mr.  Blenkiron  has  never  known 
a  mare  reject  a  horse  ;  but  this  has  occurred  in  Mr. 
Wright's  stable,  so  that  the  mare  had  to  be  cheated. 
Prosper  Lucas*  quotes  various  statements  from  French 
authorities,  and  remarks:  ^^On  voit  des  etalons  qui  s'epren- 
nent  d'une  jument,  et  negligent  toutes  les  autres.''  He 
gives,  on  the  authority  of  Baelen,  similar  facts  in  regard  to 
bulls;  and  Mr.  H.  Reeks  assures  me  that  a  famous  short- 
horn bull,  belonging  to  his  father,  ''^invariably  refused  to 
be  matched  with  a  black  cow."  Hoffberg,  in  describing 
the  domesticated  reindeer  of  Lapland,  says:  ^'FcBmin^e 
majores  et  fortiores  mares  prae  caeteris  admittunt,  ad  eos 
confugiunt,  a  junioribus  agitatae,  qui  hos  in  fugam  con- 
jiciunt."  t  A  clergyman,  who  has  bred  many  pigs,  asserts 
that  sows  often  reject  one  boar  and  immediately  accept 
another. 

From  these  facts  there  can  be  no  doubt  that,  with  most 
of  our  domesticated  quadrupeds,  strong  individual  antipa- 

*  "  Traite  de  I'Hered.  Nat.."  torn,  ii,  1850,  p.  296. 
t  "  AmoenitateB  Acad.,"  vol.  iv,  1788,  p.  160. 


MAMMALS,  599 

thies  and  preferences  are  frequently  exhibited,  and  much 
more  commonly  by  the  female  than  by  the  male.  This 
being  the  case,  it  is  improbable  that  the  unions  of  quadru- 
peds in  a  state  of  nature  should  be  left  to  mere  chance.  It 
is  much  more  probable  that  the  females  are  allured  or 
excited  by  particular  males  who  possess  certain  characters 
in  a  higher  degree  than  other  males;  but  what  these  char- 
acters are  we  can  seldom  or  never  discover  with  certainty. 


600  ^tlE  DESCENT  OF  MAN, 


CHAPTER    XVIII. 

SECONDARY   SEXUAL   CHARACTERS  OF   MAMMALS — 

continued. 

Voice  —  Remarkable  sexual  peculiarities  in  seals  —  Odor  —  Develop- 
ment of  the  hair — Color  of  the  hair  and  skin — Anomalous  case 
of  the  female  being  more  ornamented  than  the  male — Color  and 
ornaments  due  to  sexual  selection — Color  acquired  for  the  sake 
of  protection — Color,  though  common  to  both  sexes,  often  due  to 
sexual  selection — On  the  disappearance  of  spots  and  stripes  in 
adult  quadrupeds — On  the  colors  and  ornaments  of  the  quad- 
rumana — Summary. 

Quadrupeds  use  their  voices  for  various  purposes,  as  a 
signal  of  danger,  as  a  call  from  one  member  of  a  troop  to 
another,  or  from  the  mother  to  her  lost  offspring,  or  from 
the  latter  for  protection  to  their  mother;  but  such  uses 
need  not  here  be  considered.  We  are  concerned  only  with 
the  difference  between  the  voices  of  the  sexes;  for  instance, 
between  that  of  the  lion  and  lioness,  or  of  the  bull  and 
cow.  Almost  all  male  animals  use  their  voices  much  more 
during  the  rutting-season  than  at  any  other  time  ;  and 
some,  as  the  giraffe  and  porcupine,*  are  said  to  be  com- 
pletely mute  excepting  at  this  season.  As  the  throats  {i.e. 
of  the  larynx  and  thyroid  bodies  f)  of  stags  periodically 
become  enlarged  at  the  beginning  of  the  breeding-season, 
it  might  be  thought  that  their  powerful  voices  must  be 
somehow  of  high  importance  to  them;  but  this  is  very 
doubtful.  From  information  given  to  me  by  two  experi- 
enced observers,  Mr.  McNeill  and  Sir  P.  Egerton,  it  seems 
that  young  stags  under  three  years  old  do  not  roar  or 
bellow;  and  that  the  old  ones  begin  bellowing  at  the  com- 
mencement of  the  breeding-season,  at  first  only  occasionally 
and  moderately,  while  they  restlessly  wander  about  in 
search  of  the  females.     Their  battles  are  prefaced  by  loud 

*Owen,  "  Anatomy  of  Vertebrates,"  vol.  iii,  p.  585. 
t  Ibid,  p.  595. 


MAMMALS,  601 

and  prolonged  bellowing,  but  during  tlie  actual  conflict 
they  are  silent.  Animals  of  all  kinds  which  habitually  use 
their  voices  utter  various  noises  under  any  strong  emotion, 
as  when  enraged  and  preparing  to  fight ;  but  this  may 
merely  be  the  result  of  nervous  excitement,  which  leads  to 
the  spasmodic  contraction  of  almost  all  the  muscles  of  the 
body,  as  when  a  man  grinds  his  teeth  and  clenches  his  fists 
in  rage  or  agony.  No  doubt  stags  challenge  each  other  to 
mortal  combat  by  bellowing;  but  those  with  the  more 
powerful  voices,  unless  at  the  same  time  the  stronger,  better- 
armed  and  more  courageous,  would  not  gain  any  advantage 
over  their  rivals. 

It  is  possible  that  the  roaring  of  the  lion  may  be  of 
some  service  to  him  by  striking  terror  into  his  adversary;  for 
when  enraged  he  likewise  erects  his  mane  and  thus  instinct- 
ively tries  to  make  himself  appear  as  terrible  as  possible. 
But  it  can  hardly  be  supposed  that  the  bellowing  of  the 
stag,  even  if  it  be  of  service  to  him  in  this  way,  can  have 
been  important  enough  to  'have  led  to  the  periodical 
enlargement  of  the  throat.  Some  writers  suggest  that  the 
bellowing  serves  as  a  call  to  the  female;  but  the  expe- 
rienced observers  above  quoted  inform  me  that  female  deer 
do  not  search  for  the  male,  though  the  males  search 
eagerly  for  the  females,  as  indeed  might  be  expected  from 
what  we  know  of  the  habits  of  other  male  quadrupeds. 
The  voice  of  the  female,  on  the  other  hand,  quickly  brings 
to  her  one  or  more  stags,*  as  is  well  known  to  the  hunters 
who  in  wild  countries  imitate  her  cry.  If  we  could  believe 
that  the  male  had  the  power  to  excite  or  allure  the  female 
by  his  voice,  the  periodical  enlargement  of  his  vocal  organs 
would  be  intelligible  on  the  principle  of  sexual  selection, 
together  with  inheritance  limited  to  the  same  sex  and 
season;  but  we  have  no  evidence  in  favor  of  this  view. 
As  the  case  stands,  the  loud  voice  of  the  stag  during  the 
breeding-season  does  not  seem  to  be  of  any  special  service 
to  him,  either  during  his  courtship  or  battles,  or  in  any 
other  way.  But  may  we  not  believe  that  the  frequent  use 
of  the  voice,  under  the  strong  excitement  of  love,  jealousy 
and  rage,  continued  during  many  generations,  may  at  last 

*  See,  for  instance,  Maj.  W.  Ross  King  ("The  Sportsman  in 
Canada,"  1866,  pp.  53,  131)  on  the  habits  of  the  moose  and  wild 
reindeer. 


G02  'I'HK  J)E8GKNT  OF  MAN. 

have  produced  an  inherited  effect  on  the  vocal  organs  of 
tlie  stag  as  well  as  of  other  male  animals  ?  This  appears  to 
me,  in  our  present  state  of  Jinowledge,  tlie  most  probable 
view. 

The  voice  of  the  adult  male  gorilla  is  tremendous,  and 
he  is  furnished  with  a  laryngeal  sack,  as  is  the  adult  male 
orang.*  The  gibbons  rank  among  the  noisiest  of  monkeys, 
and  the  Sumatra  species  {Hylobates  syndactyltis)  are  also 
furnished  with  an  air  sack;  but  Mr.  Blyth,  who  has  had 
opportunities  for  observation,  does  not  believe  that  the  male 
is  noiser  than  the  female.  Hence,  these  latter  monkeys 
probably  use  their  voices  as  a  mutual  call ;  and  this  is  cer- 
tainly the  case  with  some  quadrupeds,  for  instance  the 
beaver,  t  Another  gibbon,  the  H.  agilis,  is  remarkable, 
from  having  the  power  of  giving  a  complete  and  correct 
octave  of  musical  notes,!  which  we  may  reasonably  suspect 
serves  as  a  sexual  charm;  but  I  shall  have  to  recur  to  this 
subject  in  the  next  chapter.  The  vocal  organs  of  the 
American  Mycetes  caraya  are  one-third  larger  in  the  male 
than  in  the  female,  and  are  wonderfully  powerful.  These 
monkeys  in  warm  weather  make  the  forests  resound  at 
morning  and  evening  with  their  overwhelming  voices. 
The  males  begin  the  dreadful  concert  and  often  continue 
it  during  many  hours,  the  females  sometimes  joining  in 
with  their  less-powerful  voices.  An  excellent  observer — 
Kengger§ — could  not  perceive  that  they  were  excited  to 
begin  by  any  special  cause  ;  he  thinks  that,  like  many 
birds,  they  delight  in  their  own  music,  and  try  to  excel  each 
other.  AVhether  most  of  the  foregoing  monkeys  have 
acquired  their  powerful  voices  in  order  to  beat  their  rivals 
and  cliarm  the  females — or  whether  the  vocal  organs  have 
been  strengthened  and  enlarged  through  the  inherited 
effects  of  long-continued  use  without  any  particular  good 
being  thus  gained — I  will  not  pretend  to  say;  but  the 
former  view,  at  least  in  the  case  of  the  Hylobates  agilis, 
seems  the  most  probable. 

*Owen,  "  Anatomy  of  Vertebrates,"  vol.  iii,  p.  600. 

f  Mr.  Green,  in  "  Journal  of  Linn.  Soc,"  vol.  x,  Zoology,  1869,  p. 
362. 

JC.  L.  Martin,  "  General  Introduction  to  the  Nat.  Hist,  of  Mamm. 
Animals,"  1841,  p.  431. 

§ "  Naturgeschichte  der  Siiugetbiere  von  Paraguay,"  1830,  ss. 
16,  21. 


MAMAfALS.  603 

I  may  here  mention  two  very  curious  sexual  peculiarities 
occurring  in  seals,  because  they  have  been  supposed  by 
some  writers  to  affect  the  voice.  Tlie  nose  of  the  male 
sea-elephant  {Macrorhinus  proboscideus)  becomes  greatly 
elongated  during  the  breeding-season  and  can  then  be 
erected.  In  this  state  it  is  sometimes  a  foot  in  length. 
The  female  is  not  thus  provided  at  any  period  of  life. 
The  male  makes  a  wild,  hoarse,  gurgling  noise,  which  is 
audible  at  a  great  distance  and  is  believed  to  be  strength- 
ened by  the  proboscis;  the  voice  of  the  female  being  differ- 
ent. Lesson  compares  the  erection  of  the  proboscis  with 
the  swelling  of  the  wattles  of  male  gallinaceous  birds 
while  courting  the  females.  In  another  allied  kind  of 
seal,  the  bladder-nose  (Cystophora  cristata),  the  head  is 
covered  by  a  great  hood  or  bladder.  This  is  supported  by 
the  septum  of  the  nose,  which  is  produced  far  backward 
and  rises  into  an  internal  crest  seven  inches  in  height. 
The  hood  is  clothed  with  short  hair  and  is  muscular;  it 
can  be  inflated  until  it  more  than  equals  the  whole  head  in 
size!  The  males  when  rutting  fight  furiously  on  the  ice, 
and  their  roaring  ''  is  said  to  be  sometimes  so  loud  as  to 
be  heard  four  miles  off.^'  AYhen  attacked  they  likewise 
roar  or  bellow ;  and  whenever  irritated  the  bladder  is 
inflated  and  quivers.  Some  naturalists  believe  that  the 
voice  is  thus  strengthened,  but  various  other  uses  have 
been  assigned  to  this  extraordinary  structure.  Mr.  R. 
Brown  thinks  that  it  serves  as  a  protection  against  acci- 
dents of  all  kinds;  but  this  is  not  probable,  for,  as  I  am 
assured  by  Mr.  Lament,  who  killed  six  hundred  of  these 
animals,  the  hood  is  rudimentary  in  the  females  and  it  is 
not  developed  in  the  males  during  youth.* 

Odor. — With  some  animals,  as  with  the  notorious  skunk 
of  America,  the  overwhelming  odor  which  they  emit 
appears  to  serve  exclusively  as  a  defense.  With  shrew- 
mice  (Sorex)  both  sexes  possess  abdominal  scent-glands, 

*0n  the  sea- elephant,  see  an  article  by  Lesson,  in  "Diet.  Class. 
Hist.  Nat.,"  torn,  xiii,  p.  418.  For  the  Cystophora,  or  Stemraatopus, 
see  Dr.  Dekay,  "Annals  of  Lyceum  of  Nat.  Hist.  New  York,"  vol. 
i,  1824,  p.  94.  Pennant  has  also  collected  information  from  the 
sealers  on  this  animal.  The  fullest  account  is  given  by  Mr.  Brown, 
in  "  Proc.  Zoolog.  Soc,"  1868,  p.  435. 


604  T^^  DESCENT  OF  MAN, 

and  there  can  "be  little  doubt,  from  the  rejection  of  their 
bodies  by  birds  and  beasts  of  prey,  that  the  odor  is  pro- 
tective; nevertheless,  the  glands  become  enlarged  in  the 
males  during  the  breeding-season.  In  many  other  quad- 
rupeds the  gUmds  are  of  the  same  size  in  both  sexes,*  but 
their  uses  are  not  known.  In  other  species  the  glands  are 
confined  to  the  males  or  are  more  developed  than  in  the 
females  ;  and  they  almost  always  become  more  active 
during  the  rutting-season.  At  this  period  the  glands  on 
the  sides  of  the  face  of  the  male  elephant  enlarge  and  emit 
a  secretion  having  a  strong  musky  odor.  The  males,  and 
rarely  the  females,  of  many  kinds  of  bats  have  glands  and 
protrudable  sacks  situated  in  various  parts;  and  it  is 
believed  that  these  are  odoriferous. 

The  rank  effluvium  of  the  male  goat  is  well  known,  and 
that  of  certain  male  deer  is  wonderfully  strong  and  per- 
sistent. On  the  banks  of  the  Plata  I  perceived  the  air 
tainted  with  the  odor  of  the  male  Cervus  campestris  at 
half  a  mile  to  leeward  of  a  herd;  and  a  silk  handkerchief, 
in  which  I  carried  home  a  skin,  though  often  used  and 
washed,  retained  when  first  unfolded  traces  of  the  odor  for 
one  year  and  seven  months.  This  animal  does  not  emit 
its  strong  odor  until  more  than  a  year  old,  and  if  castrated 
while  young  never  emits  it.f  Besides  the  general  odor 
permeating  the  whole  body  of  certain  ruminants  (for  in- 
stance. Bos  moschahis)  in  the  breeding-season,  many  deer, 
antelopes,  sheep  and  goats  possess  odoriferous  glands  in 
various  situations,  more  especially  on  their  faces.  The 
so-called  tear-sacks,  or  suborbital  pits,  come  under  this 
head.  These  glands  secrete  a  semi-fluid  fetid  matter  which 
is  sometimes  so  copious  as  to  stain  the  whole  face,  as  I 
have  myself  seen  in  an  antelope.  They  are  "usually 
larger  in  the  male  than  in  the  female,  and  their  develop- 

*As  with  tlie  castoreum  of  the  beaver,  see  Mr.  L.  H,  Morgan's 
most  interesting  work,  *'Tlie  American  Beaver,"  1868,  p.  300. 
Pallas  ("  Spic.  Zoolog.,"  fasc.  viii,  1779,  p.  23)  has  well  discussed  the 
odoriferous  glands  of  mammals.  Owen  ("Anat.  of  Vertebrates," 
vol.  iii,  p.  634)  also  gives  an  account  of  these  glands,  including  those 
of  the  elephant,  and  (p.  763)  those  of  shrew-mice.  On  bats,  Mr. 
Dobson  in  "  Proc.  Zoolog.  Soc,"  1873,  p.  241. 

f  Rengger,  "  Naturgeschichte  der  Saugethiere  von  Paraguay," 
1830,  s.  355.  This  observer  also  gives  some  curious  particulars  in 
regard  to  the  odor. 


MAMMALS.  605 

ment  is  checked  by  castration."*  According  to  Desmarest, 
they  are  altogether  absent  in  the  female  of  Antilope  sub- 
gutturosa.     Hence,  there  can  be  no  doubt  that  they  stand 
in  close  relation  with  the  reproductive  functions.     They 
are  also  sometimes  present,  and  sometimes  absent,  in  nearly 
allied  forms.     In  the  adult  male  musk  deer  {MoscUus  mtrs- 
chiferiis)  a  naked  space  round  the  tail  is  bedewed*  with  an 
odoriferous  fluid,  while  in  the  adult  female,  itftd'  in   the: 
male  until  two  years  old,  this  space  is  covered  with  hair 
and  is  not  odoriferous.      The  proper  musk-sack   of   this; 
deer  is  from  its  position  necessarily  confined  to  the  male 
and  forms  an  additional  scent-organ.     It  is  a  singular  faei. 
that  the  matter  secreted  by  this  latter  gland  does  not,, 
according  to  Pallas,  change  in  consistence  or  increase  in 
quantity    during    the   rutting  -  season ;   nevertheless,    this' 
naturalist  admits  that   its  presence  is  in  some  way  con- 
nected with  the  act  of  reproduction.     He  gives,  however, 
only  a  conjectural  and   unsatisfactory  explanation  of   its. 
use.  t 

In  most  cases,  when  only  the  male  emits  a  strong  odor 
during  the  breeding-season,  it  probably  serves  to  excite  or 
allur.e  the  female.  We  must  not  judge  on  this  head  by  our 
own  taste,  for  it  is  well  known  that  rats  are  enticed  by 
certain  essential  oils,  and  cats  by  valerian,  substances  far 
from  agreeable  to  us;  and  that  dogs,  though  they  will  not 
eat  carrion,  sniff  and  roll  on  it.  From  the  reasons  given 
when  discussing  the  voice  of  the  stag  we  may  reject  the 
idea  that  the  odor  serves  to  bring  the  females  from  a  dis- 
tance to  the  males.  Active  and  long-continued  use  cannot 
here  have  come  into  play,  as  in  the  case  of  the  vocal  organs. 
The  odor  emitted  must  be  of  considerable  importance  to 
the  male,  inasmuch  as  large  and  complex  glands,  furnished 
with  muscles  for  everting  the  sack  and  for  closing  or  open- 
ing the  orifice,  have  in  some  cases  been  developed.  The 
development  of  these  organs  is  intelligible  through  sexual 
selection  if  the  most  odoriferous  males  are  the  most  suc- 

*Owen,  "  Anatomy  of  Vertebrates,"  vol.  iii,  p.  632.  See  also  Dr. 
Murie's  observations  on  these  glands  in  the  "  Proc.  Zoolog.  Soc.," 
1870,  p.  340.  Desmarest,  on  the  Antilope  subgutturosa,  ' '  Mammal- 
ogie,"  1820.  p.  455. 

f  Phallas,  "  Spicilegia  Zoolog,,"  fasc.  xiii,  1799,  p.  24;  Desmou- 
lins,  "Diet,  Class.  4'I^t  Nat.,"  torn,  iii,  p.  586, 


606  THE  DESCENT  OF  MAN, 

cessful  in  winning  the  females,  and  in  leaving  offspring  to 
inherit  their  gradually  perfected  glands  and  colors. 

Developme7it  of  the  Hair. — We  have  seen  that  male  quad- 
rupeds often  have  the  hair  on  their  necks  and  slioulders 
much  more  developed  than  the  females;  and  many  addi- 
tional instances  could  be  given.  This  sometimes  serves  as 
a  defense  to  the  male  during  his  battles;  but  whetiier  the 
hair  in  most  cases  has  been  specially  developed  for  this 
purpose  is  very  doubtful.  We  may  feel  almost  certain  that 
this  is  not  the  case,  when  only  a  thin  and  narrow  crest  runs 
along  the  back  ;  for  a  crest  of  this  kind  would  afford 
scarcely  any  protection,  and  the  ridge  of  the  back  is  not 
a  place  likely  to  be  injured;  nevertheless  such  crests  are 
sometimes  confined  to  the  males,  or  are  much  more  devel- 
oped in  them  than  in  the  females.  Two  antelopes,  the 
Tragelaphus  scriptus"^  (see  fig.  70,  p.  620)  and  Portax  picta 
may  be  given  as  instances.  When  stags  and  the  males  of 
wild  goat  are  enraged  or  terrified  these  crests  stand  erect ;t 
but  it  cannot  be  supposed  that  they  have  been  developed 
merely  for  the  sake  of  exciting  fear  in  their  enemies.  One 
of  the  above-named  antelopes,  the  Partax  picta,  has  a  large, 
well-defined  brush  of  black  hair  on  the  throat,  and  this  is 
much  larger  in  the  male  than  in  the  female.  In  the 
Ammotragus  tragelaphics  of  N.  Africa,  a  member  of  the 
sheep  family,  the  fore  legs  are  almost  concealed  by  an 
extraordinary  growth  of  hair,  which  depends  from  the 
neck  and  upper  halves  of  the  legs;  but  Mr.  Bartlett  does 
not  believe  that  this  mantle  is  of  the  least  use  to  the  male, 
in  whom  it  is  much  more  developed  than  in  the  female. 

Male  quadrupeds  of  many  kinds  differ  from  the  females 
in  having  more  hair,  or  hair  of  a  dift'erent  character,  on 
certain  parts  of  their  faces.  Thus  the  bull  alone  has  curled 
hair  on  the  forehead.  X  In  three  closely  allied  sub-genera 
of  the  goat  family  only  the  males  possess  beards,  sometimes 
of  large  size;  in  two  other  sub-genera  both  sexes  have  a 

*  Dr.  Gray,  "  Gleanings  from  the  Menagerie  at  Knowsley,"  pi.  28. 

f  Judge  Caton  on  the  Wapiti,  "Transact.  Ottawa  Acad.  Nat. 
Sciences,"  1868,  pp.  36,  40;  Blyth,  "  Land  and  Water,"  on  Capra 
cegagrus,  1867,  p.  37. 

X  '*  Hunter's  Essays  and  Observations,"  edited  by  Owen,  1861,  vol. 
i,  p.  236. 


MAMMALS, 


607 


beard,  but  it  disappears  in  some  of  the  domestic  breeds  of 
the  common  goat;  and  neither  sex  of  the  Hemitragus  has 
a  beard.  In  the  ibex  the  beard  is  not  developed  during  the 
summer,  and  it  is  so  small  at  other  times  that  it  may  be 
called  rudimentary.*  With  some  monkeys  the  beard  is 
confined  to  the  male,  as  in  the  orang;  or  is  much  larger  in 


i?o 


Ilg,  68.    Pithecia  satanas,  male  (from  Brehm). 


the  male  than  in  the  female,  as  in  the  Mycetes  caraya  and 
Pithecia  sanatas  (fig.  68).  So  it  is  with  the  whiskers  of 
some  species  of  Macaous,t  and,  as  we  have  seen,  with  the 
manes  of  some  species  of  baboons.  But  with  most  kinds 
of  monkeys  the  various  tufts  of  hair  about  the  face  and 
head  are  alike  in  both  sexes. 

*See  Dr.  Gray's  "Cat.  of  Mammalia  in  British  Museum,"  part  iii, 
1852,  p.  144. 

fRengger,  "Saugethiere,"  etc.,  s.  14;  Desmarest,  "Mammal- 
ogie,"  p.  86. 


608  THE  DESCENT  OF  MAN, 

The  males  of  various  members  of  the  ox  family  (Bovidae), 
and  of  certain  antelopes,  are  furnished  with  a  dewlap  or 
great  fold  of  skin  on  the  neck,  which  is  much  less  devel- 
oped in  the  female. 

Now,  what  must  we  conclude  with  respect  to  such  sexual 
differences  as  these?  No  one  will  pretend  that  the  beards 
of  certain  male  goats,  or  the  dewlap  of  the  bull,  or  the 
crests  of  hair  along  the  backs  of  certain  male  antelopes, 
are  of  any  use  to  them  in  their  ordinary  habits.  It  is  pos- 
sible that  the  immense  beard  of  the  male  Pithecia,  and  the 
large  beard  of  the  male  orang,  may  protect  their  throats 
when  fighting  ;  for  the  keepers  in  the  Zoological  Gardens 
inform  me  that  many  monkeys  attack  each  other  by  the 
throat;  but  it  is  not  probable  that  the  beard  has  been 
developed  for  a  distinct  purpose  from  that  served  by  the 
whiskers,  mustache  and  other  tufts  of  hair  on  the  face; 
and  no  one  will  suppose  that  these  are  useful  as  a  protec- 
tion. Must  we  attribute  all  these  appendages  of  hair  or 
skin  to  mere  purposeless  variability  in  the  male?  It  cannot 
be  denied  that  this  is  possible;  for  in  many  domesticated 
quadrupeds  certain  characters,  apparently  not  derived 
through  reversion  from  any  wild  parent  form,  are  confined 
to  the  males,  or  are  more  developed  in  them  than  in 
females;  for  instance,  the  hump  on  the  male  zebu-cattle  of 
India,  the  tail  of  fat-tailed  rams,  the  arched  outline  of  the 
forehead  in  the  males  of  several  breeds  of  sheep,  and, 
lastly,  the  mane,  the  long  hairs  on  the  hind  legs,  and  the 
dewlap  of  the  male  of  the  Berbura  goat.*  The  mane, 
which  occurs  only  in  the  rams  of  an  African  breed  of 
sheep,  is  a  true  secondary  sexual  character,  for,  as  I  hear 
from  Mr.  Win  wood  Reade,  it  is  not  developed  if  the  animal 
be  castrated.  Although  we  ought  to  be  extremely  cautious, 
as  shown  in  my- work  on  '^  Variation  under  Domestication," 
in  concluding  that  any  character,  even  with  animals  kept 
by  semi-civilized  people,  has  not  been  subjected  to  selec- 
tion by  man,  and  thus  augmented,  yet  in  the  cases  just 
specified  this  is  improbable;  more  especially  as  the  charac- 
ters are  confined  to  the  males,  or  are  more  strongly  devel- 
oped in  them  than  in  the  fetnales.     If  it  were  positively 

*  See  the  chapters  on  these  several  animals  in  vol.  i,  of  my 
"  Variation  of  Animals  under  Domestication;"  also  vol.  ii,  p.  73;  also 
chap.  XX,  on  the  practice  of  selection  by  serai-civilized  people.  For 
the  Berbura  goat,  see  Dr.  Gray,  "  Catalogue,"  ibid,  p.  157. 


MAMMALS.  609 

known  that  the  above  African  ram  is  a  descendant  of  the 
same  primitive  stock  as  the  other  breeds  of  sheep,  and  if 
the  Berbura  male  goat,  with  his  mane,  dewlap,  etc.,  is 
descended  from  the  same  stock  as  other  goats,  then, 
assuming  that  selection  has  not  been  applied  to  these 
characters,  they  must  be  due  to  simple  variability,  together 
with  sexually  limited  inheritance. 

Hence  it  appears  reasonable  to  extend  this  same  view  to 
all  analagous  cases  with  animals  in  a  state  of  nature. 
Nevertheless  I  cannot  persuade  myself  that  it  generally 
holds  good,  as  in  the  case  of  the  extraordinary  development 
of  hair  on  the  throat  and  fore  legs  of  the  male  Ammo- 
tragus,  or  in  that  of  the  immense  beard  of  the  male 
Pithecia.  Such  study  as  I  have  been  able  to  give  to  nature 
makes  me  believe  that  parts  or  organs  which  are  highly 
developed  were  acquired  at  some  period  for  a  special  pur- 
pose. With  those  antelopes  in  which  the  adult  male  is 
more  strongly  colored  than  the  female,  and  with  those 
monkeys  on  which  the  hair  on  the  face  is  elegantly  arranged 
and  colored  in  a  diversfied  manner,  it  seems  probable  that 
the  crests  and  tufts  of  hair  were  gained  as  ornaments;  and 
this  I  know  is  the  opinion  of  some  naturalists.  If  this  be 
correct,  there  can  be  little  doubt  that  they  were  gained  or 
at  least  modified  through  sexual  selection  ;  but  how  far 
the  same  view  may  be  extended  to  other  mammals  is 
doubtful. 

Color  of  the  Hair  and  of  the  Naked  Skin. — I  will  first 
give  briefly  all  the  cases  known  to  me  of  male  quadrupeds 
differing  in  color  from  the  females.  With  marsupials,  as  I 
am  informed  by  Mr.  Grould,  the  sexes  rarely  differ  in  this 
respect;  but  the  great  red  kangaroo  offers  a  striking  excep- 
tion, *^  delicate  blue  being  the  prevailing  tint  in  those  parts 
of  the  female  which  in  the  male  are  red."*  In  the 
Didelphis  opossum  of  Cayenne  the  female  is  said  to  be  a 
little  more  red  than  the  male.  Of  the  rodents,  Dr.  Gray 
remarks:  '^African  squirrels,  especially  those  found  in  the 
tropical  regions,  have  the  fur  much  brighter  and  more  vivid 
at  some  seasons  of  the  year  than  at  others,  and  the  fur  of 

*08phranter  rufiis,  Gould,  "Mammals  of  Australia,"  1863,  vol. 
U.     On  the  Didelphis,  Desmarest,  "  Mammalogie,"  p.  35§, 


610  THK  DESCENT  OF  MAN. 

the  male  is  generally  brighter  than  that  of  the  female."* 
Dr.  Gray  informs  me  that  he  specified  the  African  squir- 
rels, because,  from  their  unusually  bright  colors,  they  best 
exhibit  this  difference.  The  female  of  the  Mus  mimitus 
of  Russia  is  of  a  paler  and  dirtier  tint  than  the  male.  In  a 
large  number  of  bats  the  fur  of  the  male  is  lighter  than  in 
female,  f  Mr.  Dobson  also  remarks,  with  respect  to  these 
animals:  "Differences,  depending  partly  or  entirely  on  the 
possession  by  the  male  of  fur  of  a  much  more  brilliant  hue, 
or  distinguished  by  different  markings  or  by  the  greater 
length  of  certain  portions,  are  met  only,  to  any  appreciable 
extent,  in  the  frugivorous  bats  in  which  the  sense  of  sight 
is  well  developed."  This  last  remark  deserves  attention, 
as  bearing  on  the  question  whether  bright  colors  are  ser- 
viceable to  male  animals  from  being  ornamental.  In  one 
genus  of  sloths  it  is  now  established,  as  Dr.  Gray  states, 
*'  that  the  males  are  ornamented  differently  from  the 
females — that  is  to  say,  that  they  have  a  patch  of  soft  short 
hair  between  the  shoulders,  which  is  generally  of  a  more 
or  less  orange  color,  and  in  one  species  pure  white.  The 
females,  on  the  contrary,  are  destitute  of  this  mark." 

The  terrestrial  Carnivora  and  Insectivora  rarely  exhibit 
sexual  differences  of  any  kind,  including  color.  The  ocelot 
(Felis  pardalis),  however,  is  exceptional,  for  the  colors  of 
the  female,  compared  with  those  of  the  male,  are  '^moins 
apparentes,  le  fauve,  etant  plus  terne,  le  blanc  moins  pur, 
les  raies  ayant  moins  de  largeur  et  les  taches  moins  de 
diametre."J;  The  sexes  of  the  allied  i^eZis  mitis  also  differ, 
but  in  a  less  degree;  the  general  hues  of  the  female  being 
rather  paler  than  in  the  male,  with  the  spots  less  black. 
The  marine  Carnivora  or  seals,  on  the  other  hand,  some- 
times differ  considerably  iu  color,  and  they  present,  as  we 
have  already  seen,  other  remarkable  sexual  differences. 
Thus  the  male  of  the  Otaria  nigresceiis  of  the  southern 
hemisphere  is  of  a  rich  brown  shade  above  ;   while  the 

*  "  Annals  and  Mag.  of  Nat.  Hist.,"  Nov.,  1867,  p.  325.  On  tlie 
Mus  minutiis,  Desmarest,  "Mammalogie,"  p.  304. 

f  J.  A.  Allen,  in  "Bulletin  of  Mus.  Comp.  Zoolog.  of  Cambridge, 
United  States,"  1869,  p.  207.  Mr.  Dobson  on  sexual  characters  in 
the  Chiroptera,  "  Proc.  Zoolog.  Soc,"  1873,  p.  241.  Dr.  Gray  on 
sloths,  ibid,  1871,  p.  436. 

!:  Desmarest.  "  Mammalogie,"  1820,  p.  220.  On  Felis  Mitis,  Reng- 
ger,  ibid,  s.  194. 


MAMMALS.  611 

female,  who  acquires  her  adult  tints  earlier  in  life  than  the 
male,  is  dark-gray  above,  the  young  of  both  sexes  being  of 
a  deep  chocolate  color.  The  male  of  the  northern  Phoca 
groenlandica  is  tawny  gray,  with  a  curious  saddle-shaped 
dark  mark  on  the  back;  the  female  is  much  smaller  and 
has  a  very  different  appearance,  being  "  dull  white  or  yel- 
lowish straw-color,  with  a  tawny  hue  on  the  back;"  the 
young  at  first  are  pure  white,  and  can  "  hardly  be  dis- 
tinguished among  the  icy  hummocks  and  snow,  their  color 
thus  acting  as  a  protection."* 

With  ruminants  sexual  differences  of  color  occur  more 
commonly  than  in  any  other  order.  A  difference  of  this 
kind  is  general  in  the  Strepsicerene  antelopes;  thus  the 
male  nilghau  {Portax  jncta)  is  bluish-grey  and  much  darker 
than  the  female,  with  the  square  white  patch  on  the  throat, 
the  white  marks  on  the  fetlocks  and  the  black  spots  on  the 
ears  all  much  more  distinct.  We  have  seen  that  in  this 
species  the  crests  and  tuft  of  hair  are  likewise  more  devel- 
oped in  the  male  than  in  the  hornless  females.  I  am 
informed  by  Mr.  Blyth  that  the  male,  without  shedding 
his  hair,  periodically  becomes  darker  during  the  breeding- 
season.  Young  males  cannot  be  distinguished  from  young 
females  until  about  twelve  months  old;  and  if  the  male  is 
emasculated  before  this  period,  he  never,  according  to  the 
same  authority,  changes  color.  The  importance  of  this 
latter  fact,  as  evidence  that  the  coloring  of  the  Portax  is  of 
sexual  origin,  becomes  obvious  when  we  hearf  that  neither 
the  red  summer  coat  nor  the  blue  winter  coat  of  the  Virginian 
deer  is  at  all  affected  by  emasculation.  With  most  or  all  of 
the  highly  ornamented  species  of  Tregelaphus  the  males  are 
darker  than  the  hornless  females,  and  their  crests  of  hair  are 
more  fully  developed.  In  the  male  of  that  magnificent  ante- 
lope, the  Derbyan  eland,  the  body  is  redder,  the  whole  neck 
much  blacker  and  the  white  band  which  separates  these 
colors  broader  than  in  the  female.  In  the  Cape  eland,  also, 
the  male  is  slightly  darker  than  the  female.  | 

*Dr.  Murie  on  the  Otaria,  "  Proc.  Zool.  Soc.,"  1869,  p.  108.  Mr. 
R.  Brown  on  the  P.  groenlandica,  ibid,  1868,  p.  417.  See  also  on  the 
colors  of  seals,  Desniarest,  ibid,  pp.  243,  249. 

f  Judge  Caton,  in  "Trans.  Ottawa  Acad,  of  Nat.  Sciences,"  1868, 
p.  4. 

XDt.  Gray,  "Cat.  of  Mamm.  in  Brit.  Mas.,"  part  iii,  1852,  pp. 
134-142;  also  Dr.  Gray,  "Gleanings  from  the  Menagerie  of  Knows- 


612  THE  DESCENT  OF  MAN. 

In  the  Indian  black  -  buck  (^4.  hezoartica),  which 
belongs  to  anotlier  tribe  of  antelopes,  the  male  is  very 
dark,  almost  black  ;  while  the  hornless  female  is  fawn- 
colored.  We  meet  in  this  species,  as  Mr.  Blyth  informs 
me,  with  an  exactly  similar  series  of  facts,  as  in  the 
Portax  picta,  namely,  in  the  male  periodically  changing 
color  during  the  breeding-season,  in  the  effects  of  emascu- 
lation on  this  change,  and  in  the  young  of  both  sexes  being 
indistinguishable  from  each  other.  In  the  AnfAlope  niger 
the  male  is  black,  the  female,  as  well  as  the  young  of  both 
sexes,  being  brown;  in  A.  sing-sing  the  male  is  much 
brighter-colored  than  the  hornless  female,  and  his  chest 
and  belly  are  blacker;  in  the  male  A.  caama  the  marks 
and  lines  which  occur  on  various  parts  of  the  body  are 
black,  instead  of  brown  as  in  the  female;  in  the  brindled 
gnu  (A.  gorgon)  ^'  the  colors  of  the  male  are  nearly  the 
same  as  those  of  the  female,  only  deeper  and  of  a  brighter 
hue."  *     Other  analogous  cases  could  be  added. 

The  Banteng  bull  {Bos  smiclaiciis)  of  the  Malayan  Archi- 
pelago is  almost  black,  with  white  legs  and  buttocks;  the 
cow  is  of  a  bright  dun,  as  are  the  young  males  until  about 
the  age  of  three  years,  when  they  rapidly  change  color. 
The  emasculated  bull  reverts  to  the  color  of  the  female.  The 
female  Kemas  goat  is  paler,  and  both  it  and  the  female  Capra 
cegagrus  are  said  to  be  more  uniformly  tinted  than  their 
males.  Deer  rarely  present  any  sexual  differences  in  color. 
Judge  Caton,  however,  informs  me  that  in  the  males  of  the 
wapiti  deer  (Cervus  canade?isis)  the  neck,  belly  and  legs 
are  much  darker  than  in  the  female;  but  during  the 
winter  the  darker  tints  gradually  fade  away  and  disappear. 
I  may  here  mention  that  Judge  Caton  has  in  his  park  three 
races  of  the  Virginian  deer  which  differ  slightly  in  color, 
but  the  differences  are  almost  exclusively  confined  to  the 
blue  winter  or  breeding  coat;  so  that  this  case  may  be  com- 

ley,"  in  which  there  is  a  splendid  drawing  of  the  Oreas  derhianus: 
see  the  text  on  Tragelaphus.  For  the  Cape  eland  {Oreas  carina),  see 
Andrew  Smith,  "Zoology  of  S.  Afri<^a,"  pi,  41,  42.  There  are  also 
many  of  these  antelopes  in  the  Zoological  Gardens, 

*0n  the  Ant.  niger,  see  "Proc,  Zool.  Soc,"  1850,  p.  133.  With 
respect  to  an  allied  species,  in  which  there  is  an  equal  sexual  differ- 
ence in  color,  see  Sir  S.  Baker,  "The  Albert  Nyanza,"  1866,  vol.  ii, 
p  627,  For  the  A.  sing-sing,  Gray,  "  Cat.  B.  Mus.,"  p.  100.  Des- 
marest,  "  Mammalogie,"  p.  468,  on  the  A.  caama,  Andrew  ^mith, 
•*  Zoology  of  S.  Africa,"  on  the  gnu, 


MAMMALS.  613 

}):ired  with  those  given  in  a  previons  chapter  of  closely 
allied  or  representative  species  of  birds  which  differ  from 
each  other  only  in  their  breeding  plumage.*  The  females 
of  Cervus  paludosus  of  South  America,  as  well  as  the 
young  of  both  sexes,  do  not  possess  the  black  stripes  on  the 
nose  and  the  blackish-brown  line  on  the  breast  which  are 
characteristic  of  the  adult  males,  f  Lastly,  as  I  am 
informed  by  Mr.  Blyth,  the  mature  male  of  the  beautifully 
colored  and  spotted  axis  deer  is  considerably  darker  than 
the  female ;  and  this  hue  the  castrated  male  never 
acquires. 

The  last  order  which  we  need  consider  is  that  of  the 
Primates.  The  male  of  the  Lemur  macaco  is  generally 
coal-black,  while  the  female  is  brown.  J  Of  the  Quadru- 
mana  of  the  New  AVorld,  the  females  and  young  of  Mycetes 
caraya  are  grayish-yellow  and  like  each  other;  in  the  second 
year  the  young  male  becomes  reddish-brown;  in  the  third, 
black,  excepting  the  stomach,  which,  however,  becomes 
quite  black  in  the  fourth  or  fifth  year.  There  is  also  a 
strongly  marked  difference  in  color  between  the  sexes  of 
Mycetes  seniculus  and  Cebus  capucinus;  the  young  of  the 
former,  and  I  believe  of  the  latter  species,  resembling  the 
females.  With  Pithecia  leucocephala  the  young  likewise 
resemble  the  females,  which  are  brownish-black  above  and 
light  rusty-red  beneath,  the  adult  males  being  black.  The 
ruff'  of  hair  round  the  face  of  Ateles  margiriatus  is  tinted 
yellow  in  the  male  and  white  in  the  female.  Turning  to 
the  Old  World,  the  males  of  Hylohates  hoolock  are  always 
black,  with  the  exception  of  a  white  band  over  the  brows; 
the  females  vary  from  whitish-brown  to  a  dark  tint  mixed 
with  black,  but  are  never  wholly  black.  §     In  the  beautiful 

*  "  Ottawa  Academy  of  Sciences,"  May  21,  1868,  pp.  3,  5. 

fS.  Muller,  on  the  Banteng,  "Zool.  Indischen  Arcbipel.,"  1839- 
1844,  tab.  35;  see  also  Raffles,  as  quoted  by  Mr.  Blytb,  in  "  Land 
and  Water,"  1867,  p  476.  On  goats,  Dr.  Gray,  "Cat.  Brit.  Mus.," 
p.  146;  Desmarest,  "  Mammal ogie,"  p.  482.  On  the  Cervus  palu- 
dosus, Rengger,  ibid,  s.  345. 

ISclater,  " Proc.  Zool.  Soc,"  1866,  p.  1.  The  same  fact  has  also 
been  fully  ascertained  by  MM.  Pollen  and  van  Dam.  See,  also,  Dr. 
Gray  in  '*  Annals  and  Mag.  of  Nat.  Hist.,"  May,  1871,  p.  340. 

§0n  Mycetes.  Rengger,  ibid,  s.  14;  and  Brehm,  "  Illustrirtes 
Thierleben,"  B.  i,  ss.  96,  107.  On  Ateles  Desmarest,  "Mamuial- 
ogie,"  p.  75.  On 'Hylobates,  Blyth,  "Land  and  Water,"  1867,  p. 
135.  On  the  Semnopithecus,  S,  Muller,  "  Zoog.  Indischen  Archi- 
pel.,"  tab.  X. 


61 4  "TUB  DECENT  OP  MAN. 

Cercopithecus  dmiia,  the  head  of  the  adult  male  is  of  an 
intense  black,  while  that  of  the  female  is  dark  gray;  in  tlie 
former  the  fur  between  the  thighs  is  of  an  elegant  fawn- 
color,  in  the  latter  it  is  paler.  In  the  beautiful  and  curious 
mustache  monkey  (Cercopithecus  cephus)  the  only  differ- 
ence between  the  sexes  is  that  the  tail  of  the  male  is 
chestnut  and  that  of  the  female  gray;  but  Mr.  Bartlett 
informs  me  that  all  the  hues  become  more  pronounced  in 
the  male  when  adult,  while  in  the  female  they  remain  as 
they  Avere  during  youth.  According  to  the  colored  figures 
given  by  Solomon  Muller,  the  male  of  SemnopWiecus 
chrysomelas  is  nearly  black,  the  female  being  pale  brown. 
In  the  Cercopithecus  cynosures  and  griseoviridis  one  part 
of  the  body,  which  is  confined  to  the  male  sex,  is  of  the 
most  brilliant  blue  or  green,  and  contrasts  strikingly  with 
the  naked  skin  on  the  hinder  part  of  the  body,  which  is 
vivid  red. 

Lastly,  in  the  baboon  family,  the  adult  male  of  Cyno- 
cephalus  hamadryas  differs  from  the  female  not  only  by  his 
immense  mane,  but  slightly  in  the  color  of  the  hair  and 
of  the  nalred  callosities.  In  the  drill  {C.  leucophcsus)  the 
females  and  young  are  much  paler  colored,  with  less  green 
than  the  adult  males.  No  other  member  in  the  whole 
class  of  mammals  is  colored  in  so  extraordinary  a  manner 
as  the  adult  male  mandrill  {C.  inormon).  The  face  at  this 
age  becomes  of  a  fine  blue,  with  the  ridge  and  tip  of  the 
nose  of  the  most  brilliant  red.  According  to  some  authors 
the  face  is  also  marked  with  whitish  stripes,  and  is  shaded 
in  parts  with  black,  but  the  colors  appear  to  be  variable. 
On  the  forehead  there  is  a  crest  of  hair,  and  on  the  chin  a 
yellow  beard.  **Toutes  les  parties  superieures  de  leurs 
cuisses  et  le  grand  espace  nu  de  leurs  fesses  sont  egalement 
colores  du  rouge  le  plus  vif,  avec  un  melange  de  bleu  qui 
ne  manque  reellement  pas  d'elegance."*  When  the  animal 
is  excited  all  the  naked  parts  become  much  more  vividly 
tinted.  Several  authors  have  used  the  strongest  expres- 
sions in  describing  these  resplendent  colors,  which  they  com- 
pare with  those  of  the  most  brilliant  birds.    Another  remark- 

*Gervais,  "Hist.  Nat.  des  Mammiferes,"  1854,  p.  103.  Figures 
are  given  of  the  skull  of  the  male.  Also  Desmarest,  "  Mammal- 
ogie."  p.  70.  GeofEroy  St.-Hilaire  and  F.  Cuvier,  "Hist.  Nat.  des 
Mamna.,"  1824,  torn.  i. 


MAMMALS, 


615 


able  peculiarity  is  that  when  the  great  canine  teeth  are 
fully  developed,  immense  protuberances  of  bone  are  formed 
on  each  cheek,  which  are  deeply  furrowed  longitudinally, 
and  the  naked  skin  over  thorn  is  brilliantly  colored,  as  just 
described.  (Fig-  69.)  In  the  adult  females  and  in  the 
young  of  both  sexes  these  protuberances  are  scarcely  per- 


FijET.  69.   Head  of  male  Mandrill  (from  Gervais,  "  Hist.  Nat.  des  Mammiferes  "). 


ceptible;  and  the  naked  parts  are  much  less  bright  colored, 
the  face  being  almost  black,  tinged  with  blue.  In  the 
adult  female,  however,  the  nose  at  certain  regular  intervals 
of  time  becomes  tinted  with  red. 


In  all  the  cases  hitherto  given  the  male  is  more  strongly 
or  brighter  colored  than  the  female,  and  differs  from  the 


ei6  THE  DESCENT  OF  MAN. 

young  of  both  sexes.  But  as  with  some  few  birds  it  is  the 
female  which  is  brigliter  colored  than  the  male,  so  with 
the  Rhesus  monkey  {Macacus  rhesus),  the  female  has  a 
large  surface  of  naked  skin  round  the  tail,  of  a  brilliant 
carmine  red,  which,  as  I  was  assured  by  the  keepers  in  the 
Zoological  Gardens,  periodically  becomes  even  yet  more 
vivid,  and  her  face  also  is  pale  red.  On  the  other  hand,  in 
the  adult  male  and  in  the  young  of  both  sexes  (as  I  saw  in 
the  gardens),  neither  tlie  naked  skin  at  the  posterior  end 
of  the  body,  nor  the  face,  show  a  trace  of  red.  It  appears, 
however,  from  some  published  accounts,  that  the  male  does 
occasionall}^,  or  during  certain  seasons,  exhibit  'some  traces 
of  the  red.  Although  he  is  thus  less  ornamented  than  the 
female,  yet  in  the  larger  size  of  his  body,  larger  canine 
teeth,  more  developed  whiskers,  more  prominent  super- 
ciliary ridges,  he  follows  the  common  rule  of  the  male  ex- 
celling the  female. 

I  have  now  given  all  the  cases  known  to  me  of  a  dif- 
ference in  color  between  the  sexes  of  mammals.  Some  of 
these  may  be  the  result  of  variations  confined  to  one  sex 
and  transmitted  to  the  same  sex,  without  any  good  being 
gained,  and  therefore  without  the  aid  of  selection.  We 
have  instances  of  this  with  our  domesticated  animals,  as  in 
the  males  of  certain  cats  being  rusty-red,  while  the  females 
are  tortoise-shell  colored.  Analogous  cases  occur  in  nature: 
Mr.  Bartlett  has  seen  many  black  varieties  of  the  jaguar, 
leopard,  vulpine  phalanger  and  wombat;  and  he  is  certain 
that  all,  or  nearly  all  these  animals,  were  males.  On  the 
other  hand,  with  wolves,  foxes,  and  apparently  American 
squirrels,  both  sexes  are  occasionally  born  black.  Hence 
it  is  quite  possible  that  with  some  mammals  a  difference  of 
color  between  the  sexes,  especially  when  this  is  congenital, 
may  simply  be  the  result,  without  the  aid  of  selection,  of 
the  occurrence  of  one  or  more  variations,  which  from  the 
first  were  sexually  limited  in  their  transmission.  Never- 
theless it  is  improbable  that  the  diversified,  vivid,  and  con- 
trasted colors  of  certain  quadrupeds,  for  instance,  of  the 
above  monkeys  and  antelopes,  can  thus  be  accounted  for. 
We  should  bear  in  mind  that  these  colors  do  not  appear  in 
the  male  at  birth,  but  only  at  or  near  maturity;  and  that, 
unlike  ordinary  variations,  they  are  lost  if  the  male  be 
emasculated.     It  is  on  the  whole  probable  that  the  strongly 


MAMMALS,  617 

marked  colors  and  other  ornamental  characters  of  male 
quadrupeds  are  beneficial  to  them  in  their  rivalry  with 
other  males,  and  have  consequently  been  acquired  through 
sexual  selection.  This  view  is  strengthened  by  the  dif- 
ferences in  color  between  the  sexes  occurring  almost  ex- 
clusively, as  may  be  collected  from  the  previous  details,  in 
those  groups  and  sub-groups  of  mammals  which  present 
other  and  strongly  marked  secondary  sexual  characters; 
these  being  likewise  due  to  sexual  selection. 

Quadrupeds  manifestly  take  notice  of  color.  Sir  S. 
Baker  repeatedly  observed  that  the  African  elephant  and 
rhinoceros  attacked  white  or  gray  horses  with  special  fury. 
I  have  elsewhere  shown*  that  half-wild  horses  apparently 
prefer  to  pair  with  those  of  the  same  color,  and  that  herds 
of  fallow-deer  of  different  colors,  though  living  together, 
have  long  kept  distinct.  It  is  a  more  significant  fact  that 
a  female  zebra  would  not  admit  the  addresses  of  a  male  ass 
until  he  was  painted  so  as  to  resemble  a  zebra,  and  then,  as 
John  Hunter  remarks,  ^^she  received  him  very  readily. 
In  this  curious  fact,  we  have  instinct  excited  by  mere 
color,  which  had  so  strong  an  effect  as  to  get  the  better  of 
everything  else.  But  the  male  did  not  require  this;  the 
female  being  an  animal  somewhat  similar  to  himself,  was 
sufficient  to  rouse  him.''  \ 

In  an  earlier  chapter  we  have  seen  that  the  mental 
powers  of  the  higher  animals  do  not  differ  in  kind,  though 
greatly  in  degree,  from  the  corresponding  powers  of  man, 
especially  of  the  lower  and  barbarous  races;  and  it  would 
appear  that  even  their  taste  for  the  beautiful  is  not  widely 
different  from  that  of  the  Quadrumana.  As  the  negro  of 
Africa  raises  the  flesh  on  his  face  into  parallel  ridges  ''  or 
cicatrices,  high  above  the  natural  surface,  which  unsightly 
deformities  are  considered  great  personal  attractions;" J — as 
negroes  and  savages  in  many  parts  of  the  world  paint  their 
faces  with  red,  blue,  white  or  black  bars — so  the  male  man- 
drill of  Africa  appears  to  have  acquired  his  deeply  furrowed 
and  gaudily  colored  face  from  having  been  thus  rendered 

♦"The  Variation  of  Animals  and  Plants  under  Domestication," 
1868,  vol.  ii,  pp.  102,  103. 

f  "  Essays  and  Observations  by  J.  Hunter,"  edited  by  Owen,  1861, 
vol.  i,  p.  194. 

JSir  S.  Baker,  "The  Nile  Tributaries  of  Abyssinia,"  1867. 


618  THE  DmCENT  OF  MAN. 

attractive  to  the  female.  No  doubt  it  is  to  us  a  most 
grotesque  notion  that  the  posterior  end  of  the  body  should 
be  colored  for  the  sake  of  ornament  even  more  brilliantly 
than  the  face;  but  this  is  not  more  strange  than  that  the 
tails  of  many  birds  should  be  especially  decorated. 

With  mammals  we  do  not  at  present  possess  any  evidence 
that  the  males  take  pains  to  display  their  charms  before 
the  female;  and  the  elaborate  manner  in  which  this  is  per- 
formed by  male  birds  and  other  animals  is  the  strongest 
argument  in  favor  of  the  belief  that  the  females  admire, 
or  are  excited  by,  the  ornaments  and  colors  displayed 
before  them.  There  is,  however,  a  striking  parallelism 
between  mammals  and  birds  in  all  their  secondary  sexual 
characters,  namely,  in  their  weapons  for  fighting  with  rival 
males,  in  their  ornamental  appendages  and  in  their  colors. 
In  both  classes,  when  the  male  differs  from  the  female,  the 
young  of  both  sexes  almost  always  resemble  each  other,  and 
in  a  large  majority  of  cases  resemble  the  adult  female.  In 
both  classes  the  male  assumes  the  characters  proper  to  his 
sex  shortly  before  the  age  of  reproduction;  and  if  emas- 
culated at  an  early  period  loses  them.  In  both  classes  the 
change  of  color  is  sometimes  seasonal,  and  the  tints  of  the 
naked  parts  sometimes  become  more  vivid  during  the  act  of 
courtship.  In  both  classes  the  male  is  almost  always  more 
vividly  or  strongly  colored  than  the  female,  and  is  orna- 
mented with  larger  crests  of  hair  or  feathers,  or  other 
such  appendages.  In  a  few  exceptional  cases  the  female  in 
both  classes  is  more  highly  ornamented  than  the  male. 
With  many  mammals,  and  at  least  in  the  case  of  one  bird, 
the  male  is  more  odoriferous  than  the  female.  In  both 
classes  the  voice  of  the  male  is  more  powerful  than  that  of 
the  female.  Considering  this  parallelism,  there  can  be 
little  doubt  that  the  same  cause,  whatever  it  may  be,  has 
acted  on  mammals  and  birds;  and  the  result,  as  far  as 
ornamental  characters  are  concerned,  may  be  attributed, 
as  it  appears  to  me,  to  the  long-continued  preference  of  the 
individuals  of  one  sex  for  certain  individuals  of  the  opposite 
sex,  combined  with  their  success  in  leaving  a  larger 
number  of  offspring  to  inherit  their  superior  attractions. 

Equal  Transmission  of  Ornamental  Characters  to  Both 
Sexes. — With  many  birds,  ornaments,  which  analogy  leads 
us  to  believe  were  primarily  acquired  by  the  males,  have 


MAMMALS.  GIO 

been  transmitted  equally,  or  almost  equally,  to  both  sexes; 
and  we  may  now  inquire  how  far  this  view  applies  to  mam- 
mals. With  a  considerable  number  of  species,  especially 
of  the  smaller  kinds,  both  sexes  have  been  colored,  inde- 
pendently of  sexual  selection,  for  the  sake  of  protection; 
but  not,  as  far  as  I  can  judge,  in  so  many  cases,  nor  in  so 
striking  a  manner,  as  in  most  of  the  lower  classes.  Audu- 
bon remarks  that  he  often  mistook  the  muskrat,*  while 
sitting  on  the  banks  of  a  muddy  stream,  for  a  clod  of  earth, 
BO  complete  was  the  resemblance.  The  hair  on  her  form  is 
a  familiar  instance  of  concealment  through  color;  yet  this 
principle  partly  fails  in  a  closely  allied  species,  the  rabbit, 
for  when  running  to  its  burrow,  it  is  made  conspicuous  to 
the  sportsman,  and,  no  doubt,  to  all  beasts  of  prey,  by  its 
upturned  white  tail.  No  one  doubts  that  the  quadrupeds 
inhabiting  snow-clad  regions  have  been  rendered  white  to 
protect  them  from  their  enemies,  or  to  favor  their  stealing 
on  their  prey.  In  regions  where  snow  never  lies  for  long, 
a  white  coat  would  be  injurious;  consequently,  species  of 
this  color  are  extremely  rare  in  the  hotter  parts  of  the 
world.  It  deserves  notice  that  many  quadrupeds  inhabit- 
ing moderately  cold  regions,  although  they  do  not  assume 
a  white  winter  dress,  become  paler  during  this  season;  and 
this  apparently  is  the  direct  result  of  the  conditions  to 
which  they  have  long  been  exposed.  Pallas  f  states  that  in 
Siberia  a  change  of  this  nature  occurs  with  the  wolf,  two 
species  of  Mustela,  the  domestic  horse,  the  Equus  heinionus, 
the  domestic  cow,  two  species  of  antelopes,  the  musk-deer, 
the  roe,  elk  and  reindeer.  The  roe,  for  instance,  has  a  red 
summer  and  a  grayish- white  winter  coat;  and  the  latter 
may,  perhaps,  serve  as  a  protection  to  the  animal  while 
wandering  through  the  leafless  thickets,  sprinkled  with 
snow  and  hoar-frost.  If  the  above-named  animals  were 
gradually  to  extend  their  range  into  regions  perpetually 
covered  with  snow  their  pale  winter  coats  would  probably 
be  rendered,  through  natural  selection,  whiter  and  whiter, 
until  they  became  as  white  as  snow. 

Mr.  Reeks  has  given  me  a  curious  instance  of  an  animal 

*  Fiber  zibethievs,  Audubon  and  Bachman,  "The  Quadrupeds  of 
Nortb  America,"  1846,  p.  109. 

f  "Novae  species  Quadrupedum  e  Glirium  ordine,"  1778,  p.  7. 
What  I  have  called  the  roe  is  the  Capreolus  sibiriett^  subecandatus  of 
Pallas. 


G20 


THE  DESCENT  OF  MAN. 


profiting  by  being  peculiarly  colored.  He  raised  from  fifty 
to  sixty  white  and  brown  piebald  rabbits  in  a  large  walled 
orchard;  and  he  had  at  the  same  time  some  similarly 
colored  cats  in  his  house.  Such  cats,  as  I  have  often 
noticed,  are  very  conspicuous  during  the  day;  but,  as  they 


Fig.  70.    Tragelaphus  scriptus,  maie  (from  the  Knowsley  Menagerie). 


used  to  lie  in  watch  during  the  dusk  at  the  mouths  of  the 
burrows,  the  rabbits  apparently  did  not  distinguish  them 
from  their  party-colored  brethren.  The  result  was  tliat, 
within  eighteen  months,  every  one  of  these  party-colored 
rabbits  was  destroyed;  and  there  was  evidence  that  this 
was  effected  by  the  cats.  Color  seems  to  be  advantageous 
to  another  animal,  the  skunk,  in  a  manner  of  which  we 
have  had  many  instances  in  other  classes.  No  animal  will 
voluntarily  attack  one  of  these  creatures  on  account  of  the 
dreadful  odor  which  it  emits  when  irritated;  but  during  the 


MAMMALS.  621 

dusK  It  would  not  easily  be  recognized  and  might  be  attacked 
by  a  beast  of  prey.  Hence  it  is,  as  Mr.  Belt  believes,  *  that  the 
skunk  is  provided  with  a  great  white  bushy  tail,  which 
serves  as  a  conspicuous  warning. 

Although  we  must  admit  that  many  quadrupeds  have 
received  their  present  tints  either  as  a  protection,  or  as  an 
aid  in  procuring  prey,  yet  with  a  host  of  species,  the  colors 
are  far  too  conspicuous  and  too  singularly  arranged  to 
allow  us  to  suppose  that  they  serve  for  these  purposes.  We 
may  take  as  an  illustration  certain  antelopes;  when  we  see 
the  square  white  patch  on  the  throat,  the  white  marks  on 
the  fetlocks,  and  the  round  black  spots  on  the  ears,  all  more 
distinct  in  the  male  of  the  Portax  ^Jidrt,  than  in  the 
female — when  we  see  that  the  colors  are  more  vivid,  that 
the  narrow  white  lines  on  the  flank  and  the  broad  white 
bar  on  the  shoulder  are  more  distinct  in  the  male  Oreas 
(lerbyanus  than  in  the  female — when  we  see  a  similar 
difference  between  the  sexes  of  the  curiously  ornamented 
Tragelaplius  scriphis  (fig.  TO) — we  cannot  believe  that 
differences  of  this  kind  are  of  any  service  to  either  sex  in 
their  daily  habits  of  life.  It  seems  a  much  more  probable 
conclusion  that  the  various  marks  were  first  acquired  by 
the  males  and  their  colors  intensified  through  sexual  selec- 
tion, and  then  partially  transferred  to  tiie  females.  If  this 
view  be  admitted,  there  can  be  little  doubt  that  the  equally 
singular  colors  and  marks  of  many  other  antelopes,  though 
common  to  both  sexes,  have  been  gained  and  transmitted 
in  a  like  manner.  Both  sexes,  for  instance,  of  the  koodoo 
(Streps I ceros  kudu)  (fig.  64)  have  narrow  white  vertical 
lines  on  their  hind  flanks,  and  an  elegant  angular  white 
mark  on  their  foreheads.  Both  sexes  in  the  genus  Dam- 
alis  are  very  oddly  colored;  in  D.  pygarga  the  back  and 
neck  are  purplish-red,  shading  on  the  flanks  into  black  ; 
and  these  colors  are  abruptly  separated  from  the  white 
belly  and  from  a  large  white  space  on  the  buttocks;  the  head 
is  still  more  oddly  colored,  a  large  oblong  white  mask,  nar- 
rowly edged  with  black,  covers  the  face  up  to  the  eyes 
(fig.  71);  there  are  three  white  stripes  on  the  forehead  and 
the  ears  are  marked  with  white.  The  fawns  of  this  species 
are  of  a  uniform  pale  yellowish  brown.  In  Damalis  alhi- 
frons  the  coloring  of  the  head  differs  from  that  in  the  last 

*  "  The  Naturalist  in  Nicaragua,"  p.  249. 


622 


THE  BESVhJJVT  OF  MAN, 


species  in  a  single  wliite  stripe  replacing  the  three  stripes, 
and  in  the  ears  being  wholly  white.*  After  having  studied 
to  the  best  of  my  ability  the  sexual  differences  of  animals 
belonging  to  all  classes,  I  cannot  avoid  the  conclusion  that 
the  curiously  arranged  colors  of  many  antelopes,  though 


Fig.  71.    Damalis  pygarga,  male  (from  tne  Knowsley  Menagene). 


common  to  both  sexes,  are  the  result  of  sexual  selection 
primarily  applied  to  the  male. 

The  same  conclusion  may  perhaps  be  extended  to  the 
tiger,  one  of  the  most  beautiful  animals  in  the  world,  the 
sexes  of  which  cannot  be  distinguished  by  color,  even  by 
the  dealers  in  wild  beasts.  Mr.  Wallace  believesf  that  the 
striped  coat  of  the  tiger  '^  so  assimilates  with  the  vertical 

*See  tlie  fine  plates  in  A.  Smith's  "Zoology  of  S.  Africa,"  and  Dr. 
Gray's  "  Gleanings  from  the  Menagerie  of  Knowsley." 
f  "Westminster  Review,"  July  1, 1867,  p.  5. 


MAMMALS,  623 

stems  of  the  bamboo  as  to  assist  greatly  in  concealing  him 
from  his  approaching  prey/'  But  this  view  does  not 
appear  to  me  satisfactory.  We  have  some  slight  evidence 
that  his  beauty  may  be  due  to  sexual  selection,  for  in  two 
species  of  Felis  the  analagous  marks  and  colors  are  rather 
brighter  in  the  male  than  in  the  female.  The  zebra  is  con- 
spicuously striped,  and  stripes  cannot  afford  any  protection 
on  the  open  plains  of  S.  Africa.  Burchell  *  in  describing 
a  herd  says:  '^  Their  sleek  ribs  glistened  in  the  sun,  and  the 
brightness  and  regularity  of  their  striped  coats  presented  a 
picture  of  extraordinary  beauty,  in  which  probably  they  are 
not  surpassed  by  any  other  quadruped."  But  as  through- 
out the  whole  group  of  the  Equida?  the  sexes  are  identical 
in  color  we  have  here  no  evidence  of  sexual  selection. 
Nevertheless  he  who  attributes  the  white  and  dark  vertical 
stripes  on  the  flanks  of  various  antelopes  to  this  process, 
will  probably  extend  the  same  view  to  the  royal  tiger  and 
beautiful  zebra. 

AVe  have  seen  in  a  former  chapter  that  when  young  ani- 
mals belonging  to  any  class  follow  nearly  the  same  habits 
of  life  as  their  parents,  and  yet  are  colored  in  a  different 
manner,  it  may  be  inferred  that  they  have  retained  the 
coloring  of  some  ancient  and  extinct  progenitor.  In  the 
family  of  pigs,  and  in  the  tapirs,  the  young  are  marked 
with  longitudinal  stripes,  and  thus  differ  from  all  the  exist- 
ing adult  species  in  these  two  grou2)s.  AVith  many  kinds  of 
deer  the  young  are  marked  with  elegant  white  spots, 
of  which  their  parents  exhibit  not  a  trace.  A  graduated 
series  can  be  followed  from  the  axis  deer,  both  sexes  of 
which  at  all  ages  and  during  all  seasons  are  beautifully 
spotted  (the  male  being  rather  more  strongly  colored  than 
the  female),  to  species  in  which  neither  the  old  nor  the 
young  are  spotted.  I  will  specify  some  of  the  steps  in  this 
series.  The  Mantchurian  deer  (Cerviis  maiitcMiricics)  is 
spotted  during  the  whole  year,  but,  as  I  have  seen  in  the 
Zoological  Gardens,  the  spots  are  much  plainer  during  the 
summer,  when  the  general  color  of  the  coat  is  lighter  than 
during  the  winter,  when  the  general  color  is  darker  and  the 
horns  are  fully  developed.  In  the  hog-deer  (Hyelaphus 
porcinus)  the  spots  are  extremely  conspicuous  during  the 
summer  when  the  coat  is  reddish-brown,  but  quite  disap- 

♦  "  Travels  m  South  Africa,"  1824,  vol.  ii,  p.  315, 


624  THE  DESCENT  OF  MAN. 

pear  during  the  winter  when  the  coat  is  brown.*  In  both 
these  species  the  young  are  spotted.  In  the  Virginian  deer 
the  young  are  likewise  spotted,  and  about  five  per  cent  of  the 
adult  animals  living  in  Judge  Caton's  park,  as  I  am 
informed  by  him,  temporarily  exhibit  at  the  period  when 
the  red  summer  coat  is  being  replaced  by  the  bluish  winter 
coat,  a  row  of  spots  on  each  flank,  which  are  always  the 
same  in  number,  though  very  variable  in  distinctness. 
From  this  condition  there  is  but  a  very  small  step  to  the 
complete  absence  of  spots  in  the  adults  at  all  seasons;  and, 
lastly,  to  their  absence  at  all  ages  and  seasons,  as  occurs 
with  certain  species.  From  the  existence  of  this  perfect 
series,  and  more  especially  from  the  fawns  of  so  many 
species  being  spotted,  we  may  conclude  that  the  now  living 
members  of  the  deer  family  are  the  descendants  of  some 
ancient  species  which,  like  the  axis  deer,  was  spotted  at  all 
ages  and  seasons.  A  still  more  ancient  progenitor  probably 
somewhat  resembled  the  Hyomoschvs  aquaticus — for  this 
animal  is  spotted,  and  the  hornless  males  have  large 
exserted  canine  teeth,  of  which  some  few  true  deer  still 
retain  rudiments.  Hyomoschus,  also,  offers  one  of  those 
interesting  cases  of  a  form  linking  together  two  grouj^s,  for 
it  is  intermediate  in  certain  osteological  characters  between 
the  pachyderms  and  ruminants,  which  were  formerly 
thought  to  be  quite  distinct,  f 

A  curious  difficulty  here  arises.  If  we  admit  that 
colored  spots  and  stripes  were  first  acquired  as  ornaments, 
how  comes  it  that  so  many  existing  deer,  the  descendants 
of  an  aboriginally  spotted  animal,  and  all  the  species 
of  pigs  and  tapirs,  the  descendants  of  an  aboriginally 
striped  animal,  have  lost  in  their  adult  state  their  former 
ornaments  ?  I  cannot  satisfactorily  answer  this  question. 
We  may  feel  almost  sure  that  the  spots  and  stripes  disap- 
peared at  or  near  maturity  in  the  progenitors  of  our  exist- 
ing species,  so  that  they  were  still  retained  by  the  young; 
and,  owing  to  the  law  of  inheritance  at  corresponding  ages, 
were  transmitted  to  the  young  of  all  succeeding  generations. 

*Dr.  Gray,  "Gleanings  from  the  Menagerie  of  Knowsley,"  p.  64. 
Mr.  Blytb.  in  speaking  ('*  Land  and  Water,"  1869,  p.  42)  of  the  hog- 
deer  of  Ceylon,  says  it  is  more  brightly  spotted  with  white  than  the 
common  hog-deer,  at  the  season  when  it  renews  its  horns. 

f  Falconer  and  Cautley,  "  Proc.  Geolog.  Soc,"  1843:  and  Falconer's 
"  Pftl,  Memoirs,"  vol.  i,  p.  196, 


MAMMALS. 


625 


It  may  have  been  a  great  advantage  to  the  lion  and  puma,, 
from  the  open  nature  of  their  usual  haunts,  to  have  lost 
their  stripes,  and  to  have  been  thus  rendered  less  con- 
spicuous to  their  prey;  and  if  the  successive  variations,  by 
which  this  end  was  gained,  occurred  rather  late  in  life  the 
young  would  have  retained  their  stripes,  as  is  now  the  case. 


Fig.  72.  Head  of  Semnopithecus  rubicundus.  This  and  the  following  figures 
(from  Prof.  Gervais)  are  given  to  show  the  odd  arrangement  and  develop- 
ment of  the  hair  on  the  head. 


As  to  deer,  pigs  and  tapirs,  Fritz  Miiller  has  suggested  to 
me  that  these  animals,  by  the  removal  of  their  spots  or 
stripes  through  natural  selection,  would  have  been  less 
easily  seen  by  their  enemies;  and  that  they  would  have 
especially  required  this  protection  as  soon  as  the  carnivora 
increased  in  size  and  number  during  the  tertiary  periods. 
This  may  be  the  true  explanation,  but  it  is  rather  strange 
that  the  young  should  not  have  been  thus  protected,  and 
gtill  more  so  that  the  adults  of  some  species  should  have 


636  THE  DESCEHiT  OF  MAN. 

retained  their  spots,  either  partially  or  completely,  during 
part  of  the  year.  We  know  that  when  the  domestic  ass 
varies  and  becomes  reddish-brown,  gray  or  black  the  stripes 
on  the  shoulders  and  even  on  the  spine  frequently  disap- 
pear, though  we  cannot  explain  the  cause.  Very  few 
horses,  except  dun-colored  kinds,  have  stripes  on  any  part 
of  their  bodies,  yet  we  have  good  reason  to  believe  that  the 
aboriginal  horse  was  striped,  on  the  legs  and  spine,  and 
probably  on  the  shoulders.*  Hence  the  disappearance  of 
tlie  spots  and  stripes  in  our  adult  existing  deer,  pigs  and 
tapirs  may  be  due  to  a  change  in  the  general  color  of  their 
coats;  but  whether  this  change  was  effected  through  sexual 
or  natnral  selection,  or  was  due  to  the  direct  action  of  the 
conditions  of  life,  or  to  some  other  unknown  cause,  it  is 
impossible  to  decide.  An  observation  made  by  Mr.  Sclater 
well  illustrates  our  ignorance  of  the  laws  which  regulate 
the  appearance  and  disappearaiice  of  stripes;  the  species  of 
Asinus  which  inhabit  the  Asiatic  continent  are  destitute  of 
stripes,  not  having  even  the  cross  shoulder-stripe,  while 
those  which  inhabit  Africa  are  conspicuously  striped,  with 
the  partial  exception  of  A.  tmnlopus,  which  has  only  the 
cross  shoulder-strij^e  and  generally  some  faint  bars  on  the 
legs;  and  this  species  inhabits  the  almost  intermediate 
region  of  Upper  Egypt  and  Abyssinia,  f 

Qnadrumana. — Before  we  conclude,  it  will  be  well  to 
add  a  few  remarks  on  the  ornaments  of  monkeys.  In  most 
of  the  species  the  sexes  resemble  each  other  in  color,  but  in 
some,  as  we  have  seen,  the  males  differ  from  the  females, 
especially  in  the  color  of  the  naked  parts  of  the  skin,  in 
the  development  of  the  beard,  whiskers  and  mane.  Many 
species  are  colored  either  in  so  extraordinary  or  so  beautiful 
a  manner,  and  are  furnished  with  such  curious  and  elegant 
crests  of  hair,  that  we  can  hardly  avoid  looking  at  these 
characters  as  having  been  gained  for  the  sake  of  ornament. 
The  accompanying  figures  (72  to  76)  serve  to  show 
the  arrangement  of  the  hair  on  the  face  and  head  in  sev- 
eral species.     It  is  scarcely  conceivable  that  these  crests  of 

*"Tlie  Variation  of  Animals  and  Plants  under  Domestication," 
1868,  vol.  i,  pp.  61-64. 

\  "  Proc.  Zool.  Soc,"  1862,  p.  164.  See,  also,  Dr.  Hartman,  "  Ann, 
d.  Landw.,"  Bd.  xliii,  s.  222^. 


MAMMALS,  62? 

hair  and  the  strongly  contrasted  colors  of  the  fur  and  skin, 
can  be  the  result  of  mere  variability  without  the  aid  of  se- 
lection; and  it  is  inconceivable  that  they  can  be  of  use  in 
any  ordinary  way  to  these  animals.  If  so,  they  have 
probably  been  gained  through  sexual  selection,  though 
transmitted  equally,   or   almost  equally,    to    both    sexes. 


Fig.  73.  Head  of  Semnopithecus  comatus.      Fig.  74.    Head  of  Cebus  capucinus. 


Pig.  75.    Head  of  Ateles  marginatus.  Fig.  76.    Head  of  Cebus  vellerosus 


With  many  of  the  Quadrumana,  we  have  additional  evi- 
dence of  the  action  of  sexual  selection  in  the  greater  size 
and  strength  of  the  males,  and  in  the  greater  development 
of  their  canine  teeth,  in  comparison  with  the  females. 

A  few  instances  will  suffice  of  the  strange  manner  in 
which  both  sexes  of  some  species  are  colored  and  of  the 
beauty  of  others.     The  face  of  the  Cercopithemis  petaurista 


628  THE  DESCENT  OF  MAN. 

(fig.  77)  is  black,  the  whiskers  and  beard  being  white,  with 


Fig  77     ( 1 1(  opitiu  ( lis  petaurista  (from  Brehm). 

a  defined,  round,  white  spot  on   the   nose,  covered    with 
short  white  hair,  which  gives  to  the  animal  an  almost 


MAMMALS,  629 

ludicrous  aspect.  The  Semnopithectis  frontatus  likewise 
has  a  blackish  face  with  a  long  black  beard,  and  a  large 
naked  spot  on  the  forehead  of  a  bluish-white  color.  The 
face  of  Macacus  lasiotus  is  dirty  flesh-colored,  with  a 
defined  red  spot  on  each  cheek.  The  appearance  of 
Cercocehus  cethiops  is  grotesque,  with  its  black  face,  white 
whiskers  and  collar,  chestnut  head,  and  a  large  naked 
white  spot  over  each  eyelid.  In  very  many  species  the 
beard,  whiskers  and  crests  of  hair  round  the  face  are  of  a 
different  color  from  the  rest  of  the  head,  and,  when  differ- 
ent, are  always  of  a  lighter  tint,*  being  often  pure  white, 
sometimes  bright  yellow  or  reddish.  The  whole  face  of  the 
South  American  Brachyurus  calviis  is  of  a  *' glowing 
scarlet  hue;"  but  this  color  does  not  appear  until  the  ani- 
mal is  nearly  mature,  f  The  naked  skin  of  the  face  differs 
wonderfuU}' in  color  in  the  various  species.  It  is  often 
brown  or  flesh-color,  with  parts  perfectly  white,  and  often 
as  black  as  that  of  the  most  sooty  negro.  In  the  Brachyu- 
rus the  scarlet  tint  is  brighter  than  that  of  the  most  blush- 
ing Caucasian  damsel.  It  is  sometimes  more  distinctly 
oninge  than  in  any  Mongolian,  and  in  several  species  it  is 
blue,  passing  into  violet  or  gray.  In  all  the  species  known 
to  Mr.  Bartlett,  in  whicli  the  adults  of  both  sexes  have 
strongly  colored  faces,  the  colors  are  dull  or  absent  during 
early  youth.  This  likewise  holds  good  with  the  mandril 
and  rhesus,  in  which  the  face  and  the  posterior  parts  of  the 
body  are  brilliantly  colored  in  one  sex  alone.  In  these 
latter  cases  we  have  reason  to  believe  that  the  colors  were 
acquired  through  sexual  selection;  and  we  are  naturally  led 
to  extend  the  same  view  to  the  foregoing  species,  though 
both  sexes  when  adult  have  their  faces  colored  in  the  same 
manner. 

Although  many  kinds  of  monkeys  are  far  from  beautiful 
according  to  our  taste,  other  species  are  universally  ad- 
mired for  their  elegant  appearance  and  bright  colors.  The 
Semnopithecus  nemcens,  though  peculiarly  colored,  is  de- 
scribed as  extremely  pretty;  the  orange-tinted  face  is  sur- 
rounded by  long  whiskers  of  glossy  whiteness,  with  a  line  of 

*  I  observed  this  fact  in  the  Zoological  Gardens;  and  many  cases 
may  be  seen  in  the  colored  plates  in  Geoff roy  St.-Hilaire  and  F. 
Cuvier,  "Hist.  Nat,  des  Mamnii  feres,"  torn,  i,  1824. 

f  Bates,  "The  Naturalist  on  the  Amazons,"  1863,  vol.  ii,  p.  310. 


6S0  THE  DESCENT  OF  MAN. 

chestnut-red  over  the  eyebrows;  the  fur  on  the  back  is  of  a 
delicate  gray,  with  a  square  patch  on  the  loins,  the  tail 
and  the  fore  arms  being  of  a  pure  white;  a  gorget  of  chest- 
nut surmounts  the  chest;  the  thighs  are  black,  with  the 
legs  chestnut-red.  I  will  mention  only  two  other  monkeys 
for  their  beauty;  and  I  have  selected  these  as  presenting 
slight  sexual  differences  in  color,  which  renders  it  in  some 
degree  probable  that  both  sexes  owe  their  elegant  appear- 
ance to  sexual  selection.  In  the  mustache-monkey 
(Cercopifhecus  cephus)  the  general  color  of  the  fur  is  mot- 
tled-greenish with  the  throat  white;  in  the  male  the  end  of 
the  tail  is  chestnut,  but  the  face  is  the  most  ornamented 
part,  the  skin  being  chiefly  bluish-gray,  shading  into  a 
blackish  tint  beneath  the  eyes,  with  the  upper  lip  of  a  deli- 
cate blue,  clothed  on  the  lower  edge  with  a  thin  black 
mustache ;  the  whiskers  are  orange-colored,  with  the 
upper  part  black,  forming  a  band  which  extends  back- 
ward to  the  ears,  the  latter  being  clothed  with  whitish 
hairs.  In  the  Zoological  Society's  Gardens  I  have  often 
overheard  visitors  admiring  the  beauty  of  another  monkey, 
deservedly  called  Cercopifhecus  diana  (fig.  78);  the  general 
color  of  the  fur  is  gray;  the  chest  and  inner  surface  of  the 
fore  legs  are  white;  a  large  triangular  defined  space  on  the 
hinder  part  of  the  back  is  rich  chestnut;  in  the  male  the 
inner  sides  of  the  thighs  and  the  abdomen  are  delicate 
fawn-colored,  and  the  top  of  the  head  is  black;  the  face 
and  ears  are  intensely  black,  contrasting  finely  with  a  white 
transverse  crest  over  the  eyebrows  and  a  long  white  peaked 
beard,  of  which  the  basal  portion  is  black.* 

In  these  and  many  other  monkeys  the  beauty  and  sin- 
gular arrangement  of  their  colors,  and  still  more  the  diver- 
sified and  elegant  arrangement  of  the  crests  and  tufts  of 
hair  on  their  heads,  force  the  conviction  on  my  mind 
that  these  characters  have  been  acquired  through  sexual 
selection  exclusively  as  ornaments. 

Summary. — The  law  of  battle  for  the  possession  of  the 
female  appears  to  prevail  throughout  the  whole  great  class 
of  mammals.     Most  naturalists  will  admit  that  the  greater 

*  I  have  seen  most  of  the  above  monkeys  in  the  Zoological 
Society's  (hardens.  The  description  of  tlie  Semnopithecus  nemmus  is 
taken  from  Mr.  \V.  C.  Martin's  "Nat.  Hist,  of  Mammalia,"  1841,  p. 
460;  see  also  pp.  475.  523. 


MAMMALS. 


631 


size,  strength,  courage  and  pugnacity  of  the  male,  his 
special  weapons  of  offense,  as  well  as  his  special  means  of 
defense,  have  been  acquired  or  modified  through  that  form 
of  selection  which  I  have  called  sexual.  This  does  not 
depend  on  any  superiority  in  the  general  struggle  for  life. 


Kg.  78.    Cercopithecus  diana  (from  Brehm). 


but  on  certain  individuals  of  one  sex,  generally  the  male, 
being  successful  in  conquering  other  males,  and  leaving  a 
larger  number  of  offspring  to  inherit  their  superiority  than 
do  the  less  successful  males. 

There  is  another  and  more  i^aceful  kind  of  contest,  in 


632  THE  DE8CENT  OF  MAN, 

which  the  males  endeavor  to  excite  or  allure  the  females  by 
various  charms.  This  is  probably  carried  on  in  some  cases 
by  the  powerful  odors  emitted  by  the  males  during  the 
breeding-season ;  the  odoriferous  glands  having  been  acquired 
through  sexual  selection.  Whether  the  same  view  can  be 
extended  to  the  voice  is  doubtful,  for  the  vocal  organs  of 
the  males  must  have  been  strengthened  by  use  during 
maturity,  under  the  powerful  excitements  of  love,  jealousy 
or  rage,  and  will  consequently  have  been  transmitted  to  the 
same  sex.  Various  crests,  tufts  and  mantles  of  hair,  which 
are  either  confined  to  the  male,  or  are  more  developed  in 
this  sex  than  in  the  female,  seem  in  most  cases  to  be  merely 
ornamental,  though  they  sometimes  serve  as  a  defense 
against  rival  males.  There  is  even  reason  to  suspect  that 
the  branching  horns  of  stags  and  the  elegant  horns  of  cer- 
tain antelopes,  though  properly  serving  as  weapons  of 
offense  or  defense,  have  been  partly  modified  for  ornament. 
When  the  male  differs  in  color  from  the  female,  he  gen- 
erally exhibits  darker  and  more  strongly  contrasted  tints. 
We  do  not  in  this  class  meet  with  the  splendid  red,  blue, 
yellow  and  green  tints  so  common  with  maje  birds  and 
many  other  animals.  The  naked  parts,  however,  of  cer- 
tain Quadrumana  must  be  excepted;  for  such  parts,  often 
oddly  situated,  are  brilliantly  colored  in  some  species.  The 
colors  of  the  males  in  other  cases  may  be  due  to  simple 
variation  without  the  aid  of  selection.  But  when  the  colors 
are  diversified  and  strongly  pronounced,  when  they  are  not 
developed  until  near  maturity,  and  when  they  are  lost  after 
emasculation,  we  can  hardly  avoid  the  conclusion  that  they 
have  been  acquired  through  sexual  selection  for  the  sake  of 
ornament  and  have  been  transmitted  exclusively,  or  almost 
exclusively,  to  the  same  sex.  When  both  sexes  are  colored  in 
the  same  manner,  and  the  colors  are  conspicuous  or 
curiously  arranged,  without  being  of  the  least  apparent  use 
as  a  protection,  and  especially  when  they  are  associated 
with  various  other  ornamental  appendages,  we  are  led  by 
analogy  to  the  same  conclusion,  namely,  that  they  have 
been  acquired  through  sexual  selection,  although  trans- 
mitted to  both  sexes.  That  conspicuous  and  diversified 
colors,  whether  confined  to  the  males  or  common  to  both 
sexes,  are  as  a  general  rule  associated  in  the  same  groups 
and  sub-groups  with  other  secondary  sexual  characters  serv- 
ing for  war  or  for  ornament  will  be  found  to  hold  good,  if 


MAMMALS.  633 

we  look  back  to  tlie  various  cases  given  in  this  and  the 
last  chapter. 

The  law  of  the  equal  transmission  of  characters  to  both 
sexes,  as  far  as  color  and  other  ornaments  are  concerned, 
has  prevailed  far  more  extensively  with  mammals  than  with 
birds;  but  weapons,  such  as  horns  and  tusks,  have  often 
been  transmitted  either  exclusively  or  much  more  perfectly 
to  the  males  than  to  the  females.  This  is  surprising,  for, 
as  the  males  generally  use  their  weapons  for  defense  against 
enemies  of  all  kinds,  their  weapons  would  have  been  of 
service  to  the  females.  As  far  as  we  can  see  their  absence 
in  this  sex  can  be  accounted  for  only  by  the  form  of  inher- 
itance which  has  prevailed.  Finally,  with  quadrupeds  the 
contest  between  the  individuals  of  the  same  sex,  whether 
peaceful  or  bloody,  has,  with  the  rarest  exceptions,  been 
confined  to  the  males;  so  that  the  latter  have  been  modified 
through  sexual  selection,  far  more  commonly  than  the 
females,  either  for  fighting  with  each  other  or  for  alluring 
the  opposite  sex. 


PART  III. 
SEXUAL  SELECTION  IN  RELATION  TO  MAN. 


CHAPTER  XIX. 

SECONDARY   SEXUAL  CHARACTERS  OF  MAN. 

Differences  between  man  and  woman — Causes  of  such  differences 
and  of  certain  characters  common  to  both  sexes — Law  of  battle — 
Differences  in  mental  powers  and  voice — On  the  influence  of 
beauty  in  determinging  the  marriages  of  mankind — Attention 
paid  by  savages  to  ornaments — Their  ideas  of  beauty  in  woman — 
The  tendency  to  exaggerate  each  natural  peculiarity. 

With  mankind  the  differences  between  the  sexes  are 
greater  than  in  most  of  the  Quadrumana,  but  not  so  great 
as  in  some,  for  instance,  the  mandrill.  Man  on  an  average 
is  considerably  taller,  heavier  and  stronger  than  woman, 
with  squarer  shoulders  and  more  plainly  pronounced  mus- 
cles. Owing  to  the  relation  which  exists  between  muscular 
development  and  the  projection  of  the  brows,*  the  super- 
ciliary ridge  is  generally  more  marked  in  man  than  in 
woman.  His  body,  and  more  especially  his  face,  is  more 
hairy,  and  his  voice  has  a  different  and  more  powerful  tone. 
In  certain  races  the  women  are  said  to  differ  slightly  in  tint 
from  the  men.  For  instance,  Schweinfurth,  in  speaking  of 
a  negress  belonging  to  the  Monbuttoos,  who  inhabit  the 
interior  of  Africa  a  few  degrees  north  of  the  equator, 
says:  ^^Like  all  her  race,  she  had  a  skin  several  shades 
lighter  than  her  husband's,  being  something  of  tUe  color  of 
half -roasted  coffee."  f  -^s  the  women  labor  iu  the  fields 
and  are  quite  unclothed,  it  is  not  likely  that  they  differ  in 
color  from  the  men  owing  to  less  exposurt  to  the  weather. 

*  Schaaffhausen,  translation  in  "  Anthrjpological   Review,"  Oct., 
1868,  pp.  419,  420,  427. 
f  "  The  Heart  of  Africa,"  English  tran*»l.,  1873,  vol.  i,  p.  544. 


SECONDARY  SEXUAL  CHARACTERS.  635 

European  women  are  perhaps  the  brighter  colored  of  the 
two  sexes,  as  may  be  seen  when  both  have  been  equally 
exposed. 

Man  is  more  courageous,  pugnacious  and  energetic  than 
woman,  and  has  a  more  inventive  genius.  His  brain  is 
absolutely  larger,  but  whether  or  not  proportionately  to  his 
larger  body,  has  not,  I  believe,  been  fully  ascertained.  In 
woman  the  face  is  rounder;  the  jaws  and  the  base  of  the 
skull  smaller;  the  outlines  of  the  body  rounder,  in  parts 
more  prominent;  and  her  pelvis  is  broader  than  in  man  ;  * 
but  this  latter  character  may  perhaps  be  considered  rather 
as  a  primary  than  a  secondary  sexual  character.  She  comes 
to  maturity  at  an  earlier  age  than  man. 

As  with  animals  of  all  classes,  so  with  man,  the  dis- 
tinctive characters  of  the  male  sex  are  not  fully  developed 
until  he  is  nearly  mature;  and,  if  emasculated,  they  never 
appear.  The  beard,  for  instance,  is  a  secondary  sexual 
character,  and  male  children  are  beardless,  though  at  an 
early  age  they  have  abundant  hair  on  the  head.  It  is 
probably  due  to  the  rather  late  appearance  in  life  of  the 
successive  variations  whereby  man  has  acquired  his  mascu- 
line characters  that  they  are  transmitted  to  the  male  sex 
alone.  Male  and  female  children  resemble  each  other 
closely,  like  the  young  of  so  many  other  animals  in  which 
the  adult  sexes  differ  widely;  they  likewise  resemble  the 
mature  female  much  more  closely  than  the  mature  male. 
The  female,  however,  ultimately  assumes  certain  distinctive 
characters,  and,  in  the  formation  of  her  skull,  is  said  to  be 
intermediate  between  the  child  and  the  man.  f  Again,  as 
the  young  of  closely  allied  though  distinct  species  do  not 
differ  nearly  so  much  from  each  other  as  do  the  adults,  so 
it  is  with  the  children  of  the  different  races  of  man.  Some 
have  even  maintained  that  race  -  differences  cannot  be 
detected  in  the  infantile  skull.];  In  regard  to  color,  the 
new-born  negro  child  is  reddish  nut-brown,  which  soon 
becomes  slaty -gray;  the  black  color  being  fully  developed 

*Ecker,  translation  in  "Anthropological  Review,"  Oct.,  1868,  pp. 
351-356.  The  comparison  of  the  form  of  the  skull  in  men  and 
women  has  been  followed  out  with  much  care  by  Welcker. 

f Ecker  and  Welcker,  ibid,  pp,  352,  355;  Vogt,  "Lectures  on 
Man,"  Eng.  translat.,  p.  81. 

JSchaafEhausen,  "  Anthropolog.  Review,"  ibid,  p.  429. 


636  THE  PSSCJSNT  OF  MAK. 

within  a  year  in  the  Soiulan,  bnt  not  until  three  years  in 
Egypt.  The  eyes  of  the  negro  are  at  first  bhie,  and  tlie 
hair  chestnut-brown  rather  than  bhick,  being  curled  only 
at  the  ends.  The  children  of  the  Australians  immediately 
after  birth  are  yellowish-brown,  and  become  dark  at  a  later 
age.  Those  of  the  Guaranys  of  Paraguay  are  whitish- 
yellow,  but  they  acquire,  in  the  course  of  a  few  weeks,  the 
yellowish-brown  tint  of  their  parents.  Similar  observations 
have  been  made  in  other  parts  of  America.* 

I  have  specified  the  foregoing  differences  between  the 
male  and  female  sex  in  mankind,  because  they  are  curiously 
like  those  of  the  Quadrumana.  With  these  animals 
the  female  is  mature  at  an  earlier  age  than  the  male;  at 
least  this  is  certainly  the  case  in  Cebus  azarce.  \  The  males 
of  most  species  are  larger  and  stronger  than  the  females, 
of  which  fact  the  gorilla  affords  a  well-known  instance. 
Even  in  so  trifling  a  character  as  the  greater  prominence 
of  the  superciliary  ridge,  the  males  of  certain  monkeys 
differ  from  the  females,  J  and  agree  in  this  respect  with 
mankind.  In  the  gorilla  and  certain  other  monkeys  the 
cranium  of  the  adult  male  presents  a  strongly  marked 
sagittal  crest,  which  is  absent  in  the  female;  and  Ecker 
found  a  trace  of  a  similar  difference  between  the  two  sexes 
in  the  Australians.  §  With  monkeys,  when  there  is  any 
difference  in  the  voice,  that  of  the  male  is  the  more  pow- 
erful. We  have  seen  that  certain  male  monkeys  have  a 
well-developed  beard,  which  is  quite  deficient,  or  much  less 
developed,  in  the  female.  No  instance  is  known  of  the 
beard,  whiskers  or  mustache  being  larger  in  the  female  than 
in  the  male  monkey.  Even  in  the  color  of  the  beard  there 
is  a  curious  parallelism  between  man  and  the  Quadrumana, 

*Pruner-Bey,  on  negro  infants,  as  quoted  by  Vogt,  "  Lectures  on 
Man,"  Eng.  translat.,  1864,  p.  189;  for  further  facts  on  negro  infants, 
as  quoted  from  Winterbottom  and  Camper,  see  Lawrence,  "  Lectures 
on  Physiology,"  etc.,  1822,  p.  451.  For  the  infants  of  the  Guaranys, 
see  Rengger,  "  Saugethiere,"  etc.,  s.  3.  See  also  Godron,  "  De 
I'Espece,"  torn,  ii,  1859,  p.  253.  For  the  Australians,  Waitz,  "  Intro- 
duct,  to  Anthropology,"  Eng.  translat.,  1863,  p.  99. 

f  Rengger,  "  Saugethiere,"  etc,  1830,  s.  19. 

if  As  in  Macacus  cynomolgus  (Desmarest,  "Mammalogie,"  p.  65), 
and  in  Hylohates  agilifi  (Geoff roy  St.-Hilaire  and  F.  Cuvier,  "  Hist. 
Nat.  des  Mamm.,"  1824,  torn,  i,  p.  2). 

§  "  Anthropological  Review,"  Oct.,  1868,  p.  358. 


SECONDARY  SEXUAL  CHARACTERS,  637 

for  with  man  when  the  beard  differs  in  color  from  the  hair 
of  the  head,  as  is  commonly  the  case,  it  is,  I  believe,  almost 
always  of  a  lighter  tint,  being  often  reddish.  I  have 
repeatedly  observed  this  fact  in  England;  but  two  gentle- 
men have  lately  written  to  me,  saying  that  they  form  an 
exception  to  the  rule.  One  of  these  gentlemen  accounts 
for  the  fact  by  the  wide  difference  in  color  of  the  hair  on  the 
paternal  and  maternal  sides  of  his  family.  Both  had  long 
been  aware  of  this  peculiarity  (one  of  them  having  often  been 
accused  of  dyeing  his  beard),  and  had  been  thus  led  to  observe 
other  men,  and  were  convinced  that  the  exceptions  were 
very  rare.  Dr.  Hooker  attended  to  this  little  point  for  me 
in  Russia,  and  found  no  exception  to  the  rule.  In  Calcutta 
Mr.  J.  Scott,  of  the  Botanic  Gardens,  was  so  kind  as  to 
observe  the  many  races  of  men  to  be  seen  there,  as  well 
as  in  some  other  parts  of  India,  namely,  two  races  of 
Sikhim,  the  Bhoteas,  Hindoos,  Burmese  and  Chinese,  most 
of  which  races  have  very  little  hair  on  the  face;  and  he 
always  found  that  when  there  was  any  difference  in  color 
between  the  hair  of  the  head  and  the  beard,  the  latter  was 
invariably  lighter.  Xow  with  monkeys,  as  has  already 
been  stated,  the  beard  frequently  diffei*s  strikingly  in  color 
from  the  hair  of  the  head,  and  in  such  cases  it  is  always  of 
a  lighter  hue,  being  often  pure  white,  sometimes  yellow  or 
reddish.* 

In  regard  to  the  general  hairiness  of  the  body,  the 
women  in  all  races  are  less  hairy  than  the  men ;  and  in 
some  few  Quadrumana  the  under  side  of  the  body 
of  the  female  is  less  hairy  than  that  of  the  male.f 
Lastly,  male  monkeys,  like  men,  are  bolder  and   fiercer 

*  Mr.  Blyth  informs  me  that  he  has  only  seen  one  instance  of  the 
beard,  whiskers,  etc. ,  in  a  monkey  becoming  white  with  old  age,  as 
is  so  commonly  the  case  with  us.  This,  however,  occurred  in  an 
aged  Macaeu8  cynomolgus,  kept  in  confinement,  whose  mustaches 
were  "  remarkably  long  and  human-like."  Altogether  this  old 
monkey  presented  a  ludicrous  resemblance  to  one  of  the  reigning 
monarchs  of  Europe,  aft«r  whom  he  was  universally  nick-named. 
In  certain  races  of  man  the  hair  on  the  head  hardly  ever  becomes 
gray;  thus  Mr.  D.  Forbes  has  never,  as  he  informs  me,  seen  an 
instance  with  the  Aymaras  and  Quchuas  of  South  America, 

f  This  is  the  case  with  the  females  of  several  species  of  Hylobates. 
See  Geoffroy  St.-Hilaire  and  F.  Cuvier,  "Hist.  Nat.  des  Mamm.," 
tom.  i.  See,  also,  on  H.  lar,  "Penny  Cyclopedia,"  vol.  ii,  pp.  149, 
150. 


638  THE  DESCENT  OF  MAN, 

than  the  females.  They  lead  the  troop,  and,  when  there  is 
danger,  come  to  the  front.  We  thus  see  how  close  is  the 
parallelism  between  the  sexual  differences  of  man  and  the 
Quadrumana.  With  some  few  species,  however,  as  with 
certain  baboons,  the  orang  and  the  gorilla,  there  is  a  con- 
siderably greater  difference  between  the  sexes,  as  in  the 
size  of  the  canine  teeth,  in  the  development  and  color  of 
the  hair,  and  especially  in  the  color  of  the  naked  parts  of 
the  skin,  than  in  mankind. 

All  the  secondary  sexual  characters  of  man  are  highly 
variable,  even  within  the  limits  of  the  same  race;  and  they 
differ  much  in  the  several  races.  These  two  rules  hold 
good  generally  throughout  the  animal  kingdom.  In  the 
excellent  observations  made  on  board  the  ^^Novara,'^*  the 
male  Australians  were  found  to  exceed  the  females  by  only 
sixty-five  millimeters  in  height,  while  with  the  Javans  the 
average  excess  was  two  hundred  and  eighteen  millimeters; 
so  that  in  this  latter  race  the  difference  in  height  between  the 
sexes  is  more  than  thrice  as  great  as  with  the  Australians. 
Numerous  measurements  were  carefully  made  of  the  stat- 
ure, the  circumference  of  the  neck  and  chest,  the  length  of 
the  back-bone  and  of  the  arms,  in  various  races;  and 
nearly  all  these  measurements  show  that  the  males  differ 
much  more  from  one  another  than  do  the  females.  This 
fact  indicates  that,  as  far  as  these  characters  are  con- 
cerned, it  is  the  male  which  has  been  chiefly  modified, 
since  the  several  races  diverged  from  their  common  stock. 

The  development  of  the  beard  and  the  hairiness  of  the 
body  differ  remarkably  in  the  men  of  distinct  races,  and 
even  in  different  tribes  or  families  of  the  same  race.  We 
Europeans  see  this  among  ourselves.  In  the  Island  of  St. 
Kilda,  according  to  Martin,  f  the  men  do  not  acquire 
beards  until  the  age  of  thirty  or  upward,  and  even 
then  the  beards  are  very  thin.  On  the  Europseo- Asiatic 
continent,  beards  prevail  until  we  pass  beyond  India  ; 
though  with  the  natives  of  Ceylon  they  are  often  absent, 
as  was  noticed  in  ancient  times  by  Diodorus.J    Eastward 

*  The  results  were  deduced  by  Dr.  Weisbacli  from  the  measure- 
ments made  by  Drs.  K.  Scherzer  and  Schwarz.  See "  Reise  der 
•  Novara  :'  Antliropolog.  Theil,"  1867,  ss.  216,  231,  234,  236,  239,  269. 

\  "Voyage  to  St.  Kilda"  (3d  edit.,  1753),  p.  37. 

I  Sir  J.  E.  Tennent,  ♦'Ceylon,"  vol.  ii,  1859,  p.  107. 


SECONDARY  SEXUAL  CHARACTERS.  639 

of  India  beards  disappear,  as  with  the  Siamese,  Malays, 
Kahnucks,  Chinese,  and  Japanese;  nevertheless  the  Ainos,* 
who  inhabit  the  northernmost  islands  of  the  Japan  Archi- 
pelago, are  the  hairiest  men  in  the  world.  With  negroes 
the  beard  is  scanty  or  wanting,  and  they  rarely  have 
whiskers;  in  both  sexes  the  body  is  frequently  almost  des- 
titute of  fine  down.f  On  the  other  hand,  the  Papauns  of 
the  Malay  Archipelago,  who  are  nearly  as  black  as  negroes, 
possess  well-developed  beards.J  In  the  Pacific  Ocean  the 
inhabitants  of  the  Fiji  Archipelago  have  large  bushy 
beards,  while  those  of  the  not  distant  archipelagoes  of 
Tonga  and  Samoa  are  beardless;  but  these  men  belong  to 
distinct  races.  In  the  Ellice  group  all  the  inhabitants 
belong  to  the  same  race;  yet  on  one  island  alone,  namely 
Nunemaya,  *'  the  men  have  splendid  beards;  f  while  on 
the  other  islands  '^they  have,  as  a  rule,  a  dozen  straggling 
hairs  for  a  beard.  "§ 

Throughout  the  great  American  continent  the  men  may 
be  said  to  be  beardless;  but  in  almost  all  the  tribes  a  few 
short  hairs  are  apt  to  appear  on  the  face,  especially  in  old 
age.  With  the  tribes  of  North  America,  Catlin  estimates 
that  eighteen  out  of  twenty  men  are  completely  destitute 
by  nature  of  a  beard;  but  occasionally  there  may  be  seen  a 
a  man  who  has  neglected  to  pluck  out  the  hairs  at  puberty, 
with  a  soft  beard  an  inch  or  two  in  length.  The  Guaranys 
of  Paraguay  differ  from  all  the  surrounding  tribes  in  hav- 
ing a  small  beard,  and  even  some  hair  on  the  body,  but  no 
whiskers.  ||  I  am  informed  by  Mr.  D.  Forbes,  who  par- 
ticularly attended   to   this  point,   that  the  Aymaras  and 

* Quatref ages,  "Revue  des  Cours  Scientifiques,"  Aug.  29,  1868,  p. 
630;  Vogt,  "  Lectures  on  Man,"  Eng.  translat.,  p.  127. 

fOn  the  beards  of  negroes,  Vogt,  "  Lectures,"  etc.,  p.  127;  Waitz, 
'*  Introduct.  to  Anthropology,"  Eng.  translat.,  1863,  vol.  i,  p.  96.  It 
is  remarkable  that  in  the  United  States  ("  Investigations  in  Military 
and  Anthropological  Statistics  of  American  Soldiers,"  1869,  p.  569), 
the  pure  negroes  and  their  crossed  offspring  seem  to  have  bodies 
almost  as  hairy  as  Europeans. 

t  Wallace.  "  The  Malay  Arch.,"  vol.  ii,  1869,  p.  178. 

gDr.  J.  Barnard  Davis  on  "Oceanic  Races,"  in  "  Antbropolog. 
Review,"  April,  1870,  pp.  185,  191. 

I  Catlin,  "  North  American  Indians,"  3d  edit.,  1842,  vol.  ii,  p.  227. 
On  the  Guaranys,  see  Azara,  "  Voyages  dans  I'Amerique  Merid.," 
torn,  ii.,  1609,  p.  ^\  also  Rengger,  "  Saugethiere  von  Paraguay," 
B.  3. 


640  TUK  DESCENT  OF  MAN. 

Quicliuas  of  the  Cordillera  are  remarkably  hairless,  yet  in 
old  age  a  few  straggling  hairs  occasionally  a})pear  on  the 
chin.  The  men  of  these  two  tribes  have  very  little  hair  on 
the  various  parts  of  the  body  where  hair  grows  abundantly 
in  Europeans,  and  the  women  have  none  on  the  corre- 
sponding parts.  The  hair  on  the  head,  however,  attains 
an  extraordinary  length  in  both  sexes,  often  reaching 
almost  to  the  ground;  and  this  is  likewise  the  case  with 
some  of  the  North  American  tribes.  In  the  amount  of  hair 
and  in  the  general  shape  of  the  body  the  sexes  of  the 
American  aborigines  do  not  differ  so  much  from  each  other 
as  in  most  other  races.*  This  fact  is  analogous  with  what 
occurs  with  some  closely  allied  monkeys;  thus  the  sexes  of 
the  chimpanzee  are  not  as  different  as  those  of  the  orang 
or  gorilla,  t 

In  the  previous  chapters  we  have  seen  that  with  mam- 
mals, birds,  fishes,  insects,  etc.,  many  characters,  which 
there  is  every  reason  to  believe  were  primarily  gained 
through  sexual  selection  by  one  sex,  have  been  transferred 
to  the  other.  As  this  same  form  of  transmission  has  ap- 
parently prevailed  much  with  mankind,  it  will  save  useless 
repetition  if  we  discuss  the  origin  of  characters  peculiar  to 
the  male  sex  together  with  certain  other  characters  com- 
mon to  both  sexes. 

Law  of  Battle. — With  savages,  for  instance,  the  Aus- 
tralians, the  women  are  the  constant  cause  of  war  both 
between  members  of  the  same  tribe  and  between  distinct 
tribes.  So  no  doubt  it  was  in  ancient  times;  ' '  nam  f uit  ante 
Helenam  mulier  teterrima  belli  causa.  ^^  With  some  of  the 
North  American  Indians  the  contest  is  reduced  to  a  system. 
That  excellent  observer,  Hearne,J;  says:  '*It  has  ever 
been  the  custom  among  these  people  for  the  men  to  wrestle 

*Prof.  and  Mrs.  Agassiz  ("Journey  in  Brazil,"  p.  530),  remark 
that  the  sexes  of  the  American  Indians  differ  less  than  those  of  the 
negroes  and  of  the  higher  races.  See  also  Rengger,  ibid.,  p.  3,  on 
the  Guaranys. 

f  Riitimeyer,  "  Die  Grenzen  der  Thierwelt;  eine  Betrachtung  zu 
Darwin's  Lehre,"  1868,  s.  54. 

:j: "  A  Journey  from  Prince  of  Wales  Fort.,"  Svo.  edit.,  Dublin, 
1796,  p.  104.  Sir  J.  Lubbock  ("  Origin  of  Civilization,"  1870,  p.  69), 
gives  other  and  similar  cases  in  North  America.  For  the  Guanas  of 
South  America  see  Azara,  "Voyages,"  etc.,  torn,  ii,  p.  94. 


SECONDARY  SEXUAL  CHARACTERS.  641 

for  any  woman  to  whom  they  are  attached;  and,  of  course, 
the  strongest  party  always  carries  off  the  prize.  A  weak  man, 
unless  he  be  a  good  hunter  and  well  beloved,  is  seldom  per- 
mitted to  keep  a  wife  that  a  stronger  man  thinks  worth  his 
notice.  This  custom  prevails  throughout  all  the  tribes, 
and  causes  a  great  spirit  of  emulation  among  their  youth, 
who  are  upon  all  occasions,  from  their  childhood,  trying 
their  strength  and  skill  in  wrestling."  With  the  Guanas 
of  South  America,  Azara  states  that  the  men  rarely  marry 
till  twenty  years  old  or  more,  as  before  that  age  they  cannot 
conquer  their  rivals. 

Other  similar  facts  could  be  given;  but  even  if  we  had 
no  evidence  on  this  head  we  might  feel  almost  sure,  from 
the  analogy  of  the  higher  Quadrumana,*  that  the  law  of 
battle  had  prevailed  with  man  during  the  early  stages  of 
his  development.  The  occasional  appearance  at  the  pres- 
ent day  of  canine  teeth  which  project  above  the  others, 
with  traces  of  a  diastema  or  open  space  for  the  reception  of 
the  opposite  canines,  is  in  all  probability  a  case  of  reversion  to 
a  former  state,  when  the  progenitors  of  man  were  provided 
Avith  these  weapons,  like  so  many  existing  male  Quadrumana. 
It  was  remarked  in  a  former  chapter  that  as  man  gradually 
became  erect,  and  continually  used  his  hands  and  arms 
for  fighting  with  sticks  and  stones,  as  well  as  for  the  other 
purposes  of  life,  he  would  have  used  his  jaws  and  teeth 
less  and  less.  The  jaws,  together  with  their  muscles,  would 
then  have  been  reduced  through  disuse,  as  would  the  teeth 
through  the  not  well  understood  principles  of  correlation 
and  economy  of  growth;  for  we  everywhere  see  that  parts, 
which  are  no  longer  of  service,  are  reduced  in  size.  By  such 
steps  the  original  inequality  between  the  jaws  and  teeth 
in  the  two  sexes  of  mankind  would  ultimately  have  been 
obliterated.  The  case  is  almost  parallel  with  that  of  many 
male  ruminants,  in  which  the  canine  teeth  have  been- 
reduced  to  mere  rudiments,  or  have  disappeared,  apparently, 
in  consequence  of  the  development  of  horns.  As  the  prodig- 
ious difference  between  the  skulls  of  the  two  sexes  in  the 
orang  and  gorilla  stands  in  close  relation  with  the  develop- 
ment of  the  immense  canine  teeth  in  the  males,  we  may 
infer  that  the  reduction  of  the  jaws  and  teeth  in  the  early 

♦On  the  fighting  of  the  male  gorillas,  see  Dr.  Savage,  in  " Boston 
Journal  of  Nat.  Hist.,"  vol  v.,  1847,  p.  423.  On  PrefbytU  enteUus, 
eee  the  "  Indian  Field,"  1859,  p.  146. 


642  THE  DESCENT  OF  MAN. 

male  progenitors  of  man  must  have  led  to  a  most  striking 
and  favorable  change  in  his  appearance. 

There  can  be  little  doubt  that  the  greater  size  and 
strength  of  man,  in  comparison  with  woman,  together  with 
his  broader  shoulders,  more  developed  muscles,  rugged  out- 
line of  body,  his  greater  courage  and  pugnacity  are  all  due 
in  chief  part  to  inheritance  from  his  ha^f- human  male  ances- 
tors. These  characters  would,  however,  have  been  preserved 
or  even  augmented  during  the  long  ages  of  man's  savagery, 
by  the  success  of  the  strongest  and  boldest  men,  both  in  the 
general  struggle  for  life  and  in  their  contests  for  wives;  a  suc- 
cess which  would  have  insured  tlieir  leaving  a  more  numer- 
ous progeny  than  their  less  favored  brethren.  It  is  not  proba- 
ble that  the  greater  strength  of  man  was  primarily  acquired 
through  the  inherited  effects  of  his  having  worked  harder 
than  woman  for  his  own  subsistence  and  that  of  his  family; 
for  the  women  in  all  barbarous  nations  are  compelled 
to  work  at  least  as  hard  as  the  men.  With  civilized 
people  the  arbitrament  of  battle  for  the  possession  of  the 
women  has  long  ceased;  on  the  other  hand,  the  men,  as  a 
general  rule,  have  to  work  harder  than  the  women  for  tlieir 
joint  subsistence,  and  thus  their  greater  strength  will  have 
been  kept  up. 

Difference  in  the  Mental  Poioers  of  the  Two  Sexes. — With 
respect  to  differences  of  this  nature  between  man  and 
woman  it  is  probable  that  sexual  selection  has  played  a 
highly  important  part.  I  am  aware  that  some  writers 
doubt  whether  there  is  any  such  inherent  differerice ;  but 
this  is  at  least  probable  from  the  analogy  of  the  lower  ani- 
mals which  present  other  secondary  sexual  characters.  No 
one  disputes  that  the  bull  differs  in  disposition  from  the 
cow,  the  wild-boar  from  the  sow,  the  stallion  from  the 
mare,  and,  as  is  well  known  to  the  keepers  of  menageries, 
the  males  of  the  larger  apes  from  the  females.  Woman 
seems  to  differ  from  man  in  mental  disposition,  chiefly  in 
her  greater  tenderness  and  less  selfishness;  and  this  holds 
^ood  even  with  savages,  as  shown  by  a  well-known  passage 
m  "  Mungo  Park's  Travels,"'  and  by  statements  made  by 
many  other  travelers.  Woman,  owing  to  her  maternal 
instincts,  displays  these  qualities  toward  her  infant  in  an 
eminent  degree;  therefore  it  is  likely  that  she  would  often 
extend  them  toward  her  fellow-creatures,    Man  is  the  rival 


SECONDARY  SEXUAL  CHABAGTERS.  643 

of  other  men;  lie  delights  in  competition,  and  this  leads  to 
ambition  which  passes  too  easily  into  selfishness.  These 
latter  qualities  seem  to  be  his  natural  and  unfortunate 
birthright.  It  is  generally  admitted  that  with  woman  the 
powers  of  intuition,  of  rapid  perception,  and  perhaps  of 
imitation,  are  more  strongly  marked  than  in  man;  but 
some,  at  least,  of  these  faculties  are  characteristic  of  the 
lower  races,  and,  therefore,  of  a  past  and  lower  state  of 
civilization. 

The  chief  distinction  in  the  intellectual  powers  of  the 
two  sexes  is  shown  by  man's  attaining  to  a  higher  eminence, 
in  whatever  he  takes  up,  than  can  woman — w^hether  requir- 
ing deep  thought,  reason,  or  imagination,  or  merely  the 
use  of  the  senses  and  hands.  If  two  lists  were  made  of  the 
most  eminent  men  and  women  in  poetry,  painting,  sculpt- 
ure, music  (inclusive  both  of  composition  and  perform- 
ance), history,  science  and  philosophy,  with  half  a  dozen 
names  under  each  subject,  the  two  lists  would  not  bear 
comparison.  We  may  also  infer,  from  the  law  of  the  devia- 
tion from  averages,  so  well  illustrated  by  Mr.  Galton,  in 
his  work  on  "  Hereditary  Genius, ''  that  if  men  are  capable 
of  a  decided  pre-eminence  over  women  in  many  subjects, 
the  average  of  mental  power  in  man  must  be  above  that  of 
woman. 

Among  the  half -human  progenitors  of  man,  and  among 
savages,  there  have  been  struggles  between  the  males  during 
many  generations  for  the  possession  of  the  females.  But 
mere  bodily  strength  and  size  would  do  little  for  victory, 
unless  associated  with  courage,  perseverence  and  deter- 
mined energy.  With  social  animals  the  young  males  have 
to  pass  through  many  a  contest  before  they  win  a  female, 
and  the  older  males  have  to  retain  their  females  by  renewed 
battles.  They  have,  also,  in  the  case  of  mankind,  to 
defend  their  females,  as  well  as  their  young,  from  enemies 
of  all  kinds,  and  to  hunt  for  their  joint  subsistence.  But 
to  avoid  enemies  or  to  attack  them  with  success,  to  capture 
wild  animals,  and  to  fashion  weapons,  requires  the  aid  of 
the  higher  mental  faculties,  namely,  observation,  reason, 
invention,  or  imagination.  These  various  faculties  will 
thus  have  been  continually  put  to  the  test  and  selected 
during  manhood;  they  will,  moreover,  have  been  strength- 
ened by  use  during  this  same  period  of  life.  Consequently, 
in  accordance  with  the  principle  often  alluded  to,  we 


644  THE  DESCENT  OF  MAN. 

might  expect  that  they  would  at  least  tend  to  be  trans- 
mitted chiefly  to  the  male  offspring  at  the  corresponding 
period  of  manhood. 

\^ow,  when  two  men  are  put  into  competition,  or  a  man 
with  a  woman,  both  possessed  of  every  mental  quality  in 
equal  perfection,  save  that  one  has  higher  energy,  perse- 
verance and  courage,  the  latter  will  generally  become  more 
eminent  in  every  i)ursuit  and  will  gain  the  ascendency.* 
lie  may  be  said  to  possess  genius — for  genius  has  been  de- 
clared by  a  great  authority  to  be  patience;  and  patience,  in 
this  sense,  means  unflinching,  undaunted  perseverance. 
But  this  view  of  genius  is  perhaps  deficient;  for  without 
the  higher  powers  of  the  imagination  and  reason,  no 
eminent  success  can  be  gained  in  many  subjects.  These 
latter  faculties,  as  well  as  the  former,  will  have  been  de- 
iVeloped  in  man,  partly  through  sexual  selection — that  is, 
^through  the  contest  of  rival  males,  and  partly  through 
natural  selection — that  is,  from  success  in  the  general 
struggle  for  life;  and  as  in  both  cases  the  struggle  will  have 
been  during  maturity,  the  characters  gained  will  have  been 
/  transmitted  more  fully  to  the  male  than  to  the  female  off- 
spring?) It  accords  in  a  striking  manner  with  this  view  of 
the  modification  and  re-enforcement  of  many  of  our 
mental  faculties  by  sexual  selection,  that,  firstly,  they 
notoriously  undergo  a  considerable  change  at  puberty,! 
and,  secondly,  that  eunuchs  remain  throughout  life  inferior 
in  these  same  qualities.  Thus  man  has  ultimately  become 
superior  to  w^oman.  It  is,  indeed,  fortunate  that  the  law 
of  the  equal  transmission  of  characters  to  both  sexes  pre- 
vails with  mammals ;  otherwise  it  is  probable  that  man 
would  have  become  as  superior  in  mental  endowment  to 
woman,  as  the  peacock  is  in  ornamental  plumage  to  the 
peahen. 

It  must  be  borne  in  mind  that  the  tendency  in  char- 
acters acquired  by  either  sex  late  in  life,  to  be  transmitted 
to  the  same  sex  at  the  same  age,  and  of  early  acquired 
characters  to  be  transmitted  to  both  sexes,  are  rules  which, 
though  general,  do  not  always  hold.     If  they  always  held 

*J.  Stuart  Mill  remarks  ("  The  Subjection  of  Women,"  1869,  p. 
122);  '  The  things  in  which  man  most  excels  woman  are  those  which 
require  most  plodding,  and  long  hammering  at  single  thoughts." 
What  is  this  but  energy  and  perseverance? 

f  Maudsley,  "  Mind  and  Body,"  p.  31. 


SECONDARY  SEXUAL  CEARACTEUS.  645 

good,  we  might  conclude  (but  I  here  exceed  my  proper 
bounds)  that  the  inlierited  effects  of  the  early  education  of 
boys  and  girls  would  be  transmitted  equally  to  both  sexes; 
so  that  the  present  inequality  in  mental  power  between  the 
sexes  would  not  be  effaced  by  a  similar  course  of  early 
training;  nor  can  it  have  been  caused  by  their  dissimilar 
early  training.  In  order  that  woman  should  reach  the 
same  standard  as  man,  she  ought,  when  nearly  adult,  to  be 
trained  to  energy  and  perseverance  and  to  have  her  reason 
and  imagination  exercised  to  the  highest  point;  and  then 
she  would  probably  transmit  these  qualities  chiefly  to  her 
adult  daughters.  All  women,  however,  could  not  be  thus 
raised,  unless  during  many  generations  those  who  excelled 
in  the  above  robust  virtues  were  married  and  produced  off- 
spring in  larger  numbers  than  other  women.  As  before 
remarked  of  bodily  strength,  although  men  do  not  now 
fight  for  their  wives,  and  this  form  of  selection  has  passed 
away,  yet  during  manhood  they  generally  undergo  a  severe 
struggle  in  order  to  maintain  themselves  and  their  families; 
and  this  will  tend  to  keep  up  or  even  increase  their  mental 
powers,  and,  as  a  consequence,  the  present  inequality  be- 
tween the  sexes.* 

Voice  and  Musical  Poivers. — In  some  species  of  Quadru- 
mana  there  is  a  great  difference  between  the  adult  sexes, 
in  the  power  of  their  voices  and  in  the  development  of 
the  vocal  organs;  and  man  appears  to  have  inherited  this 
difference  from  liis  early  progenitors.  His  vocal  cords  are 
about  one-third  longer  than  in  woman,  or  than  in  boys  ; 
and  emasculation  produces  the  same  effect  on  him  as  on 
the  lower  animals,  for  it  '^  arrests  that  prominent  growth  of 
the  thyroid,  etc.,  which  accompanies  the  elongation  of  the 
cords. '^t  With  respect  to  the  cause  of  this  difference 
between  the  sexes,  I  have  nothing  to  add  to  the  remarks  in 

*  An  observation  by  Vogt  bears  on  tbis  subject:  he  says,  "  It  is  a 
remarkable  circumstance,  that  the  differences  between  the  sexes,  as 
regards  the  cranial  cavity,  increases  with  the  development  of  the 
race,  so  that  the  male  European  excels  much  more  the  female,  than 
the  negro  the  negress.  Welcker  confirms  this  statement  of  Huschke 
from  his  measurements  of  negro  and  German  skulls."  But  Vogt 
admits  ("Lectures  on  Man,"  Eng.  translat.,  1864,  p.  81)  that  more 
observations  are  requisite  on  this  point. 

f  Owen,  "Anatomy  of  Vertebrates,"  vol.  iii,  p.  603. 


C46  1'JJJ^  DESCENT  OF  MAN. 

the  last  chapter  on  tlie  probable  effects  of  the  long-contin- 
ued use  of  the  vocal  organs  by  the  male  under  the  excite- 
ment of  love,  rage  and  jealousy.  According  to  Sir  Duncan 
(ribb,*  the  voice  and  the  form  of  the  larynx  differ  in  the 
different  races  of  mankind;  but  with  the  Tartars,  Chinese, 
etc.,  the  voice  of  the  male  is  said  not  to  differ  so  much 
from  that  of  the  female,  as  in  most  other  races. 

The  capacity  and  love  for  singing  or  music,  though  not 
a  sexual  character  in  man,  must  not  here  be  passsd  over. 
Although  the  sounds  emitted  by  animals  of  all  kinds 
serve  many  purposes,  a  strong  case  can  be  made  out,  that 
the  vocal  organs  were  primarily  used  and  perfected  in  rela- 
tion to  the  propagation  of  the  species.  Insects  and  some 
few  spiders  are  the  lowest  animals  which  voluntarily  pro- 
duce any  sound;  and  this  is  generally  effected  by  the  aid  of 
beautifully  constructed  stridulating  organs,  which  are  often 
confined  to  the  males.  The  sounds  thus  produced  consist, 
I  believe  in  all  cases,  of  the  same  note,  repeated  rhythmi- 
cally;! and  this  is  sometimes  pleasing  even  to  the  ears  of 
man.  The  chief  and,  in  some  cases,  exclusive  purpose 
appears  to  be  either  to  call  or  charm  the  opposite  sex. 

The  sounds  produced  by  fishes  are  said  in  some  cases  to 
be  made  only  by  the  males  during  the  breeding-season.  All 
the  air-breathing  Vertebrata  necessarily  possess  an  appa- 
ratus for  inhaling  and  expelling  air,  with  a  pipe  capable  of 
being  closed  at  one  end.  Hence  when  the  primeval  mem- 
bers of  this  class  were  strongly  excited  and  their  muscles 
violently  contracted,  purposeless  sounds  would  almost  cer- 
tainly have  been  produced;  and  these,  if  they  proved  in 
any  way  serviceable,  might  readily  have  been  modified  or 
intensified  by  the  preservation  of  properly  adapted  vari- 
ations. The  lowest  Vertebrates  which  breathe  air  are 
Amphibians;  and  of  these,  frogs  and  toads  possess  vocal 
organs,  which  are  incessantly  used  during  the  breeding- 
season,  and  which  are  often  more  highly  developed  in  the 
male  than  in  the  female.  The  male  alone  of  the  tortoise 
utters  a  noise,  and  this  only  during  the  season  of  love. 
Male  alligators  roar  or  bellow  during  the  same  season. 
Every  one  knows  how  much  birds  use  their  vocal  organs  as 

*"  Jouraal  of  the  Anthropolog.  Soc,"  April,  1869,  pp.  57,  66. 
f  Dr.  Scudder,  "  Notes  on  Stridulation,"  in  "  Proc.  Boston  Soc.  of 
Nat.  Hist.,"  vol.  xi,  April,  1868. 


BBCONDAR  Y  SEXUA  L  Off  A  RACTEHS.  64^ 

a  means  of  courtship;  and  some  species  likewise  perform 
what  may  be  called  instrumental  music. 

In  the  class  of  mammals,  with  which  we  are  here  more 
particularly  concerned,  the  males  of  almost  all  the  species 
use  their  voices  during  the  breeding-season  much  more 
than  at  any  other  time  ;  and  some  are  absohitely  mute 
excepting  at  this  season.  With  other  species  both  sexes, 
or  only  the  females,  use  their  voices  as  a  love-call.  Con- 
sidering these  facts,  and  that  the  vocal  organs  of  some 
quadrupeds  are  much  more  largely  developed  in  the  male 
than  in  the  female,  either  permanently  or  temporarily, 
during  the  breeding-season;  and  considering  that  in  most 
of  the  lower  classes  the  sounds  produced  by  the  males  serve 
not  only  to  call  but  to  excite  or  allure  the  female;  it  is  a 
surprising  fact  that  we  have  not  as  yet  any  good  evidence 
that  these  organs  are  used  by  male  mammals  to  charm  the 
females.  The  American  Mycetes  caraya  perhaps  forms  an 
exception,  as  does  the  Hylohates  agilis,  an  ape  allied  to 
man.  This  gibbon  has  an  extremely  loud  but  musical 
voice.  Mr.  AVaterhouse  states,*  "  It  appeared  to  me  that 
in  ascending  and  descending  the  scale  the  intervals  were 
always  exactly  half-tones;  and  I  am  sure  that  the  highest 
note  was  the  exact  octave  to  the  lowest.  The  quality  of  the 
notes  is  very  musical;  and  I  do  not  doubt  that  a  good 
violinist  would  be  able  to  give  a  correct  idea  of  the  gibbon's 
composition,  excepting  as  regards  its  loudness."  Mr. 
Waterhouse  then  gives  the  notes.  Prof.  Owen,  who  is  a 
musician,  confirms  the  foregoing  statement,  and  remarks, 
though  erroneously,  that  this  gibbon,  "alone  of  brute 
mammals,  may  be  said  to  sing."  It  appears  to  be  much 
excited  after  its  performance.  Unfortunately,  its  habits 
have  never  been  closely  observed  in  a  state  of  nature;  but 
from  the  analogy  of  other  animals,  it  is  probable  that  it 
uses  its  musical  powers  more  especially  during  the  season 
of  courtship. 

This  gibbon  is  not  the  only  species  in  the  genus  which 
sings,  for  my  son,  Francis  Darwin,  attentively  listened  in 
the  Zoological  Gardens  to  H.  leuciscus  while  singing  a 
cadence  of  three  notes,  in  true  musical  intervals  and  with 
a  clear  musical  tone.     It  is  a  more  surprising  fact  that 

♦Given  in  W.  C.  L.  Martin's  "  General  Intrckluction  to  Nat.  Hist, 
of  Mamm.  Animals,"  1841,  p.  432;  Owen  '  Anatomy  of  Vertebrates," 
vol.  iii,  p.  600. 


C48  ^^^  DESCENT  OF  MAN. 

certain  rodents  ntter  musical  sounds.  Singing  mice  have 
often  been  mentioned  and  exliibited,  but  imposture  has 
commonly  been  suspected.  We  have,  however,  at  last  a 
clear  account  by  a  well-known  observer,  tlie  Rev.  S.  Lock- 
wood,*  of  the  musical  powers  of  an  American  species,  tlie 
Hesperornys  cognatiis,  belonging  to  a  genus  distinct  from 
that  of  the  English  mouse.  This  little  animal  was  kept  in 
confinement,  and  the  performance  was  repeatedly  heard. 
In  one  of  the  two  cliief  songs,  "  the  last  bar  would  fre- 
quently be  prolonged  to  two  or  three;  and  slie  would  some- 
times change  from  C  sharp  and  D  to  C  natural  and  D,  then 
warble  on  these  two  notes  awhile,  and  wind  up  with  a  quick 
chirp  on  C  sharp  and  D.  The  distinctness  between  the 
semitones  was  very  marked  and  easily  appreciable  to  a 
good  ear."  Mr.  Lockwood  gives  both  songs  in  musical 
notation;  and  adds  that  though  this  little  mouse  *^had  no 
ear  for  time,  yet  she  would  keep  to  the  key  of  B  (two  flats) 
and  strictly  in  a  major  key.  .  .  .  Her  soft  clear 
voice  falls  an  octave  with  all  the  precision  possible;  then  at 
the  wind-up  it  rises  again  into  a  quick  thrill  on  0  sharp 
and  D." 

A  critic  has  asked  how  the  ears  of  man,  and  he  ought  to 
have  added  of  other  animals,  could  have  been  adapted  by 
selection  so  as  to  distinguish  musical  notes.  But  this 
question  shows  some  confusion  on  the  subject;  a  noise  is  the 
sensation  resulting  from  the  co-existence  of  several  aerial 
"simple  vibrations"  of  various  periods,  each  of  which 
intermits  so  frequently  that  its  separate  existence  cannot  be 
perceived.  It  is  only  in  the  want  of  continuity  of  such 
vibrations,  and  in  their  want  of  harmony  inter  se,  that  a  noise 
differs  from  a  musical  note.  Thus  an  ear  to  be  capable  of 
discriminating  noises — and  the  high  importance  of  this 
power  to  all  animals  is  admitted  by  every  one — must  be 
sensitive  to  musical  notes.  We  have  evidence  of  this 
capacity  even  low  down  in  the  animal  scale;  thus  Crusta- 
ceans are  provided  with  auditory  hairs  of  different  lengths, 
which  have  been  seen  to  vibrate  when  the  proper  musical 
notes  are  struck,  f  As  stated  in  a  previous  chapter,  similar 
observations  have  been  made  on  the  hairs  of  the  antennae 
of  gnats.     It  has  been  positively  asserted  by  good  observers 

*Tlie  "American  Naturalist,"  1871.  p.  761. 

f  Helmlioltz,  "  Theorie  Phys.  de  la  Musique,"  1868,  p.  187. 


SECONDARY  SEXUAL  CHARACTERS.  649 

that  spiders  are  attracted  by  music.  It  is  also  well  known 
that  some  dogs  howl  when  hearing  particular  tones.*  Seals 
apparently  appreciate  music,  and  their  fondness  for  it 
"  was  well  known  to  the  ancients,  and  is  often  taken 
advantage  of  by  the  hunters  at  the  present  day.^f 

Therefore,  as  far  as  the  mere  perception  of  musical 
notes  is  concerned,  there  seems  no  special  difficulty  in  the 
case  of  man  or  of  any  other  animal.  Helmholtz  has  explained 
on  physiological  principles  why  concords  are  agreeable  and 
discords  disagreeable  to  the  human  ear;  but  we  are  little 
concerned  with  these,  as  music  in  harmony  is  a  late  inven- 
tion. We  are  more  concerned  with  melody,  and  here 
again,  according  to  Helmholtz,  it  is  intelligible  why  the 
notes  of  our  musical  scale  are  used.  The  ear  analyzes  all 
sounds  into  their  component  "  simple  vibrations,"  although 
we  are  not  conscious  of  this  analysis.  In  a  musical  note 
the  lowest  in  pitch  of  these  is  generally  predominant,  and 
the  others  which  are  less  marked  are  the  octave,  the 
twelfth,  the  second  octave,  etc.,  all  harmonies  of  the 
fundamental  predominant  note;  any  two  notes  of  our  scale 
have  many  of  these  harmonic  over-tones  in  common.  It 
seems  pretty  clear,  then,  that  if  an  animal  always  wished 
to  sing  precisely  the  same  song,  he  would  guide  himself  by 
sounding  those  notes  in  succession  which  possess  many 
over-tones  in  common — that  is,  he  would  choose  for  his 
song  notes  which  belong  to  our  musical  scale. 

But  if  it  be  further  asked  why  musical  tones  in  a  certain 
order  and  rhythm  give  man  and  other  animals  pleasure,  we 
can  no  more  give  the  reason  than  for  the  pleasantness  of 
certain  tastes  and  smells.  That  they  do  give  pleasure  of 
some  kind  to  animals  we  may  infer  from  their  being  pro- 
duced during  the  season  of  courtship  by  many  insects, 
spiders,  fishes,  amphibians  and  birds ;  for  unless  the 
females  were  able  to  appreciate  such  sounds  and  were 
excited  or  charmed  by  them,  the  persevering  efforts  of  the 
males,  and  the  complex  structures  often  possessed  by  them 
alone,  would  be  useless ;  and  this  it  is  impossible  to 
believe. 

*  Several  accounts  have  been  published  to  tins  effect.  Mr.  Peach 
writes  to  me  that  be  bas  repeatedly  found  tbat  an  old  dog  of  bis 
bowls  wben  B  flat  is  sounded  on  tbe  flute,  and  to  no  other  note.  I 
may  add  anotber  instance  of  a  dof^  always  wbining,  wben  one  note 
on  a  concertina,  wbich  was  out  of  tune,  was  played. 

f  Mr.  R.  Brown,  in  ''Proc.  Zool.  Soc,"  1868,  p.  410. 


650  THE  DESCENT  OF  MAN. 

Human  song  is  generally  admitted  to  be  the  basis  or 
origin  of  instrumental  music.  As  neither  the  enjoyment 
nor  the  capacity  of  producing  musical  notes  are  faculties 
of  the  least  use  to  man  in  reference  to  his  daily  habits  of 
life,  they  must  be  ranked  among  the  most  mysterious  with 
which  he  is  endowed.  Tliey  are  present,  though  in  a  very 
rude  condition,  in  men  of  all  races,  even  the  most  savage; 
but  so  different  is  the  taste  of  the  several  races  that  our 
music  gives  no  pleasure  to  savages,  and  their  music  is  to  us 
in  most  cases  hideous  and  unmeaning.  Dr.  Seemann,  in 
some  interesting  remarks  on  this  subject,*  ^'  doubts 
whether  even  among  the  nations  of  Western  Europe, 
intimately  connected  as  they  are  by  close  and  frequent 
intercourse,  the  music  of  the  one  is  interpreted  in  the  same 
sense  by  the  others.  By  traveling  eastward  we  find  that 
there  is  certainly  a  different  language  of  music.  Songs  of 
joy  and  dance  accompaniments  are  no  longer,  as  with  us, 
in  the  major  keys,  but  always  in  the  minor."  Whether  or 
not  the  half -human  progenitors  of  man  possessed,  like  the 
singing  gibbons,  the  capacity  of  producing,  and,  therefore, 
no  doubt  of  appreciating,  musical  notes,  we  know  that 
man  possessed  these  faculties  at  a  very  remote  period.  M. 
Lartet  has  described  two  flutes  made  out  of  the  bones  and 
horns  of  the  reindeer,  found  in  caves  together  with  flint 
tools  and  the  remains  of  extinct  animals.  The  arts  of 
singing  and  of  dancing  are  also  very  ancient,  and  are  now 
practiced  by  all  or  nearly  all  the  lowest  races  of  man. 
Poetry,  which  may  be  considered  as  the  offspring  of  song, 
is  likewise  so  ancient  that  many  persons  have  felt  astonished 
that  it  should  have  arisen  during  the  earliest  ages  of  which 
we  have  any  record. 

We  see  that  the  musical  faculties,  which  are  not  wholly 
deficient  in  any  race,  are  capable  of  prompt  and  high 
development,  for  Hottentots  and  negroes  have  become 
excellent  musicians,  although  in  their  native  countries 
they  rarely  practice  anything  that  we  should  consider 
music.  Schweinfurth,  however,  was  pleased  with  some  of 
the  simple  melodies  which  he  heard  in  the  interior  of 
Africa.     But  there  is  nothing  anomalous  in  the  musical 

*  "Journal  of  Anthropolog.  Soc,"  Oct.,  1870,  p.  155.  See  also  the 
several  later  chapters  in  Sir  John  Lubbock's  "  Prehistoric  Times," 
second  edition,  1869,  which  contain  an  admirable  account  of  the 
habits  of  savages. 


Secondary  sexual  cSahactbbs.         651 

facilities  lying  dormant  in  man;  some  species  of  birds 
which  never  naturally  sing,  can  without  much  difficulty  be 
taught  to  do  so;  thus  a  house-sparrow  has  learned  the  song 
of  a  linnet.  As  these  two  species  are  closely  allied  and 
belong  to  the  order  of  Insessores,  which  includes  nearly  all 
the  singing-birds  in  the  world,  it  is  possible  that  a  pro- 
genitor of  the  sparrow  may  have  been  a  songster.  It  is 
more  remarkable  that  parrots,  belonging  to  a  group  distinct 
from  the  Insessores,  and  having  differently  constructed 
vocal  organs,  can  be  taught  not  only  to  speak,  but  to  pipe 
or  whistle  tunes  invented  by  man,  so  that  they  must  have 
some  musical  capacity.  Nevertheless,  it  would  be  very  rash 
to  assume  that  parrots  are  descended  from  some  ancient 
form  which  was  a  songster.  Many  cases  could  be  advanced 
of  organs  and  instincts  originally  adapted  for  one  purpose, 
having  been  utilized  for  some  distinct  pui-pose.*  Hence 
the  capacity  for  high  musical  development  which  the 
savage  races  of  man  possess,  may  be  due  either  to  the  prac- 
tice by  our  semi-human  progenitors  of  some  rude  form  of 
music,  or  simply  to  their  having  acquired  the  proper  vocal 
organs  for  a  diiTerent  purpose.  But  in  this  latter  case  we 
must  assume,  as  in  the  above  instance  of  parrots,  and  as 
seems  to  occur  with  many  animals,  that  they  already  pos- 
sessed some  sense  of  melody. 

Music  arouses  in  us  various  emotions,  but  not  the  more 
terrible  ones  of  horror,  fear,  rage,  etc.  It  awakens  the 
gentler  feelings  of  tenderness  and  love,  which  readily  pass 
into  devotion.  In  the  Chinese  annals  it  is  said:  '^  Music 
hath  the  power  for  making  heaven  descend  upon  earth." 
It  likewise  stirs  up  in  us  the  sense  of  triumph  and  the 
glorious  ardor  for  war.  These  powerful  and  mingled  feel- 
ings may  well  give  rise  to  the  seijse  of  sublimity.  We  can 
concentrate,  as  Dr.  Seeman  observes,  greater  intensity  of 
feeling  in  a  single  musical  note  than  in  pages  of  writing. 

*  Since  this  chapter  was  printed,  I  have  seen  a  valuable  article  by 
Mr.  Chauncy  Wright  ("  North  American  Review,"  Oct.,  1870,  p. 
293),  who,  in  discussing  the  above  subject,  remarks:  *' There  are 
many  consequences  of  the  ultimate  laws  or  uniformities  of  nature, 
through  which  the  acquisition  of  one  useful  power  will  bring  with  it 
many  resulting  advantages  as  well  as  limiting  disadvantages,  actual 
or  possible,  which  the  principle  of  utility  may  not  have  com])rehended 
in  its  actions."  As  I  have  attempted  to  show  in  an  early  chapter  of 
this  work,  this  principle  has  an  iinptirtant  l)eariug  on  the  acquisition 
by  man  of  some  of  his  mental  characteristics. 


652  THE  DESCENT  OF  MAN. 

It  is  probable  that  nearly  the  same  emotions,  but  much 
weaker  and  far  less  complex,  are  felt  by  birds  when  the 
male  pours  forth  his  full  volume  of  song,  in  rivalry  with 
other  males,  to  captivate  the  female.  Love  is  still  the 
commonest  theme  of  our  songs.  As  Herbert  Spencer  re- 
marks, "  music  arouses  dormant  sentiments  of  which  we 
had  not  conceived  the  possibility,  and  do  not  know  the 
meaning;  or,  as  Richter  says,  tells  us  of  things  we  have  not 
seen  and  shall  not  see."  Conversely,  when  vivid  emotions 
are  felt  and  expressed  by  the  orator,  or  even  in  common 
speech,  musical  cadences  and  rhythm  are  instictively  used. 
The  negro  in  Africa  when  excited  often  bursts  forth  in 
song;  ^^  another  will  reply  in  song,  while  the  company,  as 
if  touched  by  a  musical  wave,  murmur  a  chorus  in  perfect 
unison."*  Even  monkeys  express  strong  feelings  in  dif- 
ferent tones — anger  and  impatience  by  low,  fear  and  pain 
by  high  notes.  \  The  sensations  and  ideas  thus  excited  in 
us  by  music,  or  expressed  by  the  cadences  of  oratory,  appear 
from  their  vagueness,  yet  depth,  like  mental  reversions  to 
the  emotions  and  thoughts  of  a  long  past  age. 

All  these  facts  witli  respect  to  music  and  impassioned 
speech  become  intelligible  to  a  certain  extent,  if  we  may 
assume  that  musical  tones  and  rhythm  were  used  by  our 
half-human  ancestors,  during  the  season  of  courtship, 
when  animals  of  all  kinds  are  excited  not  only  by  love,  but 
by  the  strong  passions  of  jealousy,  rivalry,  and  triumph. 
From  the  deeply  laid  principle  of  inherited  associations, 
musical  tones  in  this  case  would  be  likely  to  call  up 
vaguely  and  indefinitely  the  strong  emotions  of  a  long-past 
age.  As  we  have  every  reason  to  suppose  that  articulate 
speech  is  one  of  the  latest,  as  it  certainly  is  the  highest,  of 
the  arts  acquired  by  man,  and  as  the  instinctive  power  of 
producing  musical  notes  and  rhythms  is  developed  low 
down  in  the  animal  series,  it  would  be  altogether  opposed 
to  the  principle  of  evolution,  if  we  were  to  admit  that 
man's  musical  capacity  has  been  developed  from  the  tones 
used  in  impassioned  speech.  We  must  suppose  that  the 
rhythms  and  cadences  of  oratory  are  derived  from  previously 

*Winwood  Reade,  "The   Martyrdom  of  Man,"  1872,  p.   441,  and 
"  African  Sketch-book,"  1873,  vol.  ii,  p.  313. 
f  Rengger,  "  Saugethiere  von  Paraguay?"  s.  49. 


SECONDARY  SEXUAL  CHARACTERS.  (J53 

developed  musical  powers.*  We  can  thus  understand  how 
it  is  tliat  music,  dancing,  song,  and  poetry  are  such  very 
ancient  arts.  We  may  go  even  furtlier  than  this,  and,  as 
remarked  in  a  former  chapter,  believe  that  musical  sounds 
afforded  one  of  the  bases  for  the  development  of  language,  f 
As  the  males  of  several  quadrumanous  animals  have  their 
vocal  organs  much  more  developed  than  in  the  females,  and 
as  a  gibbon,  one  of  the  anthropomorphous  apes,  pours 
forth  a  whole  octave  of  musical  notes  and  may  be  said  to 
sing,  it  appears  probable  that  the  progenitors  of  man, 
either  the  males  or  females  or  both  sexes,  before  acquiring 
the  power  of  expressing  their  mutual  love  in  articulate 
language,  endeavored  to  charm  each  other  with  musical 
notes  and  rhythm.  So  little  is  known  about  the  use  of  the 
voice  by  the  Quadrumana  during  the  season  of  love,  that 
we  have  no  means  of  judging  whether  the  habit  of  singing 
was  first  acquired  by  our  male  or  female  ancestors.  W^omen 
are  generally  thought  to  possess  sweeter  voices  than  men, 
and  as  far  as  this  serves  as  any  guide,  we  may  infer  that 
they  first  acquired  musical  powers  in  order  to  attract  the 
other  sex.  I  But,  if  so,  this  must  have  occured  long  ago, 
before  our  ancestors  had  become  sufficiently  human  to  treat 
and  value  their  women  merely  as  useful  slaves.    The  impas- 

*See  the  very  interesting  discussion  on  the  "  Origin  and  Function 
of  Music,"  by  Mr.  Herbert  Spencer,  in  his  collected  "Essays,"  1858, 
p.  359.  Mr.  Spencer  comes  to  an  exactly  opposite  conclusion  to  that 
at  which  I  have  arrived.  He  concludes,  as  did  Diderot  formerly, 
that  the  cadences  used  in  emotional  speech  afford  the  foundation 
from  which  music  has  been  developed;  while  I  conclude  that  musical 
notes  and  rhythms  were  first  acquired  by  the  male  or  female  progen- 
itors of  mankind  for  the  sake  of  charming  the  opposite  sex.  Thus 
musical  tones  became  firmly  associated  with  some  of  the  strongest 
l)assions  an  animal  is  capable  of  feeling,  and  are  consequently  used 
instinctively,  or  through  association  when  strong  emotions  are 
expressed  in  speech.  Mr.  Spencer  does  not  offer  any  satisfactory 
explanation,  nor  can  I,  why  high  or  deep  notes  should  be  expressive, 
both  with  man  and  the  lower  animals,  of  certain  emotions.  Mr. 
Spencer  gives  also  an  interesting  discussion  on  the  relations  between 
poetry,  recitative  and  song. 

f  I  find  in  Lord  Monboddo's  "Origin  of  Language,"  vol.  i,  (1774), 
p.  469,  that  Dr.  Blacklock  likewise  thought  "that  the  first  language 
among  men  was  music,  and  that  before  our  ideas  were  expressed  by 
articulate  sounds  they  were  communicated  by  tones  varied  according 
to  different  degrees  of  gravity  and  acuteness." 

^See  an  interesting  discussion  on  this  subject,  by  Hackel,  "  Gener- 
elle  Morph,"  B.  ii,  1866,  s.  246. 


654  THE  DESCENT  OF  MAN. 

sioned  orator,  bard,  or  musician,  when  with  his  varied 
tones  and  cadences  he  excites  the  strongest  emotions  in  his 
hearers,  little  suspects  that  he  uses  the  same  means  by 
which  his  half-human  ancestors  long  ago  aroused  each 
other's  ardent  passions,  during  their  courtship  and  rivalry. 

The  Lifiuence  of  Beauty  in  Determining  the  Marriages 
of  Mankind. — In  civilized  life  man  is  largely,  but  by  no 
means  exclusively,  influenced  in  the  choice  of  his  wife  by 
external  appearance;  but  we  are  chiefly  concerned  with 
primeval  times,  and  our  only  means  of  forming  a  judgment 
on  this  subject  is  to  study  the  habits  of  existing  semi- 
civilized  and  savage  nations.  If  it  can  be  shown  that  the 
men  of  different  races  prefer  women  having  various  char- 
acteristics, or  conversely  with  the  women,  we  have  then  to 
inquire  whether  such  choice,  continued  during  many  gene- 
rations, would  produce  any  sensible  effect  on  the  race, 
either  on  one  sex  or  both,  according  to  the  form  of  inherit- 
ance which  has  prevailed. 

It  will  be  well  flrst  to  show  in  some  detail  that  savages 
pay  the  greatest  attention  to  their  personal  appearance.* 
That  they  have  a  passion  for  ornament  is  notorious;  and  an 
English  philosopher  goes  so  far  as  to  maintain  that  clothes 
were  first  made  for  ornament  and  not  for  warmth.  As 
Prof.  Waitz  remarks:  "  however  poor  and  miserable  man 
is  he  finds  a  pleasure  in  adorning  himself."  The  extrava- 
gance of  the  naked  Indians  of  South  America  in  decorat- 
ing themselves  is  shown  '*  by  a  man  of  large  stature  gain- 
ing with  difficulty  enough  by  the  labor  of  a  fortnight  to 
procure  in  exchange  the  chtca  necessary  to  paint  himself 
red."'  f     The  ancient  barbarians  of   Europe,   during   the 

*  A  full  and  excellent  account  of  tlie  manner  in  wbicli  savages  in 
all  parts  of  tlie  world  ornament  themselves,  is  given  by  the  Italian 
traveler,  Prof.  Mantegazza,  "Rio  de  la  Plata,  Viaggi  e  Studi," 
1867,  pp.  525-545  ;  all  the  following  statements,  when  other  refer- 
ences are  not  given,  are  taken  from  this  work.  See,  also,  Waitz, 
"Introduction  to  Anthropolog.,"  Eng.  translat.,  vol.  i,  1863,  p.  275, 
et  passim.  Lawrence  also  gives  very  full  details  in  his  "Lectures 
on  Physiology,"  1822.  Since  this  chapter  was  written  Sir  J.  Lub- 
bock has  published  his  "Origin  of  Civilization,"  1870,  in  which 
there  is  an  interesting  chapter  on  the  present  subject,  and  from 
which  (pp.  42,  48)  I  have  taken  some  facts  about  savages  dyeing 
their  teeth  and  hair  and  piercing  their  teeth. 

f  Humboldt,  "Personal  Narrative,"  Eng.  translat.,  vol.  iv,  p.  515; 
on  the  imagination  shown  in  painting  the  body,  p.  522;  on  modifying 
the  form  of  the  calf  of  the  leg.  p.  406. 


SECONDARY  SEXUAL  CHARACTERS.  655 

Reindeer  period,  brought  to  their  caves  any  brilliant  or 
singular  objects  which  they  happened  to  find.  Savages  at 
the  present  day  everywhere  deck  themselves  with  plumes, 
necklaces,  armlets,  ear-rings,  etc.  They  paint  themselves 
in  the  most  diversified  manner.  ''  If  painted  nations,"  as 
Humboldt  observes,  ^^had  been  examined  with  the  same 
attention  as  clothed  nations,  it  would  have  been  perceived 
that  the  most  fertile  imagination  and  the  most  mutable 
caprice  have  created  the  fashions  of  painting,  as  well  as 
those  of  garments/' 

In  one  part  of  Africa  the  eyelids  are  colored  black;  in 
another  the  nails  are  colored  yellow  or  purple.  In  many 
places  the  hair  is  dyed  of  various  tints.  In  different  coun- 
tries the  teeth  are  stained  black,  red,  blue,  etc.,  and  in 
the  Malay  Archipelago  it  is  thought  shameful  to  have  white 
teeth,  "  like  those  of  a  dog.''  Not  one  great  country  can 
be  named,  from  the  Polar  regions  in  the  north  to  New 
Zealand  in  the  south,  in  which  the  aborigines  do  not  tattoo 
themselves.  This  practice  was  followed  by  the  Jews  of  old, 
and  by  the  ancient  Britons.  In  Africa  some  of  the  natives 
tattoo  themselves,  but  it  is  a  much  more  common  practice 
to  raise  protuberances  by  rubbing  salt  into  incisions  made 
in  various  parts  of  the  body;  and  these  are  considered  by 
the  inhabitants  of  Kordofan  and  Darfur  ^^to  be  great  per- 
sonal attractions."  In  the  Arab  countries  no  beauty  can 
be  perfect  until  the  cheeks  ''  or  temples  have  been  gashed."* 
In  South  America,  as  Humboldt  remarks,  "2k  mother  would 
be  accused  of  culpable  indifference  toward  her  children  if 
she  did  not  employ  artificial  means  to  shape  the  calf  of  the 
leg  after  the  fashion  of  the  country."  In  the  Old  and  Xew 
Worlds  the  shape  of  the  skull  was  formerly  modified  during 
infancy  in  the  most  extraordinary  manner,  as  is  still  the 
case  in  many  places,  and  such  deformities  are  considered 
ornamental.  For  instance,  the  savages  of  Colombiaf 
deem  a  much  flattened  head  "  an  essential  point  of  beauty." 

The  hair  is  treated  with  especial  care  in  various  countries; 
it  is  allowed  to  grow  to  full  length,  so  as  to  reach  to  the 
ground,  or  is  combed  into  '^a  compact  frizzled  mop,  which 

*"  The  Nile  Tributaries,"  1867;  "  The  Albert  N'yanza,"  1866,  vol. 
i.  p.  218. 

f  Quoted  by  Pricbard.  "  Phys.  Hist,  of  Mankind,"  4tU  edit.,  vol.  i, 
1851,  p.  331, 


656  THE  DESCENT  OF  MAN. 

is  the  Papuan's  pride  and  glory."*  In  Northern  Africji  '*  a 
man  requires  a  period  of  from  eight  to  ten  years  to  perfect 
his  coilfure/'  With  other  nations  the  head  is  shaved,  and  in 
parts  of  South  America  and  Africa  even  the  eyebrows  and 
eyelashes  are  eradicated.  The  natives  of  the  Upper  Nile 
knock  out  the  four  front  teeth,  saying  that  tliey  do  not 
wish  to  resemble  brutes.  Farther  south  the  Batokas  knock 
out  only  the  two  upper  incisors,  which,  as  Livingstonef 
remarks,  gives  the  face  a  hideous  appearance,  owing  to  the 
prominence  of  the  lower  jaw;  but  these  people  think  the 
presence  of  the  incisors  most  unsightly,  and  on  beholding 
some  Europeans,  cried  out:  *^  Look  at  the  great  teeth  V 
The  chief  Sebituani  tried  in  vain  to  alter  this  fashion.  In 
various  parts  of  Africa  and  in  the  Malay  Archipelago  the 
natives  file  the  incisors  into  points  like  those  of  a  saw,  or 
pierce  them  with  holes,  into  which  they  insert  studs. 

As  the  face  with  us  is  chiefly  admired  for  its  beauty,  so 
with  savages  it  is  the  chief  seat  of  mutilation.  In  all 
quarters  of  the  world  the  septum,  and  more  rarely  the 
wings  of  the  nose  are  pierced;  rings,  sticks,  feathers  and 
other  ornaments  being  inserted  into  the  holes.  The  ears  are 
everywhere  pierced  and  similarly  ornamented,  and  with  the 
Botocudos  and  Lenguas  of  South  America  the  hole  is 
gradually  so  much  enlarged  that  the  lower  edge  touches 
the  shoulder.  In  North  and  South  America  and  in  Africa 
either  the  upper  or  lower  lip  is  pierced;  and  with  the  Boto- 
cudos the  hole  in  the  lower  lip  is  so  large  that  a  disk  of  wood, 
four  inches  in  diameter,  is  placed  in  it.  Mantegazza  gives 
a  curious  account  of  the  shame  felt  by  a  South  American 
native,  and  of  the  ridicule  which  he  excited,  when  he  sold  his 
tembeta — the  large  colored  piece  of  wood  which  is  passed 
through  the  hole.  In  Central  Africa  the  Avomen  perforate 
the  lower  lip  and  wear  a  crystal,  which,  from  tlie  movement 
of  the  tongue,  has  ''^  a  wriggling  motion,  indescribably  ludi- 
crous during  conversation. ''  The  wife  of  the  chief  of  Latooka 
told  Sir  S.  Baker, ;[  that  Lady  Baker  ^'  would  be  much  im- 
proved if  slie  would  extract  her  four  front  teeth  from  the 
lower  jaw  and  wear  the  long-pointed  polished  crystal  in  her 

*0n  the  Papuans,  Wallace,  "The  Malay  Archipelago,"  vol.  li,  p. 
445.  On  the  coiffure  of  the  Africans,  Sir  S.  Baker,  "The  Albert 
N'yanza,"  vol.  i,  p.  210. 

+  "Travels," p.  533. 

\  '•  The  Albert  N'j^anza,"  1866,  vol.  i,  p.  317. 


SECONDARY  SEXUAL  CHARACTERS,  657 

under  lip."  Farther  south  with  the  Makalolo,  the  upper 
lip  is  perforated,  and  a  large  metal  and  bamboo  ring,  called 
apelele,  is  worn  in  the  hole.  "  This  caused  the  lip  in  one  case 
to  project  two  inches  beyond  the  tip  of  the  nose;  and  when 
tlie  laidy  smiled  the  contraction  of  the  muscles  elevated 
it  oyer  the  eyes.  ^  Why  do  the  women  wear  these  things?' 
the  venerable  chief,  Chinsurdi,  was  asked.  Evidently  sur- 
prised at  such  a  stupid  question,  lie  replied:  '  For  beauty  ! 
They  are  the  only  beautiful  things  women  have;  men  have 
beards,  women  have  none.  What  kind  of  a  person  would 
she  be  without  the  pelele?  She  would  not  be  a  woman  at 
all  with  a  mouth  like  a  man,  but  no  beard.'  "* 

Hardly  any  part  of  the  body,  which  can  be  unnaturally 
modified,  has  escaped.  The  amount  of  suffering  thus 
caused  must  have  been  extreme,  for  many  of  the  operations 
require  several  years  for  their  completion,  so  that  the  idea 
of  their  necessity  must  be  imperative.  The  motives  are 
various;  the  men  paint  their  bodies  to  make  themselves 
appear  terrible  in  battle;  certfiin  mutilations  are  connected 
with  religious  rites,  or  they  mark  the  age  of  puberty,  or  the 
rank  of  the  man,  or  they  serve  to  distinguish  the  tribes. 
Among  savages  the  same  fashions  prevail  for  long  periods,! 
and  thus  mutilations,  from  whatever  cause  first  made,  soon 
come  to  be  valued  as  distinctive  marks.  But  self-adorn- 
ment, vanity  and  the  admiration  of  others  seem  to  be  the 
commonest  motives.  In  regard  to  tattooing,  I  was  told  by 
the  missionaries  in  New  Zealand  that  when  they  tried  to 
persuade  some  girls  to  give  up  the  practice  they  answered: 
"  W^e  must  just  have  a  few  lines  on  our  lips;  else  when  we 
grow  old  we  shall  be  so  very  ugly."  With  the  men  of  New 
Zealand,  a  most  capable  judge  J  says:  "To  have  fine 
tattoed  faces  was  the  great  ambition  of  the  young,  both  to 
render  themselves  attractive  to  the  ladies  and  conspicuous 
in  war."    A  star  tattooed  on  the  forehead  and  a  spot  on 

*  Livingstone,  "British  Association,"  1860;  report  given  in  the 
"Athenaeum,"  July  7,  1860,  p.  29. 

f  Sir  S.  Baker  (ibid.,  vol.  i,  p.  210)  speaking  of  the  natives  of 
Central  Africa,  says:  "  Every  tribe  has  a  distinct  and  unchanging 
fashion  for  dressing  the  hair."  See  Agassiz  ("Journey  in  Brazil," 
1868,  p.  318)  on  the  invariability  of  the  tattooing  of  the  Amazonian 
Indians. 

^Rev.  K.  Taylor,  "New  Zealand  and  Its  Inhabitants,"  1855,  p. 
153. 


658  THE  DESCENT  OF  MAN, 

the  chill  are  thought  by  the  women  in  one  part  of  Africa 
to  be  irresistible  attractions.*  In  most,  but  not  all  parts  of 
tlie  world,  the  men  are  more  ornamented  than  tlie  women, 
and  often  in  a  different  manner;  sometimes,  though  rarely, 
the  women  are  hardly  at  all  ornamented.  As  the  women 
are  made  by  savages  td  perform  the  greatest  share  of  the 
work,  and  as  they  are  not  allowed  to  eat  the  best  kinds  of 
food,  so  it  accords  with  the  characteristic  selfishness  of  man 
that  they  should  not  be  allowed  to  obtain  or  use  the  finest 
ornaments.  Lastly,  it  is  a  remarkable  fact,  as  proved  by 
the  foregoing  quotations,  that  the  same  fashions  in  modi- 
fying the  shape  of  the  head,  in  ornamenting  the  hair,  in 
painting,  tattooing,  in  perforating  the  nose,  lips  or  ears,  in 
removing  or  filing  the  teeth,  etc.,  now  prevail,  and  have 
,long  prevailed,  in  the  most  distant  quarters  of  the  world. 
It  is  extremely  improbable  that  these  practices,  followed  by 
so  many  distinct  nations,  should  be  due  to  tradition  from 
any  common  source.  They  indicate  the  close  similarity  of 
the  mind  of  man,  to  whatever  race  he  may  belong,  just  as 
do  the  almost  universal  habits  of  dancing,  masquerading 
and  making  rude  pictures. 

Having  made  these  preliminary  remarks  on  the  admira- 
tion felt  by  savages  for  various  ornaments  and  for  de- 
formities most  unsightly  in  our  eyes,  let  us  see  how  far  the 
men  are  attracted  by  the  appearance  of  their  women  and 
what  are  their  ideas  of  beauty.  I  have  heard  it  maintained 
that  savages  are  quite  indifferent  about  the  beauty  of  their 
women,  valuing  them  solely  as  slaves;  it  may,  therefore,  be 
well  to  observe  that  this  conclusion  does  not  at  all  agree 
with  the  care  which  the  women  take  in  ornamenting  them- 
selves, or  with  their  vanity.  Burchell  \  gives  an  amusing 
account  of  a  Bush-woman  who  used  as  much  grease,  red 
ocher  and  shining  powder  ''  as  would  have  ruined  any  but 
a  very  rich  husband."  She  displayed  also  ^^  much  vanity 
and  too  evident  a  consciousness  of  her  superiority."  Mr. 
Winwood  Reade  informs  me  that  the  negroes  of  the  West 
Coast  often  discuss  the  beauty  of  their  women.  Some 
competent  observers  have  attributed  the  fearfully  common 
practice   of   infanticide   partly  to   the   desire   felt  by  the 

*Mantegazza,  "  Viaggi  e  Studi,"  p.  542, 
f  "  Travels  in  S.  Africa,"  1834,  vol.  i,  p.  414. 


SECOND  A  R  T  SEX  UAL  CHAR  A  CTBR8.  659 

women  to  retain  their  good  looks.*  In  several  regions  the 
women  wear  charms  and  use  love-philters  to  gain  the  affec- 
tions of  the  men;  and  Mr.  Brown  enumerates  four  plants 
used  for  this  purpose  by  the  women  of  Northwestern 
America.  \ 

Hearne,^  an  excellent  observer,  who  lived  many  years 
with  the  American  Indians,  says,  in  speaking  of  the  women: 
^^  Ask  a  Northern  Indian  what  is  beauty,  and  he  will 
answer,  a  broad  flat  face,  small  eyes,  high  cheek-bones, 
three  or  four  broad  black  lines  across  each  cheek,  a  low 
forehead,  a  large  broad  chin,  a  clumsy  hook  nose,  a  tawny 
hide  and  breasts  hanging  down  to  the  belt."  Pallas,  who 
visited  the  northern  parts  of  the  Chinese  empire,  says: 
"  Those  women  are  preferred  who  have  the  Mandschu 
form;  that  is  to  say,  a  broad  face,  high  cheek-bones,  very 
broad  noses,  and  enormous  ears;'^§  and  Vogt  remarks  that 
the  obliquity  of  the  eye,  which  is  proper  to  the  Chinese 
and  Japanese,  is  exaggerated  in  their  pictures  for  the  pur- 
pose, as  it  *^  seems,  of  exhibiting  its  beauty,  as  contrasted 
with  the  eye  of  the  red-haired  barbarians."  It  is  well 
known,  as  Hue  repeatedly  remarks,  that  the  Chinese  of  the 
interior  thi^k  Europeans  hideous,  with  their  white 
skins  and  prckninent  noses.  The  nose  is  far  from  being 
too  prominent,  according  to  our  ideas,  in  the  natives  of 
Ceylon;  yet  ^'the  Chinese  in  the  seventh  century,  accus- 
tomed to  the  flat  features  of  the  Mongol  races,  were  sur- 
prised at  the  prominent  noses  of  the  Cingalese;  and  Thsang 
describes  them  as  having  *  the  beak  of  a  bird,  with  the 
body  of  a  man.^" 

Finlayson,  after  minutely  describing  the  people  of 
Cochin  China,  says  that  their  rounded  heads  and  faces  are 
their  chief  characteristics;  and,  he  adds,  ''the  roundness 
of  the  whole  countenance  is  more  striking  in  the  women, 

*  See  for  references,  Gerland  ' '  Ueber  das  Aussterben  der  Natur- 
volker,"  1868,  ss.  51,  53,  55;  also  Azara,  "Voyages,"  etc.,  torn,  ii,  p. 
116. 

f  On  the  vegetable  productions  used  by  the  Northwestern  Ameri- 
can Indians,  "  Pharmaceutical  Journal,"  vol.  x. 

J  "  A  Journey  from  Prince  of  Wales  Fort,"  8vo.  edit.,  1796,  p.  89. 

§  Quoted  by  Prichard,  "  Phys.  Hist,  of  Mankind,"  3d  edit.,  vol.  iv, 
1844,  p.  519;* Vogt,  "Lectures  on  Man,"  Eng.  translat.  p.  129.  On 
the  opinion  of  the  Chinese  on  the  Cingalese,  E.  Tennent,  "  Ceylon," 
1859,  vol.  ii,  p.  107. 


660  THE  DESCENT  OF  MAN. 

who  are  reckoned  beautiful  in  proportion  as  thej  display 
this  form  of  face."  The  Siamese  have  snudl  noses  with 
divergent  nostrils,  a  wide  mouth,  rather  tliick  lips,  a 
remarkably  large  face,  with  very  high  and  broad  cheek- 
bones. It  is,  therefore,  not  wonderful  that  **  beauty, 
according  to  our  notion,  is  a  stranger  to  them.  Yet  they 
consider  their  own  females  to  be  much  more  beautiful  than 
those  of  Europe."* 

It  is  well  known  that  witli  many  Hottentot  women  the 
posterior  part  of  the  body  projects  in  a  wonderful  manner; 
they  are  steatopygous;  and  iSir  Andrew  Smith  is  certain 
that  this  peculiarity  is  greatly  admired  by  the  men.f  He 
once  saw  a  woman  who  was  considered  a  beauty,  and  she 
was  so  immensely  developed  behind  that  when  seated  on 
level  ground  she  could  not  rise,  and  had  to  push  herself 
along  until  she  came  to  a  slope.  Some  of  the  women  in 
various  negro  tribes  have  the  same  peculiarity;  and,  accord- 
ing to  Burton,  the  Somal  men  *^are  said  to  choose  their 
wives  by  ranging  them  in  a  line  and  by  picking  her  out 
who  projects  farthest  a  tergo.  Nothing  can  be  more  hate- 
ful to  a  negro  than  the  opposite  form. "J 

AVitli  respect  to  color,  the  negroes  railed  Mungo  Park 
on  the  whiteness  of  his  skin  and  the  prominence  of  his 
nose,  both  of  which  they  considered  as  ^^  unsightly  and 
unnatural  conformations."  He  in  return  praised  the  glossy 
jet  of  their  skins  and  the  lovely  depression  of  their  noses; 
this  they  said  was  ''honeymouth,"  nevertheless  they  gave 
him  food.  The  African  Moors,  also,  ^'  knitted  their  brows 
and  seemed  to  shudder"  at  the  whiteness  of  his  skin.  On 
the  eastern  coast  the  negro  boys  when  they  saw  Burton, 
cried  out:  ^*  Look  at  the  white  man;  does  he  not  look  like 
a  white  ape?"  On  the  western  coast,  as  Mr.  Winwood 
Reade  informs  me,  the  negroes  admire  a  very  black  skin 
more   than   one   of   a  lighter   tint.     But  their  horror  of 

*  Pri chard,  as  taken  from  Crawfurd  and  Finlayson,  "  Pbys.  Hist, 
of  Mankind,"  vol.  iv,  pp.  534,  535. 

f  Idem  illustrissimus  viator  dixit  mibi  praecinctorium  vel  tabulam 
foeminsB,  quod  nobis  teterrimum  est,  quondam  perniagno  fcstimari  ab 
bominibus  in  bac  gente.  Nunc  res  mutata  est,  et  censent  talem  con- 
formationem  minime  optandam  esse. 

f'Tbe  Antbropological  Review,"  Nov.,  1864,  p.  237.  For  addi- 
tional reference,  see  VVaitz,  "  Introduct.  to  Anthropology,"  Eng. 
translat.,  1863,  vol.  i,  p.  105. 


8EC0NDARt  SEXUAL  CHARACTERS.  6G1 

whiteness  may  be  attributed,  according  to  this  same 
traveler,  partly  to  the  belief  held  by  most  negroes  that 
demons  and  spirits  are  white,  and  partly  to  their  thinking 
it  a  sign  of  ill- health. 

The  Banyai  of  the  more  southern  part  of  the  continent 
are  negroes,  but  *'a  great  many  of  them  are  of  a  light 
coffee-and-milk  color,  and,  indeed,  this  color  is  considered 
handsome  throughout  the  whole  country;"  so  that  here  we 
have  a  different  standard  of  taste,  ^^ith  the  Kafirs,  who 
differ  much  from  negroes,  ''  the  skin,  except  among  the 
tribes  near  Delagoa  Bay,  is  not  usually  black,  the  prevail- 
ing color  being  a  mixture  of  black  and  red,  the  most 
common  shade  being  chocolate.  Dark  complexions  as 
being  most  common  are  naturally  held  in  the  highest 
esteem.  To  be  told  that  he  is  light  colored  or  like  a  white 
man  would  be  deemed  a  very  poor  compliment  by  a  Kafir. 
I  have  heard  of  one  unfortunate  man  who  was  so  very  fair 
that  no  girl  would  marry  him."  One  of  the  titles  of  the 
Zulu  king  is:  "You  who  are  black."*  Mr.  Galton,  in 
speaking  to  me  about  the  natives  of  S.  Africa,  remarked 
that  their  ideas  of  beauty  seem  very  different  from  ours; 
for  in  one  tribe  two  slim,  slight  and  pretty  girls  were  not 
admired  by  the  natives. 

Turning  to  other  quarters  of  the  world:  in  Java  a  yellow, 
not  a  white  girl,  is  considered,  according  to  Madame 
Pfeiffer,  a  beauty.  A  man  of  Cochin  China  "  spoke  with 
contempt  of  the  wife  of  the  English  ambassador,  that  she 
had  white  teeth  like  a  dog  and  a  rosy  color  like  that  of 
potato  flowers."  We  have  seen  that  the  Chinese  dislike 
our  white  skin  and  that  the  North  Americans  admire  "a 
tawny  hide."  In  South  America  the  Yuracaras,  who 
inhabit  the  wooded,  damp  slopes  of  the  eastern  Cordillera, 
are  remarkably  pale  colored,  as  their  name  in  their  own 
language  expresses;  nevertheless,  they  consider  European 
women  as  very  inferior  to  their  own.  \ 

*Mungo  Park's  "  Travels  in  Africa,"  4to.,  1816,  pp.  53,  131.  Bur- 
ton's statement  is  quoted  by  Scliaaffbausen,  "  Archiv.  fur  Antbro- 
polog.."  1866,  s.  163.  On  tbe  Banyai,  Livingstone,  "Travels,"  p. 
64.  On  tbe  Kafirs,  tbe  Rev.  J.  Scbooter,  "Tbe  Kafirs  of  Natal  and 
tbe  Zulu  Country,"  1857,  p.  1. 

f  For  tbe  Javans  and  Cocbin-Cliinese,  see  Waitz,  "  Tntroduct.  to 
Antbropology,"  Eng.  translat.,  vol.  i,  p.  305.  On  tbe  Yuracaras,  A. 
d'Orbigny,  as  quoted  in  Pricbard,  '*  Pbys.  Hist,  of  Mankind,"  vol.  v, 
3d  edit.,  p.  476. 


662  THE  DESCENT  OF  MAN. 

In  several  of  the  tribes  of  North  America  the  hair  on  the 
head  grows  to  a  wonderful  length;  and  Catlin  gives  a 
curious  proof  how  much  this  is  esteemed,  for  the  chief  of 
the  Crows  was  elected  to  this  office  from  having  the  longest 
hair  of  any  man  in  the  tribe;  namely,  ten  feet  and  seven 
inches.  The  Aymaras  and  Quichuas  of  South  America 
likewise  have  very  long  hair;  and  this,  as  Mr.  D.  Forbes 
informs  me,  is  so  much  valued  as  a  beauty,  that  cutting  it 
off  was  the  severest  punishment  which  he  could  inflict  on 
them.  In  both  the  northern  and  southern  halves  of  the 
continent  the  natives  sometimes  increase  the  apparent 
length  of  their  hair  by  weaving  into  it  fibrous  substances. 
Although  the  hair  on  the  head  is  thus  cherished,  that  on 
the  face  is  considered  by  the  Korth  American  Indians  "  as 
very  vulgar,^'  and  every  hair  is  carefully  eradicated.  This 
practice  prevails  throughout  the  American  continent  from 
Vancouver's  Island  in  the  north  to  Terra  del  Fuego  in  the 
south.  When  York  Minster,  a  Fuegian  on  board  the 
*'  Beagle,^'  was  taken  back  to  his  country,  the  natives  told 
him  he  ought  to  pull  out  the  few  short  hairs  on  his  face. 
They  also  threatened  a  young  missionary,  who  was  left  for 
a  time  with  them,  to  strip  him  naked  and  pluck  the  hairs 
from  his  face  and  body,  yet  he  was  far  from  being  a  hairy 
man.  This  fashion  is  carried  so  far  that  the  Indians  of 
Paraguay  eradicate  their  eyebrows  and  eyelashes,  saying 
that  they  do  not  wish  to  be  like  horses.* 

It  is  remarkable  that  throughout  the  world  the  races 
which  are  almost  completely  destitute  of  a  beard  dislike 
hairs  on  the  face  and  body,  and  take  pains  to  eradicate 
them.  The  Kalmucks  are  beardless  and  they  are  well 
known,  like  the  Americans,  to  pluck  out  all  straggling 
hairs  ;  and  so  it  is  with  the  Polynesians,  some  of  the 
Malays  and  the  Siamese.  Mr.  Veitch  states  that  the 
Japanese  ladies  "  all  objected  to  our  whiskers,  considering 
them  very  ugly,  and  told  us  to  cut  them  off  and  be  like 
Japanese  men."  The  New  Zealand ers  have  short,  curled 
beards;  yet  they  formerly  plucked  out  the  hairs  on  the 
face.  They  had  a  saying  that  "  there  is  no  woman  for  a 
hairy  man;''   but  it  would   appear   that   the   fashion   has 

*  "  North  American  Indians,"  by  G.  Catlin,  Bdedit.  1842,  vol.  i,  p. 
49;  vol.  ii.  p.  227.  On  the  natives  of  Vancouver's  Island,  see  Sproat, 
"  Scenes  and  Studies  of  Savage  Life,"  1868,  p.  25.  On  the  Indians 
of  Paraguay,  Azara,  "  Voyages,"  torn,  ii,  p.  105. 


8BC0NDAR  Y  SKXUA L  CHA RA CTERS.  6H3 

changed  in  New  Zealand,  perhaps  owing  to  the  presence  of 
Europeans,  and  I  am  assured  that  beards  are  now  admired 
by  the  Maories/'* 

On  the  other  hand,  bearded  races  admire  and  greatly 
value  their  beards;  among  the  Anglo-Saxons  every  part  of 
the  body  had  a  recognized  value;  *^the  loss  of  the  beard 
being  estimated  at  twenty  shillings,  while  the  breaking  of 
a  thigh  was  fixed  at  only  twelve."!  ^^  ^^^  ^^st  men  swear 
solemnly  by  their  beards.  We  have  seen  that  Chinsurdi, 
the  chief  of  the  Makalolo  in  Africa,  thought  that  beards 
were  a  great  ornament.  In  the  Pacific  the  Fijian^s  beard 
is  "  profuse  and  bushy,  and  is  his  gi*eatest  pride;"  while 
the  inhabitants  of  the  adjacent  archipelagoes  of  Tonga  and 
Samoa  are  beardless  and  abhor  a  rough  chin."  In  one 
island  alone  of  tlie  Ellice  group  *^the  men  are  heavily 
bearded,  and  not  a  little  proud  thereof."  I 

We  thus  see  how  widely  the  different  races  of  man  differ 
in  their  taste  for  the  beautiful.  In  every  nation  sufficiently 
advanced  to  have  made  effigies  of  their  gods  or  of  their 
deified  rulers,  the  sculptors  no  doubt  have  endeavored  to  ex- 
press their  highest  ideal  of  beauty  and  grandeur.  §  Under 
this  point  of  view  it  is  well  to  compare  in  our  mind  the 
Jupiter  or  Apollo  of  the  Greeks  with  the  Egyptian  or 
Assyrian  statues;  and  these  with  the  hideous  bas-reliefs 
on  the  ruined  buildings  of  Central  America. 

I  have  met  with  very  few  statements  opposed  to  this 
conclusion.  Mr.  Win  wood  Reade,  however,  who  has  had 
ample  opportunities  for  observation,  not  only  with  the 
negroes  of  the  west  coast  of  Africa,  but  with  those  of  the 
interior  who  have  never  associated  with  Europeans,  is  con- 
vinced that  their  ideas  of  beauty  are,  on  the  whole,  the  same 
as  ours;  and  Dr.  Rohlfs  writes  to  me  to  the  same  effect 

*0n  the  Siamese,  Prichard,  ibid,  vol.  iv,  p.  533.  On  the  Japanese, 
Veitch  in  "  Gardeners'  Chronicle,"  1860,  p.  1104.  On  the  New  Zeal- 
anders,  Mantegazza,  "Viaggi  e  Studi,"  1867,  p.  526.  For  the  other 
nations  mentioned,  eee  references  in  Lawrence,  "  Lectures  on  Physi- 
ology," etc.,  1822,  p.  272. 

f  Lubbock,  "Origin  of  avilization,"  1870,  p.  321. 

X  Dr.  Barnard  Davis  quotes  Mr.  Prichard  and  others  for  these  facts 
in  regard  to  the  Polynesians,  in  "  Anthropological  Review,"  April, 
1870,  pp.  185,  191. 

§  Ch.  Comte  has  remarks  to  this  effect  in  bis  "  Traite  de  Legisla- 
tion," 3d  edit.,  1837,  p.  136. 


fi 


064  "THE  DESCENT  OF  MAN. 

with  respect  to  Borneo  and  the  countries  inhabited  by  the 
Pullo  tribes.  Mr.  Reade  found  that  he  agreed  with  the 
negroes  in  their  estimation  of  the  beauty  of  the  native  girls; 
and  that  their  appreciation  of  the  beauty  of  European 
women  corresponded  with  ours.  They  admire  long  hair, 
and  use  artificial  means  to  make  it  appear  abundant;  they 
admire  also  a  beard,  though  themselves  very  scantily  pro- 
vided. Mr.  Reade  feels  doubtful  what  kind  of  nose  is  most 
appreciated;  a  girl  has  been  heard  to  say:  ^^I  do  not  want 
to  marry  him,  he  has  got  no  nose;"  and  this  shows  that  a 
very  flat  nose  is  not  admired.  We  should,  however,  bear 
in  mind  that  the  depressed,  broad  noses  and  projecting 
jaws  of  the  negroes  of  the  west  coast  are  exceptional  types 
with  the  inhabitants  of  Africa.  Notwithstanding  the  fore- 
oing  statements,  Mr.  Reade  admits  that  negroes  "  do  not 
ike  the  color  of  our  skin;  they  look  on  blue  eyes  with  aver- 
sion, and  they  think  our  noses  too  long  and  our  lips  too 
thin."  He  does  not  think  it  probable  that  negroes  would 
ever  prefer  the  most  beautiful  European  woman,  on  the 
mere  grounds  of  physical  admiration,  to  a  good-looking 
negress.  * 

The  general  truth  of  the  principle,  long  ago  insisted  on 
by  Humboldt,!  that  man  admires  and  often  tries  to  exag- 
gerate whatever  characters  nature  may  have  given  him,  is 
shown  in  many  ways.  The  practice  of  beardless  races 
extirpating  every  trace  of  a  beard,  and  often  all  the  hairs 
on  the  body,  affords  one  illustration.  The  skull  has  been 
greatly  modified  during  ancient  and  modern  times  by  many 
nations;  and  there  can  be  little  doubt  that  this  has  been 
practiced,  especially  in  North  and  South  America,  in  order 

*The  "African  Sketch-book,"  vol.  ii,  1873,  pp.  253,  394,  521. 
The  Fuegians,  as  I  have  been  informed  by  a  missionary  who  long 
resided  with  them,  consider  European  women  as  extremely  beautiful; 
but  from  what  we  have  seen  of  the  judgment  of  the  other  al)origines  of 
America,  I  cannot  but  think  that  this  must  be  a  mistake,  unless 
indeed  the  statement  refers  to  the  few  Fuegians  who  have  lived  for 
some  time  with  Europeans,  and  who  must  consider  us  as  superior 
beings.  I  should  add  that  a  most  experienced  observer,  C'apt.  Bur- 
ton, believes  that  a  woman  whom  we  consider  beautiful  is  admired 
throughout  the  world.  "  Anthropological  Review,"  March,  1864,  p. 
245. 

f  "Personal  Narrative,"  Eng.  translat.,  vol.  iv,  p.  518,  and  else- 
where. Mantegazza,  in  his  "  Viaggi  e  Studi,"  strongly  insists  on 
this  same  principle. 


SECONDARY  SEXUAL  CHARACTERS.  665 

to  exaggerate  some  natural  and  admired  peculiarity.  Many 
American  Indians  are  known  to  admire  a  head  so  extremely 
flattened  as  to  appear  to  us  idiotic.  The  natives  on  the 
northwestern  coast  compress  the  head  into  a  pointed  cone; 
and  it  is  their  constant  practice  to  gather  the  hair  into  a 
knot  on  the  top  of  the  head,  for  the  sake,  as  Dr.  Wilson 
remarks,  "of  increasing  the  apparent  elevation  of  the 
favorite  conoid  form."  The  inhabitants  of  Arakhan 
**  admire  a  broad,  smooth  forehead,  and,  in  order  to  pro- 
duce it,  they  fasten  a  plate  of  lead  on  the  lieads  of  the 
new-born  children."  On  the  other  band,  '*a  broad,  well- 
rounded  occiput  is  considered  a  great  beauty"  by  the 
natives  of  the  Fiji  Hands.* 

As  with  the  skull,  so  with  the  nose;  the  ancient  Huns, 
during  the  age  of  Attila,  were  accustomed  to  flatten  the 
noses  of  their  infants  with  bandages,  *'for  the  sake  of 
exaggerating  a  natural  conformation."  \Yith  the  Tahitians, 
to  be  called  long-nose  is  considered  as  an  insult,  and  they 
compress  the  noses  and  foreheads  of  their  children  for  the 
sake  of  beauty.  The  same  holds  with  the  Malays  of 
Sumatra,  the  Hottentots,  certain  negroes  and  the  natives 
of  Brazil,  t  The  Chinese  have  by  nature  unusually  small 
feet;  X  and  it  is  well  known  that  the  women  of  the  upper 
classes  distort  their  feet  to  make  them  still  smaller. 
Lastly,  Humboldt  thinks  that  the  American  Indians  prefer 
coloring  their  bodies  with  red  paint  in  order  to  exaggerate 
their  natural  tint;  and  until  recently  European  women 
added  to  their  naturally  bright  coloi*s  by  rouge  and 
white  cosmetics ;  but  it  may  be  doubted  whether  barbarous 
nations  have  generally  had  any  such  intention  in  paint- 
ing themselves.    ' 

*  On  the  skalls  of  the  American  tribes,  see  Nott  and  Gliddon, 
••  Types  of  Mankind,"  1854.  p.  440;  Prichard,  "  Phys.  Hist,  of  Man- 
kind," vol.  i,  3d  edit.,  p.  321  ;  on  the  natives  of  Arakhan,  ibid,  vol. 
iv,  p.  537.  Wilson,  "Physical  Ethnology,"  Smithsonian  Institution, 
1863,  p.  288;  on  the  Fijians,  p.  290.  Sir  J.  Lubbock  r"  Prehistoric 
Times,"  2d  edit.,  1869,  p.  506)  gives  an  excellent  resume  on  this  sub- 
ject. 

f  On  the  Huns,  Godron,  "  De  I'Espece,"  tom.  ii,  1859,  p.  300.  On 
the  Tahitians,  Waitz,  "  Anthropolog.,"  Eng.  translat.,  vol.  i.  p.  305. 
Marsden,  quoted  by  Prichard,  "  Phys.  Hist,  of  Mankind,"  3d  edit., 
vol.  V,  p.  67.     Lawrence,  "Lectures  on  Physiology,"  p.  337. 

^This  fact  wa.s  ascertained  in  the  "  Reise  der  No  vara  :  Anthropo- 
log. Thiel,"  Dr.  Weisbach,  1867,  s.  265. 


666  i'HE  DESCt^NT  OP  MaI^. 

In  the  fashions  of  our  own  dress  we  see  exactly  the  same 
principle  and  the  same  desire  to  carry  every  point  to  an 
extreme;  we  exhibit,  also,  the  same  spirit  of  emulation. 
But  the  fashions  of  savages  are  far  more  permanent  than 
ours;  and  whenever  tlieir  bodies  are  artiticially  modified, 
this  is  necessarily  the  case.  The  Arab  women  of  the  Upper 
Nile  occupy  about  three  days  in  dressing  their  hair;  tliey 
never  imitate  other  tribes,  **  but  simply  vie  with  each  otlier 
in  the  superlativeness  of  their  own  style. ^*  Dr.  Wilson,  in 
speaking  of  the  compressed  skulls  of  various  American 
races,  adds,  '^sucli  usages  are  among  the  least  eradicable, 
and  long  survive  the  shock  of  revolutions  that  change 
dynasties  and  efface  more  important  national  peculiarities."* 
The  same  principle  comes  into  play  in  the  art  of  breeding; 
and  we  can  thus  understand,  as  I  have  elsewhere  explained,! 
the  wonderful  development  of  the  many  races  of  animals 
and  plants,  which  have  been  kept  merely  for  ornament. 
Fanciers  always  wish  each  character  to  be  somewhat 
increased;  they  do  not  admire  a  medium  standard;  they  cer- 
tainly do  not  desire  any  great  and  abrupt  change  in  the 
character  of  their  breeds;  they  admire  solely  what  they  are 
accustomed  to,  but  they  ardently  desire  to  see  each  char- 
acteristic feature  a  little  more  developed. 

The  senses  of  man  and  of  the  lower  animals  seem  to  be 
so  constituted  that  brilliant  colors  and  certain  forms,  as 
well  as  harmonious  and  rhythmical  sounds,  give  pleasure 
and  are  called  beautiful;  but  why  this  should  be  so  we 
know  not.  It  is  certainly  not  true  that  there  is  in  the 
mind  of  man  any  universal  standard  of  beauty  with  respect 
to  the  human  body.  It  is,  however,  possible  that  certain 
tastes  may  in  the  course  of  time  become  inherited, 
though  there  is  no  evidence  in  favor  of  this  belief;  and,  if 
so,  each  race  would  possess  its  own  innate  ideal  standard  of 
beauty.  It  has  been  argued  I  that  ugliness  consists  in  an 
approach  to  the  structure  of  the  lower  animals,  and  no 
doubt  this  is  partly  true  with  the  more  civilized  nations, 
in  which  intellect  is  highly  appreciated;  but  this  explana- 

* "  Smitlisonian  Institution,"  1863,  p.  289.  On  tlie  fashions  of 
Arab  women,  Sir  S.  Baker,  "  The  Nile  Tributaries,"  1867,  p.  121. 

f  "The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  i,  p.  214;  vol.  ii,  p.  240. 

\  ScbaafEhausen,  "  Arcbiv.  fiir  Antbropologie,"  1866,  s.  16^ 


&WONl)Aiit  SEXUAL  CSaUACTBRS.  66? 

tion  will  hardly  apply  to  all  forms  of  ugliness.  The  men 
of  each  race  prefer  what  they  are  accustomed  to;  they 
cannot  endure  any  great  change;  hut  they  like  variety,  and 
admire  each  characteristic  carried  to  a  moderate  extreme.* 
Men  accustomed  to  a  nearly  oval  face,  to  straight  and 
regular  features  and  to  bright  colors,  admire,  as  we  Euro- 
])cans  know,  these  points  when  strongly  developed.  On 
the  other  hand,  men  accustomed  to  a  broad  face,  with  high 
cheek-bones,  a  depressed  nose  and  a  black  skin  admire 
these  peculiarities  when  strongly  marked.  No  doubt 
characters  of  all  kinds  may  be  too  much  developed  for 
beauty.  Hence  a  perfect  beauty,  which  implies  many 
characters  modified  in  a  particular  manner,  will  be  in  every 
race  a  prodigy.  As  the  great  anatomist  Bichat  long  ago 
said,  if  every  one  were  cast  in  the  same  mold  there  would 
be  no  such  thing  as  beauty.  If  all  our  women  were  to 
become  as  beautiful  as  the  Venus  de  Medici  we  should 
for  a  time  be  charmed,  but  we  should  soon  wish  for  variety; 
and,  as  soon  as  we  had  obtained  variety,  we  should  wish 
to  see  certain  characters  a  little  exaggerated  beyond  the 
then  existing  common  standard. 

*  Mr.  Bain  has  collected  ("  Mental  and  Moral  Science,"  1868,  pp. 
804-314)  about  a  dozen  more  or  less  different  theories  of  the  idea  of 
beauty;  but  none  is  quite  the  same  as  that  here  given. 


668  THE  DESCENT  OF  MAN, 


CHAPTER   XX. 

SECONDARY     SEXUAL     CHARACTERS    OF      MAN — Continued. 

On  the  effects  of  the  continued  selection  of  women  according  to  a 
different  standard  of  beauty  in  each  race — On  the  causes  which 
interfere  with  sexual  selection  in  civilized  and  savage  nations — 
Conditions  favorable  to  sexual  selection  during  primeval  times — 
On  the  manner  of  action  of  sexual  selection  with  mankind — On 
the  women  in  savage  tribes  having  some  power  to  choose  their 
husbands — Absence  of  hair  on  the  body  and  development  of  the 
beard — Color  of  the  skin — Summary. 

We  have  seen  in  the  last  chapter  that  with  all  barbarous 
races  ornaments,  dress  and  external  appearance  are  highly- 
valued;  and  that  the  men  judge  of  the  beauty  of  their 
women  by  widely  different  standards.  We  must  next 
inquire  whether  this  preference  and  the  consequent  selec- 
tion, during  many  generations,  of  those  women  which 
appear  to  the  men  of  each  race  the  most  attractive,  has 
altered  the  character  either  of  the  females  alone,  or  of  both 
sexes.  With  mammals  the  general  rule  appears  to  be  that 
characters  of  all  kinds  are  inherited  equally  by  the  males 
and  females;  we  might,  therefore,  expect  that  with  man- 
kind any  characters  gained  by  the  females  or  by  the  males 
through  sexual  selection  would  commonly  be  transferred  to 
the  offspring  of  both  sexes.  If  any  change  has  thus  been 
effected  it  is  almost  certain  that  the  different  races  would 
be  differently  modified,  as  each  has  its  own  standard  of 
beauty. 

With  mankind,  especially  with  savages,  many  causes 
interfere  with  the  action  of  sexual  selection  as  far  as  the 
bodily  frame  is  concerned.  Civilized  men  are  largely 
attracted  by  the  mental  charms  of  women,  by  their  wealth, 
and  especially  by  their  social  position;  for  men  rarely 
marry  into  a  much  lower  rank.  The  men  who  succeed  in 
obtaining  the  more  beautiful  women  will  not  have  a  better 
chance  of  leaving  a  long  line  of  descendants  than  other 


SECONDARY  SEXUAL  CHARACTERS.  G69 

men  with  plainer  wives,  save  the  few  who  bequeath  their 
fortunes  according  to  primogeniture.  With  respect  to  the 
opposite  form  of  selection,  namely,  of  the  more  attractive 
men  by  the  women,  although  in  civilized  nations  women 
have  free  or  almost  free  choice,  which  is  not  the  case  with 
barbarous  races,  yet  their  choice  is  largely  influenced  by 
the  social  position  and  wealth  of  the  men;  and  the  success 
of  the  latter  in  life  depends  much  on  their  intellectual 
powers  and  energy,  or  on  the  fruits  of  these  same  powers 
in  their  forefathers.  No  excuse  is  needed  for  treating  this 
subject  in  some  detail;  for,  as  the  German  philosopher 
Schopenhauer  remarks,  '^  the  final  aim  of  all  love  intrigues, 
be  they  comic  or  tragic,  is  really  of  more  importance  than 
all  other  ends  in  human  life.  What  it  all  turns  upon  is 
nothing  less  than  the  composition  of  the  next  genera- 
tion. .  .  .  It  is  not  the  weal  or  woe  of  any  one  indi- 
vidual, but  that  oi  the  human  race  to  come,  which  is  here 
at  stake."* 

There  is,  however,  reason  to  believe  that  in  certain  civil- 
ized and  semi-civilized  nations  sexual  selection  has  effected 
something  in  modifying  the  bodily  frame  of  some  of  the 
members.  Many  persons  are  convinced,  as  it  appears  to 
me  with  justice,  that  our  aristocracy,  including  under  this 
term  all  wealthy  families  in  which  primogeniture  has  long 
prevailed,  from  having  chosen  during  many  generations 
from  all  classes  the  more  beautiful  women  as  their  wives, 
have  become  handsomer,  according  to  the  European 
standard,  than  the  middle  classes;  yet  the  middle  classes 
are  placed  under  equally  favorable  conditions  of  life  for 
the  perfect  development  of  the  body.  Cook  remarks  that 
the  superiority  in  personal  appearance  ^^  which  is  observa- 
ble in  the  erees  or  nobles  in  all  the  other  islands  (of  the 
Pacific)  is  found  in  the  Sandwich  Islands ;"  but  this 
may  be  chiefly  due  to  their  better  food  and  manner  of 
life. 

The  old  traveler  Chardin,  in  describing  the  Persians, 
says  their  ''  blood  is  now  highly  refined  by  frequent  inter- 
mixtures with  the  Georgians  and  Circassians,  two  nations 
which  surpass  all  the  world  in  personal  beauty.  There  is 
hardly  a  man  of  rank   in   Persia  who   is  not  born   of   a 

*"  Schopenhauer  and  Darwinism,"  in  "  Jouruftlof  Anthropology," 
Jan.,  1871,  p.  323- 


670  THE  DESCENT  OF  MAN. 

Georgian  or  Circassian  mother."  He  adds  that  they  inherit 
their  beauty,  ^^not  from  their  ancestors,  for  without  the 
above  mixture  the  men  of  rank  in  Persia,  who  are  descend- 
ants of  the  Tartars,  would  be  extremely  ugly."*  Here  is 
a  more  curious  case;  the  priestesses  who  attended  the  temple 
of  Venus  Erycina  at  San  Giuliano,  in  Sicily,  were  selected 
for  their  beauty  out  of  the  whole  of  Greece;  they  were  not 
vestal  virgins,  and  Quatrefages,f  who  states  the  foregoing 
fact,  says  that  the  women  of  San  Giuliano  are  now  famous 
as  the  most  beautiful  in  the  island,  and  are  sought  by 
artists  as  models.  But  it  is  obvious  that  the  evidence  in 
all  the  above  cases  is  doubtful. 

The  following  case,  though  relating  to  savages,  is  well 
worth  giving  from  its  curiosity.  Mr.  Winwood  Reade  in- 
forms me  that  the  Jollofs,  a  tribe  of  negroes  on  the  west 
coast  of  Africa,  **are  remarkable  for  their  uniformly  fine 
appearance."  A  friend  of  his  asked  one  of  these  men: 
"  How  is  it  that  every  one  whom  I  meet  is  so  fine  looking, 
not  only  your  men,  but  your  women?"  The  Jollof  an- 
swered: *'It  is  very  easily  explained;  it  has  always  been 
our  custom  to  pick  out  our  worst-looking  slaves  and  to 
sell  them."  It  need  hardly  be  added  that  with  all  savages 
female  slaves  serve  as  concubines.  That  this  negro  should 
have  attributed,  whether  rightly  or  wrongly,  the  fine 
appearance  of  his  tribe  to  the  long-continued  elimination 
of  the  ugly  women  is  not  so  surprising  as  it  may  at  first 
appear:  for  I  have  elsewhere  shownj  that  negroes  fully 
appreciate  the  importance  of  selection  in  the  breeding  of 
their  domestic  animals,  and  I  could  give  from  Mr.  Reade 
additional  evidence  on  this  head. 

The  Causes  Which  Prevent  or  Cliech  the  Action  of  Sexual 
Selection  with  Savages. — The  chief  causes  are,  first  so- 
called  communal  marriages  or  promiscuous  intercourse  ; 
early  betrothals;  and,  lastly,  the  low  estimation  in  which 

*  These  quotations  are  taken  from  Lawrence  ("  Lectures  on  Physi- 
ology," etc.,  1822,  p.  393),  who  attributes  the  beauty  of  the  upper 
classes  in  England  to  the  men  having  long  selected  the  more  beau- 
tiful women. 

f  •' Anthropologic,"  "Revue  des  Cours  Scientifique,"  Oct.,  1868, 
p.  721. 

f'The  Variation  of  Animals  and  Plants  under  DomesticatioL . *' 
vol.  i,  p.  207. 


SECONDARY  SEXUAL  CUABAGTERS.  671 

secondly,  the  consequences  of  female  infanticide;  thirdly, 
women  are  held  as  mere  slaves.  These  four  points  must 
be  considered  in  some  detail. 

It  is  obvious  that  as  long  as  the  pairing  of  man  or  of 
any  otlier  animal  is  left  to  mere  chance,  witli  no  choice 
exerted  by  either  sex,  there  can  be  no  sexual  selection;  and 
no  eifect  will  be  produced  on  the  offspring  by  certain  indi- 
viduals having  had  an  advantage  over  others  in  their  court- 
ship. Now,  it  is  asserted  that  there  exist  at  the  present  da^ 
tribes  which  practice  what  Sir  J.  Lubbock  by  courtesy 
calls  communal  marriages;  that  is,  all  the  men  and  women 
in  the  tribe  are  Imsbands  and  wives  to  one  another.  The 
licentiousness  of  many  savages  is  no  doubt  astonishing,  but 
it  seems  to  me  that  more  evidence  is  requisite,  before  we 
fully  admit  that  their  intercourse  is  in  any  case  promiscu- 
ous. Nevertheless,  all  those  who  have  most  closely  studied 
the  subject,*  and  whose  judgment  is  wortli  much  more 
than  mine,  believe  that  communal  marriage  (this  ex- 
pression being  variously  guarded)  was  the  original 
and  universal  form  throughout  the  world,  including 
therein  the  intermarriage  of  brothers  and  sisters. 
The  late  Sir  A.  Smith,  who  had  traveled  widely 
in  S.  Africa,  and  knew  much  about  the  habits  of 
savages  there  and  elsewhere,  expressed  to  me  the  strongest 
opinion  that  no  race  exists  in  which  woman  is  considered 
as  the  property  of  the  community.  I  believe  that  his  judg- 
ment was  largely  determined  by  what  is  implied  by  the 
term  marriage.  Throughout  the  following  discussion  I 
use  the  term  in  the  same  sense  as  when  naturalists  speak  of 
animals  as  monogamous,  meaning  thereby  that  the  male  is 
accepted  by  or  chooses  a  single  female,  and  lives  with  her 

*Sir  J.  Lubbock,  "  Tlie  Origin  of  Civilization,"  1870,  chap,  iii, 
especially  pp.  60-67.  Mr.  M'Lennan,  in  bis  extremely  valuable 
work  on  "  Primitive  Marriage,"  1865,  p.  163,  speaks  of  tbe  union  of 
the  sexes  "in  tbe  earliest  times  as  loose,  transitory,  and  in  some 
degree  promiscuous."  Mr.  M'Lennan  and  Sir  J.  Lubbock  bave  col- 
lected mucb  evidence  on  tbe  extreme  licentiousness  of  savages  at 
tbe  present  time.  Mr,  L.  H.  Morgan,  in  bis  interesting  memoir  on 
tbe  classificatory  system  of  relationsbip  ("  Proc.  American  Acad,  of 
Sciences,"  vol.  vii,  Feb.,  1868.  p.  475),  concludes  tbat  polygamy 
and  all  forms  of  marriage  during  primeval  times  were  essentially 
unknown.  It  appears,  also,  from  Sir  J.  Lubbock's  work,  tbat  Bacb- 
ofen  likewise  believes  tbat  communal  intercourse  originally  pre- 
vailed. 


672  THE  DESCENT  OF  MAN. 

either  during  the  breeding-season  or  for  the  whole  year, 
keeping  possession  of  her  by  the  law  of  might;  or,  as  when 
they  speak  of  a  polygamous  species,  meaning  that  the  male 
lives  with  several  females.  This  kind  of  marriage  is  all 
that  concerns  ns  here,  as  it  suffices  for  the  work  of  sexual 
selection.  But  I  know  that  some  of  the  writers  above 
referred  to  imply  by  the  term  marriage  a  recognized  right 
protected  by  the  tribe. 

The  indirect  evidence  in  favor  of  the  belief  of  the  former 
prevalence  of  communal  marriages  is  strong,  and  rests 
chiefly  on  the  terms  of  relationship  which  are  employed 
between  the  members  of  the  same  tribe,  implying  a  con- 
nection with  the  tribe,  and  not  with  either  parent.  But 
the  subject  is  too  large  and  complex  for  even  an  abstract  to 
be  here  given,  and  I  will  confine  myself  to  a  few  remarks.  It 
is  evident  in  the  case  of  such  marriages,  or  where  the  mar- 
riage tie  is  very  loose,  that  the  relationship  of  the  child  to  its 
father  cannot  be  known.  But  it  seems  almost  incredible 
that  the  relationship  of  the  child  to  its  mother  should  ever 
be  completely  ignored,  especially  as  the  women  in  most 
savage  tribes  nurse  their  infants  for  a  long  time.  Accord- 
ingly, in  many  cases  the  lines  of  descent  are  traced  through 
the  mother  alone,  to  the  exclusion  of  the  father.  But  in 
other  cases  the  terms  employed  express  a  connection  with 
the  tribe  alone,  to  the  exclusion  even  of  the  mother.  It 
seems  possible  that  the  connection  between  the  related 
members  of  the  same  barbarous  tribe,  exposed  to  all  sorts 
of  danger,  might  be  so  much  more  important,  owing  to  the 
need  of  mutual  protection  and  aid,  than  that  between  the 
mother  and  her  child,  as  to  lead  to  the  sole  use  of  terms 
expressive  of  the  former  relationships;  but  Mr.  Morgan  is 
convinced  that  this  view  is  by  no  means  sufficient. 

The  terms  of  relationship  used  in  different  parts  of  the 
world  may  be  divided,  according  to  the  author  just  quoted, 
into  two  great  classes — the  classificatory  and  descriptive — 
the  latter  being  employed  by  us.  It  is  the  classificatory 
system  which  so  strongly  leads  to  the  belief  that  communal 
and  other  extremely  loose  forms  of  marriage  were  originally 
universal.  But,  as  far  as  I  can  see,  there  is  no  necessity  on 
this  ground  for  believing  in  absolutely  promiscuous  inter- 
course; and  I  am  glad  to  find  that  this  is  Sir  J.  Lubbock's 
view.  Men  and  women,  like  many  of  the  lower  animals, 
might  formerly  have  entered  into  strict  though  temporary 


SECONDARY  SKXUAL  CHARACTERS.  673 

unions  for  each  birth,  and  in  this  case  nearly  as  much  con- 
fusion would  have  arisen  in  the  term  of  relationship  as  in 
the  case  of  promiscuous  intercourse.  As  far  as  sexual 
selection  is  concerned  all  that  is  required  is  that  choice 
should  be  exerted  before  the  parents  unite,  and  it  signifies 
little  whether  the  unions  last  for  life  or  only  for  a  season. 

Besides  the  evidence  derived  from  the  terms  of  relation- 
ship, other  lines  of  reasoning  indicate  the  former  wide  prev- 
alence of  communal  marriage.  Sir  J.  Lubbock  accounts* 
for  the  strange  and  widely  extended  habit  of  exogamy — 
that  is,  the  men  of  one  tribe  taking  wives  from  a  distinct 
tribe — by  communism  having  been  the  original  form  of 
intercourse;  so  that  a  man  never  obtained  a  wife  for  him- 
self unless  he  captured  her  from  a  neighboring  and  hostile 
tribe,  and  then  she  would  naturally  have  become  his  sole 
and  valuable  property.  Thus  the  practice  of  capturing 
wives  might  have  arisen;  and  from  the  honor  so  gained  it 
might  ultimately  have  become  the  universal  habit.  Ac- 
cording to  Sir  J.  Lubbock,*  we  can  also  thus  understand 
^'^the  necessity  of  expiation  for  marriage  as  an  infringe- 
ment of  tribal  rites,  since,  according  to  old  ideas,  a  man 
had  no  right  to  appropriate  to  himself  that  which  belonged 
to  the  whole  tribe."  Sir  J.  Lubbock  further  gives  a 
curious  body  of  facts  showing  that  in  old  times  high  honor 
was  bestowed  on  women  who  were  utterly  licentious;  and 
this,  as  he  explains,  is  intelligible,  if  we  admit  that  pro- 
miscuous intercourse  was  the  aboriginal,  and  therefore  long 
revered  custom  of  the  tribe,  f 

Although  the  manner  of  development  of  the  marriage- 
tie  is  an  obscure  subject,  as  we  may  infer  from  the  diver- 
gent opinions  on  several  points  between  the  three  authors 
who  have  studied  it  most  closely,  namely,  Mr.  Morgan, 
Mr.  M'Lennan,  and  Sir  J.  Lubbock,  yet  from  the  fore- 
going and  several  other  lines  of  evidence  it  seems  probable  J; 

*  ''  Address  to  British  Association  on  the  Social  and  Religious  Con- 
dition of  the  Lower  Races  of  Man,"  1870,  p.  20. 

f  "  Origin  of  Civilization,"  1870,  p.  86.  In  the  several  works  above 
quoted,  there  will  be  found  copious  evidence  on  relationship  through 
the  females  alone,  or  with  the  tribe  alone. 

^Mr.  C.  Staniland  Wake  argues  strongly  ("Anthropologic," 
March,  1874,  p.  197)  against  the  views  held  by  these  three  writers 
on  the  former  prevalence  of  almost  promiscuous  intercourse;  and  he 
thinks  that  the  classificator^  system  of  relationship  can  be  other- 
wise explainecj. 


674  THE  DESCENT  OF  MAN. 

that  the  habit  of  marriage,  in  any  strict  sense  of  the  word, 
has  been  gradually  developed;  and  that  almost  promiscu- 
ous or  very  loose  intercourse  was  once  extremely  common 
throughout  the  world.  Nevertheless,  from  the  strength  of 
the  feeling  of  jealousy  all  through  the  animal  kingdom,  as 
well  as  from  the  analogy  of  the  lower  animals,  more  partic- 
ularly of  those  which  come  nearest  to  man,  I  cannot 
believe  that  absolutely  promiscuous  intercourse  prevailed  in 
times  past,  shortly  before  man  attained  to  his  present  rank 
in  the  zoological  scale.  Man,  as  I  have  attempted  to  show, 
is  certainly  descended  from  some  ape-like  creature.  With 
the  existing  Quadrumana,  as  far  as  their  habits  are  known, 
the  males  of  some  species  are  monogamous,  but  live  during 
only  a  part  of  the  year  with  the  females;  of  this  the  orang 
seems  to  afford  an  instance.  Several  kinds,  for  example 
some  of  the  Indian  and  American  monkeys,  are  strictly 
monogamous,  and  associate  all  the  year  round  with  their 
wives.  Others  are  polygamous,  for  example  the  gorilla 
and  several  American  species,  and  each  family  lives  sepa- 
rate. Even  when  this  occurs,  the  families  inhabiting  the 
same  district  are  probably  somewhat  social;  the  chimpanzee, 
for  instance,  is  occasionally  met  with  in  large  bands. 
Again,  other  species  are  polygamous,  but  several  males, 
each  with  his  own  females,  live  associated  in  a  body,  as 
with  several  species  of  baboons.*  We  may  indeed  conclude 
from  what  we  know  of  the  jealousy  of  all  male  quadrupeds 
armed,  as  many  of  them  are,  with  special  weapons  for  bat- 
tling with  their  rivals,  that  promiscuous  intercourse  in  a 
state  of  nature  is  extremely  improbable.  The  pairing  may 
not  last  for  life,  but  only  for  each  birth;  yet  if  the  males 
which  are  the  strongest  and  best  able  to  defend  or  other- 
wise assist  their  females  and  young,  were  to  select  the  more 
attractive  females,  this  would  suffice  for  sexual  selection. 

Therefore,  looking  far  enough  back  in  the  stream  of 
time,  and,  judging  from  the  social  habits  of  man  as  he  now 
exists,  the  most  probable  view  is  that  he  aboriginally  lived 
in  small  communities,  each  with  a  single  wife,  or  if  power- 
ful with  several,  whom  he  jealously  guarded  against  all 

*Brehin  ("  lUust.  Thierleben,"  B,  i,  p.  77)  says  Cynocephalus 
Jiamadryas  Uvea  in  great  troops  containing  twice  as  many  adult 
females  as  adult  males.  See  Rengger  on  American  polygamous 
species,  and  Owen  ("  Anat.  of  Vertebrates,"  vol.  iii,  p.  776)  on  Amer- 
ican monogauaous  species.     Other  references  might  be  added. 


SECONDARY  SEXUAL  CHARACTERS,  675 

other  men.  Or  he  may  not  have  been  a  social  animal,  and 
yet  have  lived  with  several  wives,  like  the  gorilla:  for  all 
the  natives  **  agree  that  but  one  adult  male  is  seen  in  a 
band;  when  the  young  male  grows  up  a  contest  takes  place 
for  mastery,  and  the  strongest,  by  killing  and  driving  out 
the  others,  establishes  himself  as  the  head  of  the  com- 
munity."* The  younger  males,  being  thus  expelled  and 
wandering  about,  would,  when  at  last  successful  in  finding 
a  partner,  prevent  too  close  interbreeding  within  the  limits 
of  the  same  family. 

Although  savages  are  now  extremely  licentious,  and, 
although  communal  marriages  may  formerly  have  largely 
prevailed,  yet  many  tribes  practice  some  form  of  marriage, 
but  of  a  far  more  lax  nature  than  that  of  civilized  nations. 
Polygamy,  as  just  stated,  is  almost  universally  followed  by 
the  leading  men  in  every  tribe.  Nevertheless  there  are  tribes, 
standing  almost  at  the  bottom  of  the  scale,  which  are 
strictly  monogamous.  This  is  the  case  with  the  Veddahs 
of  Ceylon;  they  have  a  saying,  according  to  Sir  J.  Lub- 
bock,! "  that  death  alone  can  separate  husband  and  wife.'' 
An  intelligent  Kandyan  chief,  of  course  a  polygamist, 
"  was  perfectly  scandalized  at  the  utter  barbarism  of  living 
with  only  one  wife,  and  never  parting  until  separated  by 
death."  *'  It  was,"  he  said,  *^  just  like  the  Wanderoo  mon- 
keys." Whether  savages  who  now  enter  into  some  form  of 
marriage,  either  polygamous  or  monogamous,  have  re- 
tained this  habit  from  primeval  times,  or  whether  they 
have  returned  to  some  form  of  marriage,  after  passing 
through  a  stage  of  promiscuous  intercourse,  I  will  not 
pretend  to  conjecture. 

Infanticide. — This  practice  is  now  very  common  through- 
out the  world,  and  there  is  reason  to  believe'  that  it  pre- 
vailed much  more  extensively  during  former  times.  |  Bar- 
barians find  it  difficult  to  support  themselves  and  their 
children,  and  it  is  a  simple  plan  to  kill  their  infants.  In 
South  America  some  tribes,  according  to  Azara,  formerly 

*Dr.  Savage,  in  "Boston  Journal  of  Nat.  Hist.,"  vol.  v,  1845-47, 
p.  423. 

t  "  Prehistoric  Times,"  1869,  p.  424. 

I  Mr.  M'Lennan,  "Primitive  Marriage,"  1865.  See  especially  on 
exogamy  and  infanticide,  pp.  130,  138,  165. 


676  THE  DESCENT  OF  MAN. 

destroyed  so  many  infants  of  both  sexes  that  they  were  on 
the  point  of  extinction.  In  the  Polynesian  IsUmds  women 
have  been  known  to  kill  from  four  or  five,  to  even  ten  of 
their  children;  and  Ellis  could  not  find  a  single  woman 
who  had  not  killed  at  least  one.  In  a  village  on  the 
eastern  frontier  of  India  Col.  McCulloch  found  not  a 
single  female  child.  Wherever  infanticide*  prevails  the 
struggle  for  existence  will  be  in  so  far  less  severe,  and  all 
the  members  of  the  tribe  will  have  an  almost  equally  good 
chance  of  rearing  their  few  surviving  children.  In  most 
cases  a  larger  number  of  female  than  of  male  infants  are 
destroyed,  for  it  is  obvious  that  the  latter  are  of  more  value 
to  the  tribe,  as  they  will,  when  grown  up,  aid  in  defending 
it,  and  can  support  themselves.  But  the  trouble  experienced 
by  the  women  in  rearing  children,  their  consequent  loss 
of  beauty,  the  higher  estimation  set  on  them  when  few, 
and  their  happier  fate,  are  assigned  by  the  women  them- 
selves, and  by  various  observers,  as  additional  motives  for 
infanticide. 

When,  owing  to  female  infanticide,  the  women  of  a  tribe 
were  few,  the  habit  of  capturing  wives  from  neighboring 
tribes  would  naturally  arise.  Sir  J.  Lubbock,  however,  as 
we  have  seen,  attributes  the  practice  in  chief  part  to  the 
former  existence  of  communal  marriage,  and  to  the  men 
having  consequently  captured  women  from  other  tribes  to 
hold  as  their  sole  property.  Additional  causes  might  be 
assigned,  such  as  the  communities  being  very  small,  in 
which  case,  marriageable  women  would  often  be  deficient. 
That  the  habit  was  most  extensively  practiced  during 
former  times,  even  by  the  ancestors  of  civilized  nations,  is 
clearly  shown  by  the  preservation  of  many  curious  customs 
and  ceremonies,  of  which  Mr.  McLennan  has  given  an 
interesting  account.  In  our  own  marriages  the  ''best 
man  "  seems  originally  to  have  been  the  chief  abettor  of 
the  bridegroom  in  the  act  of  capture.  Now,  as  long  as 
men  habitually  procured  their  wives  through  violence  and 

*Dr.  Gerland  ("  Ueber  das  Aussterben  der  Naturvolker,"  1868) 
Las  collected  much  information  on  infanticide,  see  especially  ss.  27, 
51,  54.  Azara  ("Voyages,"  etc.,  torn,  ii,  pp.  94,  116)  enters  in  detail 
on  the  motives.  See  also  M'Lennan  (ibid,  p.  139)  for  cases  in  India. 
In  the  former  reprints  of  the  2d  edition  of  this  lx)ok  an  incorrect 
quotation  from  Sir  G.  Grey  was  unfortunately  given  in  the  above 
passage  and  has  now  been  removed  from  the  text. 


SECONDARY  SEXUAL  GUARACTERS,  67t 

craft,  they  would  have  beeti  glad  to  seize  on  any  woman, 
and  would  not  have  selected  the  more  attractive  ones.  But 
as  Soon  as  the  practice  of  procuring  wives  from  a  distinct 
tribe  was  effected  through  barter,  as  now  occurs  in  many 
pUices,  the  more  attractive  women  would  generally  have 
been  purchased.  The  incessant  crossing,  however,  between 
tribe  and  tribe,  which  necessarily  follows  from  any  form  of 
this  habit,  would  tend  to  keep  all  the  people  inhabiting  the 
same  country  nearly  uniform  in  character;  and  this  would 
interfere  with  the  power  of  sexual  selection  in  differentiat- 
ing the  tribes. 

The  scarcity  of  women,  consequent  on  female  infanti- 
cide, leads,  also,  to  another  practice,  that  of  polyandry, 
still  common  in  several  parts  of  the  world,  and  which 
formerly,  as  Mr.  McLennan  believes,  prevailed  almost  uni- 
versfilly;  but  this  latter  conclusion  is  doubted  by  Mr. 
Morgan  and  Sir  J.  Lubbock.*  Whenever  two  or  more  men 
are  compelled  to  marry  one  women  it  is  certain  that  all  the 
women  of  the  tribe  will  get  married,  and  there  will  be  no 
selection  by  the  men  of  the  more  attractive  women.  But, 
under  these  circumstances,  the  women  no  doubt  will  have 
the  power  of  choice,  and  will  prefer  the  more  attractive 
men.  Azara,  for  instance,  describes  how  carefully  a  Guana 
woman  bargains  for  all  sorts  of  privileges  before  accepting 
some  one  or  more  husbands;  and  the  men  in  consequence 
take  unusual  care  of  their  personal  appearance.  So  among 
the  Todas  of  India,  who  practice  polyandry,  the  girls  can 
accept  or  refuse  any  man.f  A  very  ugly  man  in  these 
cases  would,  perhaj^s,  altogether  fail  in  getting  a  wife, 
or  get  one  later  in  life ;  but  the  handsomer  men, 
although  more  successful  in  obtaining  wives,  would  not, 
as  far  as  we  can  see,  leave  more  offspring  to  inherit 
their  beauty  than  the  less  handsome  husbands  of  the  same 
women. 

Early  Betrothals  and  Slavery  of  Women. — With  many 
savages  it  is  the  custom  to  betroth  the  females  while  mere 
infants  ;   and   this  would    effectually  prevent  preference 

*  "  Primitive  Marriage,"  p.  208;  Sir  J.  Lubbock,  "  Origin  of  Civili- 
zation," p.  100.  See  also  Mr.  Morgan,  loc.  cit.,  on  the  former  preva- 
lence of  polyandry. 

f  Azara,  "Voyages,"  etc.,  tom.  ii,  pp.  92-95,  Colonel  Marshall 
"  Among  the  Todas,"  p.  212. 


678  ^HE  DESCENT  OF  MAN, 

being  exerted  on  either  side  according  to  personal  appear- 
ance. But  it  would  not  prevent  the  more  attractive  women 
from  being  afterward  stolen  or  taken  by  force  from  their 
husbands  by  the  more  powerful  men;  and  this  often  hap- 
pens in  Australia,  America  and  elsewliere.  The  same  con- 
sequences with  reference  to  sexual  selection  would  to  a 
certain  extent  follow,  when  women  are  valued  almost 
solely  as  slaves  or  beasts  of  burden,  as  is  the  case  with 
many  savages.  The  men,  however,  at  all  times  would 
prefer  the  handsomest  slaves,  according  to  their  standard  of 
beauty. 

We  thus  see  that  several  customs  prevail  with  savages 
which  must  greatly  interfere  with,  or  completely  stop,  the 
action  of  sexual  selection.  On  the  other  hand,  the  con- 
ditions of  life  to  which  savages  are  exposed,  and  some  of 
their  habits,  are  favorable  to  natural  selection;  and  this 
comes  into  play  at  the  same  time  with  sexual  selection. 
Savages  are  known  to  suffer  severely  from  recurrent  famines; 
they  do  not  increase  their  food  by  artificial  means;  they 
rarely  refrain  from  marriage,*  and  generally  marry  while 
young.  Consequently  they  must  be  subjected  to  occasional 
hard  struggles  for  existence,  and  the  favored  individuals 
will  alone  survive. 

At  a  very  early  period,  before  man  attained  to  his  present 
rank  in  the  scale,  many  of  his  conditions  would  be  differ- 
ent from  what  now  obtains  among  savages.  Judging  from 
the  analogy  of  the  lower  animals,  he  would  then  either  live 
with  a  single  female,  or  be  a  polygamist.  The  most  pow- 
erful and  able  males  would  succeed  best  in  obtaining  attrac- 
tive females.  They  would  also  succeed  best  in  the  general 
struggle  for  life,  and  in  defending  their  females,  as  well  as 
their  offspring,  from  enemies  of  all  kinds.  At  this  early 
period  the  ancestors  of  man  would  not  be  sufficiently  ad- 
vanced in  intellect  to  look  forward  to  distant  contingencies; 
they  would  not  foresee  that  the  rearing  of  their  children, 
especially  their  female  children,  would  make  the  struggle 
for  life  severer  for  the  tribe.  They  would  be  governed 
more  by  their  instincts  and  less  by  their  reason  than  are 

*Burchell  says  ("  Travels  in  S.  Africa,"  vol.  ii,  1824.  p.  58),  that 
among  the  wild  nations  of  Southern  Africa,  neither  men  nor  women 
ever  pass  their  lives  in  a  state  of  celibacy.  Azara  ("  Voyages  dans 
I'Amerique  Merid.,"  torn,  ii,  1809,  p.  21)  makes  precisely  the  same 
remark  in  regard  to  the  wild  Indians  of  South  America. 


SECOJ^DARt  SEXUAL  OHARACTEHS,  679 

savages  at  the  present  day.  They  would  not  at  that 
period  have  partially  lost  one  of  the  strongest  of  all 
instincts  common  to  all  lower  animals,  namely,  the  love  of 
their  young  offspring ;  and  consequently  they  would  not 
have  practiced  female  infanticide.  Women  would  not 
have  been  thus  rendered  scarce,  and  polyandry  would  not 
have  been  practiced;  for  hardly  any  other  cause  except  the 
scarcity  of  women  seems  sufficient  to  break  down  the  nat- 
ural and  widely  prevalent  feeling  of  jealousy  and  the  desire 
of  each  male  to  possess  a  female  for  himself.  Polyandry 
would  be  a  natural  stepping-stone  to  communal  marriages 
or  almost  promiscuous  in tercoui-se;  though  the  best  authori- 
ties believe  that  this  latter  habit  preceded  polandry. 
During  primordial  times  there  would  be  no  early  betroth- 
als, for  this  implies  foresight.  Nor  would  women  be 
valued  merely  as  useful  slaves  or  beasts  of  burden.  Both 
sexes,  if  the  females  as  well  as  the  males  were  permitted  to 
exert  any  choice,  would  choose  their  partners  not  for 
mental  charms,  or  property,  or  social  position,  but  almost 
solely  from  external  appearance.  All  the  adults  would 
marry  or  pair,  and  all  the  offspring,  as  far  as  that  was 
possible,  would  be  reared;  so  that  the  struggle  for  exist- 
ence would  be  periodically  excessively  severe.  Thus,  during 
these  times  all  the  conditions  for  sexual  selection  would 
have  been  more  favorable  than  at  a  later  period,  when  man 
had  advanced  in  his  intellectual  powers  but  had  retro- 
graded in  his  instincts.  Therefore,  whatever  influence 
sexual  selection  may  have  had  in  producing  the  differences 
between  the  races  of  man  and  between  man  and  the  higher 
Quadrumana,  this  influence  would  have  been  more  power- 
ful at  a  remote  period  than  at  the  present  day,  though 
probably  not  yet  wholly  lost. 

The  Manner  of  Action  of  Sexual  Selection  with  Man- 
kind,— With  primeval  man  under  the  favorable  conditions 
just  stated,  and  with  those  savages  who  at  the  present  time 
enter  into  any  marriage  tie,  sexual  selection  has  probably 
acted  in  the  following  manner,  subject  to  greater  or  less 
interference  from  female  infanticide,  early  betrothals,  etc. 
The  strongest  and  most  vigorous  men — those  who  could 
best  defend  and  hunt  for  their  families,  who  were  pro- 
vided with  the  best  weapons  and  possessed  the  most  prop- 
erty, such  as  a  large  number  of  dogs  or  other  animals — 


680  "THE  DESCENT  OF  MAN. 

would  Succeed  in  rearing  a  greater  average  number  of  off- 
spring than  the  weaker  and  poorer  members  of  the  same 
tribe.  There  can,  also,  be  no  doubt  that  such  men  would 
generally  be  able  to  select  the  more  attractive  women.  At 
present  the  chiefs  of  nearly  every  tribe  throughout  the 
world  succeed  in  obtaining  more  than  one  wife.  I  hear 
from  Mr.  Mantell  tliat  until  recently  almost  every  girl  in 
New  Zealand  who  was  pretty  or  promised  to  be  pretty  was 
tapu  to  some  chief.  With  the  Kafirs,  as  Mr.  C.  Hamilton 
states,*  **tlie  chiefs  generally  have  the  pick  of  the  women 
for  many  miles  round  and  are  most  persevering  in  estab- 
lishing or  confirming  their  privilege."  We  have  seen  that 
each  race  has  its  own  style  of  beauty,  and  we  know  that  it 
is  natural  to  man  to  admire  each  characteristic  point  in 
his  domestic  animals,  dress,  ornaments  and  personal  appear- 
ance when  carried  a  little  beyond  the  average.  If,  then, 
the  several  foregoing  propositions  be  admitted,  and  I 
cannot  see  that  they  are  doubtful,  it  would  be  an  inex- 
plicable circumstance  if  the  selection  of  the  more  attractive 
women  by  the  more  powerful  men  of  each  tribe  who  would 
rear  on  an  average  a  greater  number  of  children  did  not 
after  the  lapse  of  many  generations  somewhat  modify  the 
character  of  the  tribe. 

When  a  foreign  breed  of  our  domestic  animals  is  intro- 
duced into  a  new  country,  or  when  a  native  breed  is  long 
and  carefully  attended  to,  either  for  use  or  ornament,  it  is 
found  after  several  generations  to  have  undergoue  a  greater 
or  less  amount  of  change  whenever  the  means  of  compari- 
son exist.  This  follows  from  unconscious  selection  during 
a  long  series  of  generations — that  is,  the  preservation  of  the 
most  approved  individuals — without  any  wish  or  expecta- 
tion of  such  a  result  on  the  part  of  the  breeder.  So  again, 
if  during  many  years  two  careful  breeders  rear  animals  of 
the  same  family,  and  do  not  compare  them  together  or 
with  a  common  standard,  the  animals  are  found  to  have 
become,  to  the  surprise  of  their  owners,  slightly  different,  f 
Each  breeder  has  impressed,  as  Von  Nathusius  well  ex- 
presses it,  the  character  of  his  own  mind — his  own  taste 
and  judgment — on  his  animals.     What  reason,  then,  can 

*  "Anthropological  Review,"  Jan.,  1870,  p.  xvi. 
f  "  The  Variation  of  Animals  and  Plants  under  Domestication,"  vol. 
ii,  pp.  210-217. 


SECONDARY  SEXUAL  CHARACTERS.  681 

be  assigned  why  similar  results  should  not  follow  from  the 
long-continued  selection  of  the  most  admired  women  by 
those  men  of  each  tribe  who  were  able  to  rear  the  greatest 
number  of  children?  This  would  be  unconscious  selection, 
for  an  effect  would  be  produced,  independently  of  any  wish 
or  expectation  on  the  part  of  the  men  who  preferred  cer- 
tain women  to  others. 

Let  us  suppose  the  members  of  a  tribe,  practicing  som& 
form  of  marriage,  to  spread  over  an  unoccupied  continent, 
they  would  soon  split  up  into  distinct  hordes,  separated 
from  each  other  by  various  barriers,  and  still  more  effectu- 
ally by  the  incessant  wars  between  all  barbarous  nations. 
The  hordes  would  thus  be  exposed  to  slightly  different 
conditions  and  habits  of  life  and  would  sooner  or  later  come 
to  differ  in  some  small  degree.  As  soon  as  this  occurred, 
each  isolated  tribe  would  form  for  itself  a  slightly  different 
standard  of  beauty;*  and  then  unconscious  selection  would 
come  into  action  through  the  more  powerful  and  leading 
men  preferring  certain  women  to  others.  Thus  the  dif- 
ferences between  the  tribes,  at  first  very  slight,  would 
gradually  and  inevitably  be  more  or  less  increased. 

With  animals  in  a  state  of  nature,  many  characters 
proper  to  the  males,  such  as  size,  strength,  special  weapons, 
courage  and  pugnacity,  have  been  acquired  through  the 
law  of  battle.  The  semi-human  progenitors  of  man,  like 
their  allies  the  Q.uadrumana,  will  almost  certainly  have 
been  thus  modified;  and,  as  savages  still  fight  for  the  pos- 
session of  their  women,  a  similar  process  of  selection  has 
probably  gone  on  in  a  greater  or  less  degree  to  the  present 
day.  Other  characters  proper  to  the  males  of  the  lower 
animals,  such  as  bright  colors  and  various  ornaments,  have 
been  acquired  by  the  more  attractive  males  having  bee-, 
preferred  by  the  females.  There  are,  however,  exceptiouid 
cases  in  which  the  males  are  the  selectors,  instead  of  having 
been  the  selected.  We  recognize  such  cases  by  the  females 
being  more  highly  ornamented  than  the  males — their  orna- 
mental characters  having  been  transmitted  exclusively  or 

*  An  ingenious  writer  argues,  from  a  comparison  of  the  pictures  of 
Raphael,  Rubens,  and  modern  French  artists,  that  the  idea  of  beauty 
is  not  absolutely  the  same  even  throughout  Europe;  see  the  "  Lives 
of  Haydn  and  Mozart,"  by  Bom  bet  (otherwise  M.  Beyle),  English 
trauslat. ,  p.  278. 


682  THE  DESCENT  OF  MAN. 

chiefly  to  their  female  offspring.  One  such  case  has  been 
described  in  the  order  to  which  man  belongs,  that  of  the 
Rhesus  monkey. 

Man  is  more  powerful  in  body  and  mind  than  woman, 
and  in  the  savage  state  he  keeps  her  in  a  far  more  abject 
state  of  bondage  than  does  the  male  of  any  other  animal; 
therefore  it  is  not  surprising  that  he  should  have  gained 
the  power  of  selection.  Women  are  everywhere  conscious 
of  the  value  of  their  own  beauty;  and  when  they  have  the 
means,  they  take  more  delight  in  decorating  themselves 
with  all  sorts  of  ornaments  than  do  men.  They  borrow 
the  plumes  of  male  birds,  with  which  nature  has  decked 
this  sex  in  order  to  charm  the  females.  As  women  have 
long  been  selected  for  beauty,  it  is  not  surprising  that  some 
of  their  successive  variations  should  have  been  transmitted 
exclusively  to  the  same  sex;  consequently  that  they  should 
have  transmitted  beauty  in  a  somewhat  higher  degree  to 
their  female  than  to  their  male  offspring,  and  thus  have 
become  more  beautiful,  according  to  general  opinion,  than 
men.  Women,  however,  certainly  transmit  most  of  their 
characters,  including  some  beauty,  to  their  offspring  of  both 
sexes;  so  that  the  continued  preference  by  the  men  of  each 
race  for  the  more  attractive  women,  according  to  their 
standard  of  taste,  will  have  tended  to  modify  in  the  same 
manner  all  the  individuals  of  both  sexes  belonging  to  the 
race. 

With  respect  to  the  other  form  of  sexual  selection  (which 
with  the  lower  animals  is  much  the  more  common),  namely, 
when  the  females  are  the  selectors,  and  accept  only  those 
males  which  excite  or  charm  them  most,  we  have  reason  to 
believe  that  it  formerly  acted  on  our  progenitors.  Man  in 
all  probability  owes  his  beard,  and  perhaps  some  other  char- 
acters, to  inheritance  from  an  ancient  progenitor  who  thus 
gained  his  ornaments.  But  this  form  of  selection  may 
have  occasionally  acted  during  later  times;  for  in  utterly 
barbarous  tribes  the  women  have  more  power  in  choosing, 
rejecting  and  tempting  their  lovers,  or  of  afterward  chang- 
ing their  husbands  than  might  liave  been  expected.  As 
this  is  a  point  of  some  importance,  I  will  give  in  detail 
such  evidence  as  I  have  been  able  to  collect. 

Hearne  describes  how  a  woman  in  one  of  the  tribes  of 
Art^tic  America  repeatedly  ran  away  from  her  husband  and 
joined  her  lover;  and  with  the  Charruas  of  South  America^ 


BECONDARY  SEXUAL  CHARACTERS.  683 

according  to  Azara,  divorce  is  quite  optional.  Among  the 
Abipones,  a  man  on  choosing  a  wife  bargains  with  the  parents 
about  the  price.  But  "  it  frequently  happens  that  the  girl 
rescinds  what  has  been  agreed  upon  between  the  parents 
and  the  bridegroom,  obstinately  rejecting  the  very  men- 
tion of  marriage. ^^  She  often  runs  away,  hides  herself  and 
thus  eludes  the  bridegroom.  Capt.  Musters,  who  lived  with 
the  Patagonians,  says  that  their  marriages  are  always 
settled  by  inclination;  *^  if  the  parents  make  a  match  con- 
trary to  the  daughter's  will,  she  refuses  and  is  never  com- 
pelled to  comply. '^  In  Terra  del  Fuego  a  young  man  first 
obtains  the  consent  of  the  parents  by  doing  them  some 
service,  and  then  he  attempts  carry  off  the  girl;  ^^butif  she 
is  unwilling,  she  hides  herself  in  the  woods  until  her  admirer 
is  heartily  tired  of  looking  for  her  and  gives  up  the  pur- 
suit; but  this  seldom  happens."  In  the  Fiji  Islands  the 
man  seizes  on  the  woman  whom  he  wishes  for  his  wife  by 
actual  or  pretended  force;  but  '^  on  reaching  the  home  of 
her  abductor,  should  she  not  approve  of  the  match,  she 
runs  to  some  one  who  can  protect  her;  if,  however,  she  is 
satisfied,  the  matter  is  settled  forthwith. '^  With  the  Kal- 
mucks there  is  a  regular  race  between  the  bride  and  bride- 
groom, the  former  having  a  fair  start;  and  Clarke  '*  was 
assured  that  no  instance  occurs  of  a  girl  being  caught, 
unless  she  has  a  partiality  to  the  pursuer."  Among  the 
wild  tribes  of  the  Malay  Archipelago  there  is  also  a  racing 
match;  and  it  appears  from  M.  Bourien's  account,  as  Sir 
J.  Lubbock  remarks,  that  *^the  race  ^is  not  to  the  swift, 
nor  the  battle  to  the  strong,'  but  to  the  young  man  who 
has  the  good  fortune  to  please  his  intended  bride."  A  sim- 
ilar custom,  with  the  same  result,  prevails  with  the  Korarks 
of  Northeastern  Asia. 

Turning  to  Africa — the  Kafirs  buy  their  wives,  and  girls 
are  severely  beaten  by  their  fathers  if  they  will  not  accept 
a  chosen  husband;  but  it  is  manifest  from  many  facts  given 
by  the  Rev.  Mr.  Shooter,  that  they  have  considerable 
power  of  choice.  Thus,  very  ugly,  though  rich  men,  have 
been  known  to  fail  in  getting  wives.  The  girls,  before  con- 
senting to  be  betrothed,  compel  the  men  to  show  them- 
selves off  first  in  front  and  then  behind,  and  ^'  exhibit  their 
paces."  They  have  been  known  to  propose  to  a  man,  and 
they  not  rarely  run  away  with  a  favored  lover.  So,  again, 
Mr.  Leslie,  who  was  intimately  acquainted  with  the  Kafirs, 


684  THE  DESCENT  OF  MAN. 

says:  "  It  is  a  mistake  to  imagine  that  a  girl  is  sold  by  her 
father  in  the  same  manner,  and  with  the  same  authority, 
with  which  he  would  dispose  of  a  cow.''  Among  the 
degraded  Bushmen  of  S.  Africa,  *^when  a  girl  has  grown 
up  to  womanhood  without  having  been  betrothed,  which, 
however,  does  not  often  happen,  her  lover  must  gain  her 
approbation  as  well  as  that  of  the  parents/'*  Mr.  Winwood 
Reade  made  inquiries  for  me  with  respect  to  the  negroes  of 
Western  Africa,  and  he  informs  me  that  'Hhe  women,  at 
least  among  the  more  intelligent  Pagan  tribes,  have  no  dif- 
ficulty in  getting  the  husbands  whom  they  may  desire, 
although  it  is  considered  unwomanly  to  ask  a  man  to  marry 
them.  They  are  quite  capable  of  falling  in  love  and  of 
forming  tender,  passionate  and  faithful  attachments." 
Additional  cases  could  be  given. 

We  thus  see  that  with  savages  the  women  are  not  in 
quite  so  abject  a  state  in  relation  to  marriage  as  has  often 
been  supposed.  They  can  tempt  the  men  whom  they 
prefer,  and  can  sometimes  reject  those  whom  they  dislike, 
either  before  or  after  marriage.  Preference  on  the  part  of 
women,  steadily  acting  in  any  one  direction,  would  ulti- 
mately affect  the  character  of  the  tribe;  for  the  women 
would  generally  choose  not  merely  the  handsomest  men, 
according  to  their  standard  of  taste,  but  those  who  were  at 
the  same  time  best  able  to  defend  and  support  them.  Such 
well-endowed  pairs  would  commonly  rear  a  larger  number 
of  oft'spring  than  the  less  favored.  The  same  result  would 
obviously  follow  in  a  still  more  marked  manner  if  there 
was  selection  on  both  sides;  that  is,  if  the  more  attractive, 
and,  at  the  same  time,  more  powerful,  men  were  to  prefer, 
and  were  preferred  by,  the  more  attractive  women.  And 
this   double   form   of    selection    seems    actually   to   have 

*  Azara  "  Voyages, "  etc.,  torn,  ii,  p.  23.  Dobrizboffer,  "An  Ac- 
count of  tbe  Abipones,"  vol.  ii,  1822,  p.  207.  Capt.  Musters,  in 
"  Proc.  R.  Geograpb.  Soc,"  vol.  xv,  p.  47.  Williams  on  tbe  Fiji 
Islanders,  as  quoted  by  Lubbock,  "Origin  of  Civilization,"  1870.  p. 
79.  On  tbe  Fuegians,  King  and  Fitzroy,  "  Voyages  of  tbe  'Advent- 
ure' and  '  Beagle,*  "  vol.  ii,  1839,  p.  182.  On  tbe  Kalmucks,  quoted  by 
M'Lennan,  "  Primitive  Marriage,"  1865,  p.  32.  On  tbe  Malays,  Lub- 
bock, ibid,  p.  76.  Tbe  Kev.  J.  Sbooter,  "On  tbe  Kafirs  of  Natal," 
1857,  pp.  52-60.  Mr.  D.  I^eslie,  "Kafir  Cbaracter  and  Customs," 
1871,  p.  4.  On  tbe  Busbmen,  Burcbell,  "Travels  in  S.  Africa,"  vol. 
ii,  1824,  p.  59.  On  tbe  Koraks  by  McKennan,  as  quoted  by  Mr. 
Wake,  in  "  Antbropologia,"  Oct.,  1873,  p.  75. 


SECONDARY  SEXUAL  CHARACTERS.  685 

occurred,  especially  during  the  earlier  periods  of  our  long 
history. 

We  will  now  examine  a  little  more  closely  some  of  the 
characters  which  distinguish  the  several  races  of  man  from 
one  another  and  from  the  lower  animals,  namely,  the 
greater  or  less  deficiency  of  hair  on  the  body  and  the  color 
of  the  skin.  We  need  say  nothing  about  the  great  diversity 
in  the  shape  of  the  features  and  of  the  skull  between  the 
different  races,  as  we  have  seen  in  the  last  chapter  how  dif- 
ferent is  the  standard  of  beauty  in  these  respects.  These 
characters  will,  therefore,  probably  have  been  acted  on 
through  sexual  selection;  but  we  have  no  means  of  judging 
whether  they  have  been  acted  on  chiefly  from  the  male  or 
female  side.  The  musical  faculties  of  man  have  likewise 
been  already  discussed. 

Absence  of  Hair  on  the  Body  and  Its  Development  on 
the  Face  and  Head. — From  the  presence  of  the  woolly  hair 
or  lanugo  on  the  human  fetus,  and  of  rudimentary  hairs 
scattered  over  the  body  during  maturity,  we  may  infer  that 
man  is  descended  from  some  animal  Avhich  was  born  hairy 
and  remained  so  during  life.  The  loss  of  hair  is  an  incon- 
venience and  probably  an  injury  to  man,  even  in  a  hot 
climate,  for  he  is  thus  exposed  to  the  scorching  of  the  sun, 
and  to  sudden  chills,  especially  during  wet  weather.  As 
Mr.  Wallace  remarks,  the  natives  in  all  countries  are  glad 
to  protect  their  naked  backs  and  shoulders  with  some 
slight  covering.  No  one  supposes  that  the  nakedness  of 
the  skin  is  any  direct  advantage  to  man;  his  body,  there- 
fore, cannot  have  been  divested  of  hair  tlirough  natural 
selection.*  Nor,  as  shown  in  a  former  chapter,  have  we 
any  evidence  that  this  can  be  due  to  the  direct  action  of 
climate,  or  that  it  is  the  result  of  correlated  development. 

The  absence  of  hair  on  the  body  is  to  a  certain  extent  a 

♦"Contributions  to  the  Theory  of  Natural  Selection,"  1870,  p. 
346.  Mr,  Wallace  believes  (p.  350)  "that  some  intelligent  power 
has  guided  or  determined  the  development  of  n)an  ;"  and  he  con- 
siders the  hairless  condition  of  the  skin  as  coming  under  this 
head.  The  Rev.  T.  R.  Stebbing,  in  commenting  on  this  view 
("Transactions  of  Devonshire  Assoc,  for  Science,"  1870)  remarks, 
that  had  Mr.  Wallace  "employed  his  usual  ingenuity  on  the  queS' 
tion  of  man's  hairless  skin  he  might  have  seen  the  possibility  of  its 
selection  through  its  superior  beauty  or  the  health  attaching  to 
superior  cleanliness." 


THE  DESCENT  OF  MAN. 

secondary  sexual  character;  for  in  all  parts  of  the  world 
women  are  less  hairy  than  the  men.  Tlierefore  we  may 
l*easonably  suspect  that  this  character  has  been  gained 
through  sexual  selection.  We  know  that  the  faces  of 
several  species  of  monkeys,  and  large  surfaces  at  the 
posterior  end  of  the  body  of  other  species,  have  been 
denuded  of  hair;  and  this  we  may  safely  attribute  to 
sexual  selection,  for  these  surfaces  are  not  only  vividly 
colored,  but  sometimes,  as  with  the  male  mandrill  and 
female  rhesus,  much  more  vividly  in  the  one  sex  than  in 
the  other,  especially  during  the  breeding-season.  I  am 
informed  by  Mr.  Bartlett  that,  as  these  animals  gradually 
reach  maturity,  the  naked  surfaces  grow  larger  compared 
with  the  size  of  their  bodies.  The  hair,  however,  appears 
to  have  been  removed,  not  for  the  sake  of  nudity,  but  that 
the  color  of  the  skin  may  be  more  fully  displayed.  So, 
again,  with  many  birds,  it  appears  as  if  the  head  and  neck 
had  been  divested  of  feathers,  through  sexual  selection,  to 
exhibit  the  brightly  colored  skin. 

As  the  body  in  woman  is  less  hairy  than  in  man,  and  as 
this  character  is  common  to  all  races,  we  may  conclude 
that  it  was  our  female  semi- human  ancestors  who  were  first 
divested  of  ha'r,  and  that  this  occurred  at  an  extremely  re- 
mote period  before  the  several  races  had  diverged  from  a 
common  stock.  While  our  female  ancestors  were  gradually 
acquiring  this  new  character  of  nudity  they  must  have 
transmitted  it  almost  equally  to  their  offspring  of  both 
sexes  while  young;  so  that  its  transmission,  as  with  the 
ornaments  of  many  mammals  and  birds,  has  not  been 
limited  either  by  sex  or  age.  There  is  nothing  surprising 
in  a  partial  loss  of  hair  having  been  esteemed  as  an  orna- 
ment by  our  ape-like  progenitors,  for  we  have  seen  that  in- 
numerable strange  characters  have  been  thus  esteemed  by 
animals  of  all  kinds  and  have  consequently  been  gained 
through  sexual  selection.  Nor  is  it  surprising  that  a 
slightly  injurious  character  should  have  been  thus  acquired; 
for  we  know  that  this  is  the  case  with  the  plumes  of  certain 
birds,  and  with  the  horns  of  certain  stags. 

The  females  of  some  of  the  anthropoid  apes,  as  stated  in 
a  former  chapter,  are  somewhat  less  hairy  on  the  under 
surface  than  the  males;  and  here  we  have  what  might  have 
afforded  a  commencement  for  the  process  of  denudation. 
With  respect  to  the  completion  of  the  process  through 


SECONDARY  SEXUAL  CHARACTERS.  687 

sexual  selection,  it  is  well  to  bear  in  mind  the  New  Zea- 
land proverb:  "  There  is  no  woman  for  a  hairy  man."  All 
who  have  seen  photographs  of  the  Siamese  hairy  family 
will  admit  how  ludicrously  hideous  is  the  opposite  extreme 
of  excessive  hairiness.  And  the  king  of  Siam  had  to  bribe 
a  man  to  marry  the  first  hairy  woman  in  the  family;  and 
she  transmitted  this  character  to  her  young  offspring  of 
both  sexes.* 

Some  races  are  much  more  hairy  than  others,  especially 
the  males;  but  it  must  not  be  assumed  that  the  more  hairy 
races,  such  as  the  Europeans,  have  retained  tlieir  j^rimor- 
dial  condition  more  completely  than  the  naked  races,  such 
as  the  Kalmucks  or  Americans.  It  is  more  probable  that 
the  iiairiness  of  the  former  is  due  to  partial  reversion;  for 
characters  which  have  been  at  some  it>rmer  period  long  in- 
herited are  always  apt  to  return.  We  have  seen  that  idiots 
are  often  very  hairy,  and  they  are  apt  to  revert  in  other 
character  to  a  lower  animal  type.  It  does  not  a])pear  that 
a  cold  climate  has  been  influential  in  leading  to  this  kind 
of  reversion;  excepting  perhaps  with  the  negroes,  w^ho  have 
been  reared  during  several  generations  in  the  United 
States,  f  and  possibly  with  the  Ainos,  who  inhabit  the 
northern  islands  of  the  Japan  archipelago.  But  the  laws 
of  inheritance  are  so  complex  that  we  can  seldom  under- 
stand their  action.  If  the  greater  hairiness  of  certain 
races  be  the  result  of  reversion,  unchecked  by  any  form  of 
selection,  its  extreme  variability,  even  within  the  limits  of 
the  same  race,  ceases  to  be  remarkable.  J 

*  "  The  Variation  of  Animals  and  Plants  under  Domestication," 
vol.  ii,  1868,  p.  327. 

f  "  Investigations  into  Military  and  Anthropological  Statistics  of 
American  Soldiers,"  by  B.  A.  Gould,  1869;  p.  568: — Observations 
were  carefully  made  on  tlie  hairiness  of  2,129  black  and  colored 
soldiers,  while  they  were  bathing;  and  by  looking  to  the  published 
table,  "it  is  manifest  at  a  glance  that  there  is  but  little,  if  any,  dif- 
ference between  the  white  and  the  black  races  in  this  respect."  It  is, 
however,  certain  that  negroes  in  their  native  and  much  hotter  land 
of  Africa,  have  remarkably  smooth  bodies.  It  should  be  particularly 
observed,  that  both  pure'  blacks  and  mulattoes  were  included  in 
the  above  enumeration;  and  this  is  an  unfortunate  circumstance,  as 
in  accordance  with  a  principle,  the  truth  of  which  I  have  elsewhere 
proved,  crossed  races  of  man  would  be  eminently  liable  to  revert  to 
the  primordial  hairy  character  of  their  early  ape-like  progenitors. 

X  Hardly  any  view  advanced  in  this  work  has  met  with  so  much 
disfavor  (see  for  mstftnce,  Spengel,  ♦'  Die  Forte^Uritte  des  Darwiu- 


688  THE  DESCENT  OF  MAN. 

With  respect  to  the  heard  in  man,  if  we  turn  to  our  hest 
guide,  the  Quadrumana,  we  find  beards  equally  developed 
in  both  sexes  of  many  s^^ecies,  but  in  some,  either  confined 
to  the  males,  or  more  developed  in  them  than  in  the  females. 
From  this  fact  and  from  the  curious  arrangement,  as  well 
as  the  bright  colors  of  the  hair  about  the  heads  of  many 
monkeys,  it  is  highly  probable,  as  before  explained,  that 
the  males  first  acquired  tlieir  beards  through  sexual  selec- 
tion as  an  ornament,  transmitting  them  in  most  cases, 
equally  or  nearly  so,  to  their  offspring  of  both  sexes.  We 
know  from  Eschricht*  that  with  mankind  the  female  as 
well  as  the  male  fetus  is  furnished  with  much  hair  on  the 
face,  especially  round  the  mouth;  and  this  indicates  that 
we  are  descended  from  progenitors  of  whom  both  sexes 
were  bearded.  It  appears,  therefore,  at  first  sight  probable 
that  man  has  retained  his  beard  from  a  very  early  period, 
while  woman  lost  her  beard  at  the  same  time  that  her  body 
became  almost  completely  divested  of  hair.  Even  the  color 
of  our  beards  seems  to  have  been  inherited  from  an  ape- 
like progenitor;  for  when  there  is  any  difference  in  tint 
between  the  hair  of  the  head  and  the  beard,  the  latter  is 
lighter  colored  in  all  monkeys  and  in  man.  In  those 
Quadrumana  in  which  the  male  lias  a  larger  beard  than 
that  of  the  female,  it  is  fully  developed  only  at  maturity. 
Just  as  with  mankind;  and  it  is  possible  that  only  the  latei 
stages  of  development  have  been  retained  by  man.  In  op- 
position to  this  view  of  the  retention  of  the  beard  from  an 
early  period  is  the  fact  of  its  great  variability  in  different 
races,  and  even  within  the  same  race;  for  this  indicates 
reversion — long  lost  characters  being  very  apt  to  vary  on 
reappearance. 

Nor  must  we  overlook  the  part  which  sexual  selection 
may  have  played  in  later  times;  for  we  know  that  with 
savages  the  men  of  the  beardless  races  take  infinite  pains 
in  eradicating  every  hair  from  their  faces  as  something 
odious,  while  the  men  of  the  bearded  races  feel  the  greatest 

israus,"  1874,  p.  80)  as  the  above  explanation  of  the  loss  of  hair  in 
mankind  through  sexual  selection;  but  none  of  the  opposed  argu- 
ments seem  to  me  of  much  weight,  in  comparison  with  the  facts 
showing  that  the  nudity  of  the  skin  is  to  a  certain  extent  a  secon- 
dary sexual  character  in  man  and  in  some  of  the  Quadrumana. 

*  "  Ueber  die  Richtung  der  Haare  am  Menschlichen  K6rper,"  in 
MtUler's  "  ArcUiv  fiir  Anat.  und  Phys.,"  1837,  s.  40. 


SECONDARY  SEXUAL  CHARACTERS.  689 

pride  in  their  beards.  The  women,  no  doubt,  participate 
in  these  feelings,  and  if  so  sexual  selection  can  hardly  have 
failed  to  have  effected  something  in  the  course  of  later 
times.  It  is  also  possible  that  the  long-continued  habit  of 
eradicating  the  hair  may  have  produced  an  inherited  effect. 
Dr.  Brown-Sequard  has  shown  that  if  certain  animals  are 
operated  on  in  a  particular  manner  their  offspring  are 
affected.  Further  evidence  could  be  given  of  the  inherit- 
ance of  the  effects  of  mutilations;  but  a  fact  lately  ascer- 
by  Mr.  Salvin  *  has  a  more  direct  bearing  on  the  present 
question;  for  he  has  shown  that  the  motmots,  which  are 
known  habitually  to  bite  off  the  barbs  of  the  two  central 
tail-feathers,  have  the  barbs  of  these  feathers  naturally 
somewhat  reduced,  f  Nevertlieless,  with  mankind  the 
habit  of  eradicating  the  beard  and  the  hairs  on  the  body 
would  probably  not  have  arisen  until  these  had  already 
become  by  some  means  reduced. 

It  is  difficult  to  form  any  judgment  as  to  how  the  hair 
on  the  head  became  developed  to  its  present  great  length 
in  many  races.  EschrichtJ;  states  that  in  the  human  fetus 
the  hair  on  the  face  during  the  fifth  month  is  longer  than 
that  on  the  head;  and  this  indicates  that  our  semi-human 
progenitors  were  not  furnished  with  long  tresses,  which 
must,  therefore,  have  been  a  late  acquisition.  This  is  like- 
wise indicated  by  the  extraordinary  difference  in  the  length 
of  the  hair  in  the  different  races;  in  the  negro  the  hair 
forms  a  mere  curly  mat;  with  us  it  is  of  great  length,  and 
with  the  American  natives  it  not  rarely  reaches  to  the 
ground.  Some  species  of  Semnopithecus  have  their  heads 
covered  with  moderately  long  hair,  and  this  probably  serves 
as  an  ornament  and  was  acquired  through  sexual  selection. 
The  same  view  may,  perhaps,  be  extended  to  mankind,  for 
we  know  that  long  tresses  are  now  and  were  formerly  much 
admired,  as  may  be  observed  in  the  works  of  almost  every 
poet.     St.  Paul  says:  *'If  a  woman  have  long  hair  it  is  a 

*  On  the  tail-feathers  of  Momotus,  "  Proc.  Zooloer.  Soc.,"  1873,  p. 
429. 

f  Mr.  Sproat  has  suggested  ("  Scenes  and  Studies  of  Savage  Life," 
1868,  p.  25)  this  same  view.  Some  distinguished  ethnologists,  among 
others  M.  Gosse  of  Geneva,  believe  that  artificial  modifications  of  the 
skull  tend  to  be  inherited. 

\  "  Uber  die  Bichtung,"  ibid,  s.  40. 


690  ^'^E  DESCmr  OF  MAN. 

glory  to  her;''  and  we  have  seen  that  in  North  America  a 
chief  was  elected  solely  from  the  length  of  his  hair. 

Color  of  the  Skin. — The  best  kind  of  evidence  that  in 
man  the  color  of  the  skin  has  been  modified  through  sexual 
selection  is  scanty;  for  in  most  races  the  sexes  do  not  differ 
in  this  respect,  and  only  slightly,  as  we  have  seen,  in 
others.  We  know,  however,  from  the  many  facts  already 
given  that  the  color  of  the  skin  is  regarded  by  the  men  of 
all  races  as  a  highly  important  element  in  their  beauty;  so 
that  it  is  a  character  which  would  be  likely  to  have  been 
modified  through  selection,  as  has  occurred  in  innumerable 
instances  with  the  lower  animals.  It  seems  at  first  sight  a 
monstrous  supposition  that  the  jet  blackness  of  the  negro 
should  have  been  gained  through  sexual  selection;  but 
this  view  is  supported  by  various  analogies,  and  we  know 
that  negroes  admire  their  own  color.  With  mammals 
when  the  sexes  differ  in  color  the  male  is  often  black  or 
much  darker  than  the  female;  and  it  depends  merely  on 
the  form  of  inheritance  whether  this  or  any  other  tint  is 
transmitted  to  both  sexes  or  to  one  alone.  The  resemblance 
to  a  negro  in  miniature  of  Pitliecia  satanas  with  his 
jet-black  skin,  white  rolling  eyeballs  and  hair  parted  on 
tho  top  of  the  head  is  almost  ludicrous. 

The  color  of  the  face  differs  much  more  widely  in  the 
various  kinds  of  monkeys  than  it  does  in  the  races  of  man; 
and  we  have  some  reason  to  believe  that  the  red,  blue, 
orange,  almost  white  and  black  tints  of  their  skin,  even 
when  common  to  both  sexes,  as  well  as  the  bright  colors  of 
their  fur  and  the  ornamental  tufts  about  the  head,  have 
all  been  acquired  through  sexual  selection.  As  the  order 
of  development  during  growth  generally  indicates  the  order 
in  which  the  characters  of  a  species  have  been  developed 
and  modified  during  previous  generations,  and  as  the 
newly  born  infants  of  the  various  races  of  man  do  not  differ 
nearly  as  much  in  color  as  do  the  adults,  although  their 
bodies  are  as  completely  destitute  of  hair,  we  have  some 
slight  evidence  that  the  tints  of  the  different  races  were 
acquired  at  a  period  subsequent  to  the  removal  of  the  hair, 
which  must  have  occurred  at  a  very  early  period  in  the 
history  of  man. 

Summary. — We  may  conclude   that  the  greater  size, 


SECONDARY  SEXUAL  CHARACTERS.  691 

strength,  courage,  pugnacity,  and  energy  of  man,  in  com- 
parison with  women,  were  acquired  during  primeval  times, 
and  have  subsequently  been  augmented,  chiefly  through 
the  contests  of  rival  males  for  the  possession  of  the  females. 
The  greater  intellectual  vigor  and  power  of  invention  in 
man  is  probably  due  to  natural  selection,  combined  with 
the  inherited  effects  of  habit,  for  the  most  able  men  will 
have  succeeded  best  in  defending  and  providing  for  them- 
selves and  for  their  wives  and  offspring.  As  far  as  the  ex- 
treme intricacy  of  the  subject  permits  us  to  judge,  it 
appears  that  our  male  ape-like  progenitors  acquired  their 
beards  as  an  ornament  to  charm  or  excite  the  opposite  sex, 
and  transmitted  them  only  to  their  male  offspring.  The 
females  apparently  first  had  their  bodies  denuded  of  hair, 
also  as  a  sexual  ornament;  but  they  transmitted  this  char- 
acter almost  equally  to  both  sexes.  It  is  not  improbable 
that  the  females  were  modified  in  other  respects  for  the 
same  purpose  and  by  the  same  means;  so  that  women  have 
acquired  sweeter  voices  and  become  more  beautiful  than 
men. 

It  deserves  attention  that  with  mankind  the  conditions 
were  in  many  respects  much  more  favorable  for  sexual 
selection,  during  a  very  early  period,  when  man  had  only 
just  attained  to  the  rank  of  manhood,  than  during  later 
times.  For  he  would  then,  as  we  may  safely  conclude, 
have  been  guided  more  by  his  instinctive  passions,  and 
less  by  foresight  or  reason.  He  would  have  jealousy 
guarded  his  wife  or  wives.  He  would  have  practiced 
infanticide;  nor  valued  his  wives  merely  as  useful  slaves; 
nor  have  been  betrothed  to  them  during  infancy.  Hence 
we  may  infer  that  the  races  of  men  were  differentiated,  as 
far  as  sexual  selection  is  concerned,  in  chief  part  at  a  very 
remote  epoch ;  and  this  conclusion  throws  light  on  the 
remarkable  fact  that  at  the  most  ancient  period,  of  which 
we  have  as  yet  any  record,  the  races  of  man  had  already 
come  to  differ  nearly  or  quite  as  much  as  they  do  at  the 
present  day. 

The  views  here  advanced,  on  the  part  which  sexual  selec- 
tion has  played  in  the  history  of  man,  want  scientific  pre- 
cision. He  who  does  not  admit  this  agency  in  the  case  of 
the  lower  animals,  will  disregard  all  that  I  have  written  in 
the  later  chapters  on  man.  We  cannot  positively  say  that 
this  character,  but  not  that,  has  been  thus  modified;  it  hae. 


692  THE  DESCENT  OF  MAN. 

however,  been  shown  that  the  races  of  man  differ  fiom 
each  other  and  from  their  nearest  allies,  in  certain  charac- 
ters which  are  of  no  service  to  them  in  their  daily  habits 
of  life,  and  which  it  is  extremely  probable  would  have 
been  modified  tlirough  sexual  selection.  We  have  seen  that 
with  the  lowest  savages  the  people  of  each  tribe  admire  their 
own  characteristic  qualities — the  shape  of  the  head  and 
face,  the  squareness  of  tlie  cheek-bones,  the  prominence  or 
depression  of  the  nose,  the  color  of  the  skin,  the  length  of 
the  hair  on  the  head,  the  absence  of  hair  on  the  face  and 
body,  or  the  presence  of  a  great  beard,  and  so  forth.  Hence 
these  and  other  such  points  could  hardly  fail  to  be  slowly 
and  gradually  exaggerated  from  the  more  powerful  and  able 
men  in  each  tribe,  who  would  succeed  in  rearing  the  largest 
number  of  offspring,  having  selected  during  many  genera- 
tions for  their  wives  the  most  strongly  characterized  and 
therefore  most  attractive  women.  For  my  own  part  I  con- 
clude that  of  all  the  causes  which  have  led  to  the  differ- 
ences in  external  appearance  between  the  races  of  man,  and 
to  a  certain  extent  between  man  and  the  lower  animals, 
sexual  selection  has  been  the  most  efficient. 


GENERAL  SUMMARY  AND  CONCLUSION.         693 


CHAFIER    XXI. 

OEXERAL  SUMMARY  AlfD  CONCLUSIOK. 

Main  conclosion  that  man  is  descended  from  some  lower  form — 
Manner  of  development — Genealogy  of  man — Intellectual  and 
moral  faculties — Sexual  selection-^'oncluding  remarks. 

A  BRIEF  summary  will  be  sufficient  to  recall  to  the 
reader^s  mind  the  more  salient  points  in  this  work.  Many 
of  the  views  which  have  been  advanced  are  highly  specula- 
tive, and  some  no  doubt  will  prove  erroneous;  but  I  have 
in  every  case  given  the  reasons  which  have  led  me  to  one 
view  rather  than  to  another.  It  seemed  worth  while  to  try 
how  far  the  principle  of  evolution  would  throw  light  on 
some  of  the  more  complex  problems  in  the  natural  history 
of  man.  False  facts  are  highly  injurious  to  the  progress 
of  science,  for  they  often  endure  long;  but  false  views,  if 
supported  by  some  evidence,  do  little  harm,  for  every  one 
takes  a  salutary  pleasure  in  proving  their  falseness;  and, 
when  this  is  done,  one  path  toward  error  is  closed  and  the 
road  to  truth  is  often  at  the  same  time  opened. 

The  main  conclusion  here  arrived  at,  and  now  held  by 
many  naturalists,  who  are  well  competent  to  form  a  sound 
judgment,  is  that  man  is  descended  from  some  less  highly 
organized  form.  The  grounds  upon  which  this  conclusion 
rests  will  never  be  shaken,  for  the  close  similarity  between 
man  and  the  lower  animals  in  embryonic  development, 
as  well  as  in  innumerable  points  of  structure  and  constitu- 
tion, both  of  high  and  of  the  most  trifling  iriiportance — the 
rudiments  which  he  retains,  and  the  abnormal  reversions  to 
which  he  is  occasionally  liable — are  facts  which  cannot  be 
disputed.  They  have  long  been  known,  but,  until  recently, 
they  told  us  nothing  with  respect  to  the  origin  of  man. 
Now,  when  viewed  by  the  light  of  our  knowledge  of  the 
whole  organic  world,  their  meaning  is  unmistakable.  The 
great  principle  of  evolution  stands  up  clear  and  firm  when 
these  groups  of  facts  are  considered  in  connection  with 


oftiw 

It  Is  incredi- 
lilnrly.   He  vho  is  noi 

He  win  be  ioned  to 

of  tiieonhrfoof  ma  to 

eoHlnietion'of  hkekiill, 

OB  tihe  OHM  pimn  with  that  of  othor 

~    <rf  ^le  on  to  whidi  Uie  ptfts 

be   p^ — tke    nrrwinnil    leappeemiee   <tf   Tarious 

of  Kienl  maadeB,  which  maa 

%  bat  wbidi  are  eomaioa  to  the 

wd  of  aaalogoaa  £m:Ib — all  point 

'  to  tte  eondanoa  iSbaX  aiaa  ie 

I  oilier  iHBMiiwIii  of  a  eoauaon 

ia  afl  parta  of  bis  body  «id  in  his  mental 
Tbcae  differeaeeB  cm*  Tariatians  seem  to  be 
ladaeed  \n  tiie  Baaie  geaoal  caaan,  and  to  obe j  the  nine 
w^  flbe  lover  aatmalw  la  both  cases  eimihu'  laws 
iaheri^aoe  piefafl.  Maa  teads  to  increase  at  a  greater 
of  sabastenee:  consequently  he  is  occa- 
to  a  aerere  etrnggle  for  existence,  and 
win  bare  eHected  whatcTer  lies  within  its 
A  aaeeeamm  of  strongly  marked  Tariations  of  a 
aataie  is  br  no  means  requisite:  slight  flnctaating 
ia  the  indiTidnal  saffice  for  the  work  of  natural 
aeleelioB;  aoi  Uiai  we  have  aaj  reason  to  suppose  that  in 
Uie  awae  ^ecics  afl  parts  of  tins  organization  tend  to  vary 
to  the  asaie  degree.  VTe  maj  feel  assared  that  the  inherited 
eSeeti  of  the  kyng-continued  use  or  disuse  of  parts  will 
bare  doae  much  in  the  same  direction  with  natural  selec- 
tioB.  Modifications  formerly  of  importance,  though  no 
kmga'of  any  special  use.  are  long-inheriteri.  Wbea~one 
part  in  modified  other  parts  change  through  the  principle 
of  corrdatioB,  of  which  we  hare  instances  in  many  curious 
eases  of  correlated  monstooaties.  Something  may  be 
attribated  to  the  direct  and  definite  action  of  the  surround- 
iag  eoaditioos  of  life^  such  as  abundant  food,  heat  or 
moutare;  and^  hurtly,  many  characters  of   slight  physio- 


GENERAL  3  UMMAR  Y  AND  CONCL  U8I0N.         695 

logical  importance,  acme  indeed  of  considerable  ImportaEnee, 
have  been  gained  through  sexnal  selection. 

No  doubt  man,  ae  well  as  erery  other  animal,  presentB 
structures,  which  seem  to  our  limited  knowledge,  not  to  be 
now  of  any  service  to  him.  nor  to  have  been  so  formerly, 
either  for  the  general  conditions  of  life,  or  in  the  relations 
of  one  sex  to  the  other.  Such  structures  cannot  be 
accounted  for  by  any  form  of  selection,  or  by  the  inherited 
effects  of  the  use  and  disuse  of  parts.  We  know,  however, 
that  many  strange  and  strongly  marked  peculiarities  of 
stmctiire  occasionally  appear  in  our  domesticated  produc- 
tions, and  if  their  unknown  causes  were  to  act  more  uni- 
formly, they  would  probably  become  common  to  all  the 
individuals  of  the  species.  We  may  hope  hereafter  to 
undergtand  something  about  the  causes  of  such  occasional 
modifications,  eqiccially  through  the  study  of  monstroeities: 
hence,  the  Idbon  of  experimentalists,  such  as  those  of  M. 
Camille  Dareste,  are  full  of  promae  for  the  future.  In 
general  we  can  only  say  that  the  €amm  of  each  slight  varia- 
tion and  of  each  waaasLnmkf  iieB  nuch  more  in  the  con- 
stitution of  the  orginlw  thm  in  the  nature  of  the  sur- 
rounding conditions;  tluNi^  arw  and  changed  conditions 
certainly  play  an  impor£iat  part  in  exciting  organic 
changes  of  many  kinds. 

Through  the  mesne  jost  specified,  aided  perhaps  by 
others  as  yet  unditoofeicd,  bjui  has  been  raised  to  his 
present  state.  But  since  he  attained  to  the  rank  of  man- 
hood, he  has  diverged  into  distinct  laces.  or.  as  they  may 
be  more  fitly  caUed,  sob-species.  Some  of  these,  such  as 
the  negro  and  Enropcttn,  are  so  distinct  that,  if  specimens 
had  been  brought  to  a  naturalist  without  any  further  in- 
formation, they  would  undoubtedly  have  been  considered 
by  him  as  good  and  true  species.  Nevertheless,  all  the 
races  agree  in  so  many  unimportant  details  of  structure  and 
in  so  many  mental  peculiarities  that  these  can  be  ac- 
counted for  only  by  inheritance  from  a  common  progenitor; 
and  a  progenitor  thus  characterized  would  probably  deserve 
to  rank  its  man. 

It  must  not  be  supposed  that  the  divergence  of  each  race 
* 'om  the  other  races  and  of  all  from  a  common  stock  can 
traced  back  to  any  one  pair  of  progenitors.  On  the  con- 
trary, at  every  stage  in  the  process  of  modification,  all  the 
individuals  which  were  in  any  way  better  fitted  for  their 


696  ^^^  bSSCMT  OP  MAl^. 

conditions  of  life,  though  in  different  degrees,  would  have 
survived  in  greater  numbers  than  the  less  well-fitted.  The 
process  would  have  been  like  that  followed  by  man,  when 
he  does  not  intentionally  select  particular  individuals,  but 
breeds  from  all  the  superior  individuals  and  neglects  the 
inferior.  He  thus  slowly  but  surely  modifies  his  stock  and 
unconsciously  forms  a  new  strain.  So  with  respect  to 
modifications  acquired  independently  of  selection,  and  due 
to  variations  arising  from  the  nature  of  the  organism  and 
the  action  of  the  surrounding  conditions,  or  from  changed 
habits  of  life,  no  single  pair  will  have  been  modified  much 
more  than  the  other  pairs  inhabiting  the  same  country,  for 
all  will  have  been  continually  blended  through  free  inter- 
crossing. 

By  considering  the  embryological  structure  of  man — the 
homologies  which  he  presents  with  the  lower  animals — the 
rudiments  which  he  retains — and  the  reversions  to  which 
he  is  liable,  we  can  partly  recall  in  imagination  the  former 
condition  of  our  early  progenitors;  and  can  approximately 
place  them  in  their  proper  place  in  the  zoological  series. 
We  thus  learn  that  man  is  descended  from  a  hairy,  tailed 
quadruped,  probably  arboreal  in  its  habits  and  an  inhabi- 
tant of  the  Old  World.  This  creature,  if  its  whole 
structure  had  been  examined  by  a  naturalist,  would  have 
been  classed  among  the  Quadrumana,  as  surely  as  the  still 
more  ancient  progenitor  of  the  Old  and  New  World  mon- 
keys. The  Quadrumana  and  all  the  higher  mammals  are 
probably  derived  from  an  ancient  marsupial  animal  and 
this  through  a  long  line  of  diversified  forms,  from  some 
amphibian-like  creature,  and  this  again  from  some  fish-like 
animal.  In  the  dim  obscurity  of  the  past  we  can  see  that 
the  early  progenitor  of  all  the  Vertebrata  must  have  been  an 
aquatic  animal,  provided  with  branchiae,  with  the  two  sexes 
united  in  the  same  individual,  and  with  the  most  important 
organs  of  the  body  (such  as  the  brain  and  heart)  imper- 
fectly or  not  at  all  developed.  This  animal  seems  to  have 
been  more  like  the  larvae  of  the  existing  marine  Ascidians 
than  any  other  known  form. 

The  high  standard  of  our  intellectual  powers  and  moral  dis- 
position is  the  greatest  difficulty  whicli  presents  itself,  after 
we  have  been  driven  to  this  conclusion  on  the  origin  of 
man.     But  every  one  who  admits  the  principle  of  evolution 


GENERAL  SUMMARY  AND  CONCLUSION.         697 

must  see  that  the  mental  powers  of  the  higher  animals, 
which  are  the  same  in  kind  with  those  of  man,  though  so 
different  in  degree,  are  capable  of  advancement.  Thus 
the  interval  between  the  mental  powers  of  one  of  the 
higher  apes  and  of  a  fish,  or  between  those  of  an  ant  and 
scale-insect,  is  immense ;  yet  their  development  does  not 
offer  any  special  difficulty  ;  for  with  our  domesticated 
animals  the  mental  faculties  are  certainly  variable,  and 
the  variations  are  inherited.  No  one  doubts  that  they  are 
of  the  utmost  importance  to  animals  in  a  state  of  nature. 
Therefore,  the  conditions  are  favorable  for  their  develop- 
ment through  natural  selection.  The  same  conclusion 
may  be  extended  to  man;  the  intellect  must  have  been  all- 
important  to  him,  even  at  a  very  remote  period,  as  enabling 
him  to  invent  and  use  language,  to  make  weapons,  tools, 
traps,  etc.,  whereby  with  tlie  aid  of  his  social  habits  he 
long  ago  became  the  most  dominant  of  all  living  creatures. 

A  great  stride  in  the  development  of  the  intellect  will 
have  followed,  as  soon  as  the  half -art  and  half -instinct 
of  language  came  into  use;  for  the  continued  use  of  lan- 
guage will  have  reacted  on  the  brain  and  produced  an 
inherited  effect;  and  this  again  will  have  reacted  on  the 
improvement  of  language.  As  Mr.  Ohauncey  Wright*  has 
well  remarked,  the  largeness  of  the  brain  in  man  relatively 
to  his  body,  compared  with  the  lower  animals,  may  be 
attributed  in  chief  part  to  the  early  use  of  some  simple 
form  of  language — that  wonderful  engine  which  affixes 
signs  to  all  sorts  of  objects  and  qualities,  and  excites  trains 
of  thought  which  would  never  arise  from  the  mere  impression 
of  the  senses,  or  if  they  did  arise  could  not  be  followed  out. 
The  higher  intellectual  powers  of  man,  such  as  those  of 
ratiocination,  abstraction,  self-consciousness,  etc.,  probably 
follow  from  the  continued  improvement  and  exercise  of  the 
other  mental  faculties. 

The  development  of  the  moral  qualities  is  a  more  inter- 
esting problem.  The  foundation  lies  in  the  social  instincts, 
including  under  this  term  the  family  ties.  These  instincts 
are  highly  complex,  and  in  the  case  of  the  lower  animals 
give  special  tendencies  toward  certain  definite  actions;  but 
the  more   important  elements  are  love   and   the   distinct 

*  "  On  the  Limits  of  Natural  Selecticfh,"  in  the  "  North  American 
Review,"  Oct.,  1870,  p.  295. 


698  THE  t)E8CENt  OF  MAI^. 

emotion  of  sympathy.  Animals  endowed  with  the  social 
instincts  take  pleasure  in  one  another's  company,  warn  one 
another  of  danger,  defend  and  aid  one  another  in  many 
ways.  These  instincts  do  not  extend  to  all  the  individuals 
of  the  species,  but  only  to  tliose  of  the  same  community. 
As  they  are  highly  beneficial  to  the  species  they  have  in  all 
probability  been  acquired  through  luitural  selection. 

A  moral  being  is  one  who  is  capable  of  reflecting  on  his 
past  actions  and  their  motives — of  approving  of  some  and 
disapproving  of  others;  and  the  fact  that  man  is  the  one 
being  who  certainly  deserves  this  designation  is  the  great- 
est of  all  distinctions  between  him  and  the  lower  animals. 
<But  in  the  fourth  chapter  I  have  endeavored  to  show  that 
the  moral  sense  follows,  firstly,  from  the  enduring  and  ever- 
present  nature  of  the  social  instincts;  secondly,  from  man's 
appreciation  of  the  approbation  and  disapprobation  of  his 
fellows;  and,  thirdly,  from  the  high  activity  of  his  mental 
laculties,  with  past  impressions  extremely  vivid;  and  in 
•these  latter  respects  he  differs  from  the  lower  animals. 
Owing  to  this  condition  of  mind,  man  cannot  avoid  look- 
ing both  backward  and  forward  and  comparing  past  im- 
pressions.    Hence  after  some  temporary  desire  or  passion 
ias  mastered  his  social  instincts,  he  reflects  and  compares 
Jlte  now  weakened  impression  of  such  pjist  impulses  with 
Jbhe  ever-present  social  instincts  ;  and  he  then  feels  that 
fcense  of  dissatisfaction  which  all  unsatisfied  instincts  leave 
/behind  them,  he  therefore  resolves  to  act  differently  for 
I  the  future — and  this  is4^nsc^ce.     Any  instinct  perma- 
I  nently  stronger  or  more  eiMurmg  than*  another  gives  rise 
Ho  a  feeling  which  we  express  by  saying  that  it  ought  to  be 
obeyed.     A  pointer  dog  if  able  to  reflect  on  his  past  con- 
duct would  say  to  himself,  I  ought  (as  indeed  we  say  of 
him)  to  have  pointed  at  that  hare  and  not  have  yielded  to 
the  passing  temptation  of  hunting  it. 

Social  animals  are  impelled  partly  by  a  wish  to  aid  the 
members  of  their  community  in  a  general  manner,  but 
more  commonly  to  perform  certain  definite  actions.  Man 
is  impelled  by  the  same  general  wish  to  aid  his  fellows; 
but  has  few  or  no  special  instincts.  He  differs  also  from 
the  lower  animals  in  the  power  of  expressing  his  desires  by 
words,  which  thus  become  a  guide  to  the  aid  required  and 
bestowed.  The  motive  to  give  aid  is  likewise  much  molli- 
fied in  man;  it  no  longer  consists  solely  of  a  blind  instinct- 


&BNERAL  SUMMARY  AND  CONCLUSlOlf,         699 

ite  impulse,  but  is  much  influenced  by  the  praise  or  blame 
of  his  fellows.  The  appreciation  and  the  bestowal  of 
praise  and  blame  both  rest  on  sympathy;  and  this  emotion, 
as  we  have  seen,  is  one  of  the  most  iniportant  elements  of 
the  social  instincts.  Sympathy,  though  gained  as  an  in- 
stinct, is  also  much  strengthened  by  exercise  or  habit.  As 
all  men  desire  their  o^vn  happiness,  praise  or  blame  is 
bestowed  on  actions  and  motives  according  as  they  lead  to 
this  end;  and  as  happiness  is  an  essential  part  of  the  gen- 
eral good  the  greatest-happiness  principle  indirectly  serves 
as  a  nearly  safe  standard  of  right  and  wrong.  As  the  rea- 
soning powers  advance  and  experience  is  gained  the  remoter 
effects  of  certain  lines  of  conduct  on  the  character  of  the 
individual  and  on  the  general  good  are  perceived;  and  then 
the  self -regarding  virtues  come  within  the  scope  of  public 
opinion  and  receive  praise  and  their  opposites  blame.  But 
with  the  less  civilized  nations  reason  often  errs,  and  many 
bad  customs  and  base  superstitions  come  within  the  same 
scope  and  are  then  esteemed  as  high  virtues  and  tlieir 
breach  as  heavy  crimes. 

The  moral  faculties  are  generally  and  justly  esteemed  as, 
of  higher  value  than  the  intellectual  powers.  But  we 
should  bear  in  mind  that  the  acti^'ity  of  the  mind  in  vividly 
recalling  past  impressions  is  one  of  the  fundamental  though 
secondary  bases  of  conscience.  This  affords  the  strongest 
argument  for  educating  and  stimulating  in  all  possible 
ways  the  intellectual  faculties  of  every  human  being.  No 
doubt  a  man  with  a  torpid  mind,  if  his  social  affections  and 
sympathies  ai-e  well  developed,  will  be  led  to  good  actions, 
and  may  have  a  fairly  sensitive  conscience.  But  whatever 
renders  the  imagination  more  vivid  and  strengthens  the 
habit  of  recalling  and  comparing  past  impressions  will  make 
the  conscience  more  sensitive,  and  may  even  somewhat 
compensate  for  weak  social  affections  and  sympathies. 

The  moral  nature  of  man  has  reached  its  present  stand 
ard  partly  through  the  advancement  of  his  reasoning  powers 
and  consequently  of  a  just  public  opinion,  but  especially 
from  his  sympathies  having  been  rendered  more  tender  ana 
widely  diffused  through  the  effects  of.  habit,  example, 
instruction  and  reflection.  It  is  not  improbable  that  after 
long  practice  virtuous  tendencies  may  be  inherited.  With 
the  more  civilized  races  the  conviction  of  the  existence  of 
an  all-seeing  Deity  has  had  a  potent  influence  on  the 


700  THE  BESCKNT  OF  MAN. 

advance  of  morality.     Ultimately  man  does  not  accept  the 
praise  or  blame  of  his  fellows  as  his  sole  guide,  though 
few  escape  this  influence,  but  his  liabitual  convictions,  con- 
trolled by  reason,  afford  him  the  safest  rule.     His  con- 
science  tlien   becomes   the   supreme   judge  and   monitor. 
i    Nevertheless,  the  first  foundation  or  origin  of  the  moral  sense 
I    lies  in  the  social  instincts,  including  sympathy;  and  these 
\    instincts  no  doubt  were  primarily  gained,  as  in  the  case  of 
\  the  lower  animals,  through  natural  selection. 

The  belief  in  God  has  often  been  advanced  as  not  only 
the  greatest  but  the  most  complete  of  all  the  distinctions 
between  man  and  the  lower  animals.  It  is,  however,  im- 
possible, as  we  have  seen,  to  maintain  that  this  belief  is 
innate  or  instinctive  in  man.  On  the  other  hand,  a  belief 
in  all-pervading  spiritual  agencies  seems  to  be  universal; 
and  apparently  follows  from  a  considerable  advance  in 
man's  reason,  and  from  a  still  greater  advance  in  his 
faculties  of  imagination,  curiosity  and  wonder.  I  am 
aware  that  the  assumed  instinctive  belief  in  God  has  been 
used  by  many  persons  as  an  argument  for  His  existence. 
But  this  is  a  rash  judgment,  as  we  should  tlius  be  compelled 
to  believe  in  the  existence  of  many  cruel  and  malignant 
spirits,  only  a  little  more  powerful  than  man;  for  the 
belief  in  them  is  far  more  general  than  in  a  beneficient  Deity. 
The  idea  of  a  universal  and  beneficient  Creator  does  not 
seem  to  arise  in  the  mind  of  man  until  he  has  been  elevated 
by  long-continued  culture. 

He  who  believes  in  the  advancement  of  man  from  some 
low  organized  form  will  naturally  ask.  How  does  this  bear 
on  the  belief  in  the  immortality  of  the  soul?  The  barbar- 
ous races  of  man,  as  Sir  J.  Lubbock  has  shown,  possess  no 
clear  belief  of  this  kind ;  but  arguments  derived  from  the 
primeval  beliefs  of  savages  are,  as  we  have  just  seen,  of 
little  or  no  avail.  Few  persons  feel  any  anxiety  from  the 
impossibility  of  determining  at  what  precise  period  in  the 
development  of  the  individual,  from  the  first  trace  of  a 
minute  germinal  vesicle,  man  becomes  an  immortal  being; 
and  there  is  no  greater  cause  for  anxiety  because  the 
period  cannot  possibly  be  determined  in  the  gradually 
ascending  organic  scale.* 

*Tbe  Kev.  J.  A.  Picton  gives  a  discussion  to  this  effect  in  his 
"  New  Theories  and  the  Old  Faith,"  1870. 


GENERAL  SUMMARY  AND  CONCLUSION.        701 

I  am  aware  that  the  conclusions  arrived  at  in  tliis  work 
will  be  denounced  by  some  as  highly  irreligious;  but  he 
who  denounces  them  is  bound  to  show  why  it  is  more  irre- 
ligious to  explain  the  origin  of  man  as  a  distinct  species  by 
descent  from  some  lower  form,  through  the  laws  of  varia- 
tion and  natural  selection,  than  to  explain  the  birth  of  the 
individual  through  the  laws  of  ordinary  reproduction. 
The  birth  both  of  the  species  and  of  the  individual  are  equally 
parts  of  that  grand  sequence  pf  events,  which  our  minds 
refuse  to  accept  as  the  result  of  blind  chance.  The  under- 
standing revolts  at  such  a  conclusion,  whether  or  not  we 
are  able  to  believe  that  every  slight  variation  of  structure, 
the  union  of  each  pair  in  marriage,  the  dissemination  of 
each  seed,  and  other  such  events  have  all  been  ordained  for 
some^ecial  purpose. 

Sexual  selection  has  been  treated  at  great  length  in  this 
work;  for,  as  I  have  attempted  to  show,  it  has  played  an 
imp£tt;tant  part  in  the  history  of  the  organic  world.  I  am 
aware  that  much  remains  doubtful,  but  I  have  endeavored 
to  give  a  fair  view  of  the  whole  case.  In  the  lower  divis- 
ions of  the  animal  kingdom  sexual  selection  seems  to  have 
done  nothing;  such  animals  are  often  affixed  for  life  to  the 
same  spot,  or  have  the  sexes  combined  in  the  same  indi- 
vidual, or,  what  is  still  more  important,  their  perceptive  and 
intellectual  faculties  are  not  sufficiently  advanced  to  allow 
of  the  feelings  of  love  and  jealousy,  or  of  the  exertion  of 
choice.  When,  however,  we  come  to  the  Arthropoda  and 
Vertebrata,  even  to  the  lowest  classes  in  these  two  great 
sub-kingdoms,  sexual  selection  has  effected  much. 

In  the  several  great  classes  of  the  animal  kingdom — in 
mammals,  birds,  reptiles,  fishes,  insects  and  even  crusta- 
ceans— the  differences  between  the  sexes  follow  nearly  the 
same  rules.  The  males  are  almost  always  the  wooers;  and 
they  alone  are  armed  with  special  weapons  for  fighting  with 
their  rivals.  They  are  generally  stronger  and  larger  than 
the  females,  and  are  endowed  with  the  requisite  qualities 
of  courage  and  pugnacity.  They  are  provided,  either 
exclusively  or  in  a  much  higher  degree  than  the  females, 
with  organs  for  vocal  or  instrumental  music,  and  with 
odoriferous  glands.  They  are  ornamented  with  infinitely 
diversified  appendages,  and  with  the  most  brilliant  or  con- 
spicuous colors,  often  arranged  in  elegant  patterns,  while 


702  THE  DESCENT  OF  MAN, 

the  females  are  unadorned.  AVhen  tlie  sexes  differ  in  more 
important  structures  it  is  the  male  which  is  provided  with 
special  sense-organs  for  discovering  the  female,  with  loco- 
motive organs  for  reaching  her,  and  often  with  prehensile 
organs  for  holding  her.  These  various  structures  for  charm- 
ing or  securing  the  female  are  often  developed  in  the  male 
during  only  part  of  the  year;  namely,  the  breeding-season. 
They  have  in  many  cases  been  more  or  less  transferred  to 
the  females;  and  in  the  latter  case  they  often  appear  in  her 
as  mere  rudiments.  They  are  lost  or  never  gained  by  tlie 
males  after  emasculation.  Generally  they  are  not  developed 
in  the  male  during  early  youth,  but  appear  a  short  time 
before  the  age  for  reproduction.  Hence,  in  most  cases  the 
young  of  both  sexes  resemble  each  other;  and  the  female 
somewhat  resembles  her  young  offspring  throughout  life. 
In  almost  every  great  class  a  few  anomalous  cases  occur, 
where  there  has  been  an  almost  complete  transposition  of 
the  characters  proper  to  the  two  sexes;  the  females  assum- 
ing characters  which  properly  belong  to  the  males.  This 
surprising  uniformity  in  the  laws  regulating  the  differences 
between  the  sexes  in  so  many  and  such  widely  separated 
classes  is  intelligible  if  we  admit  the  action  of  one  common 
cause;  namely,  sexual  selection. 

Sexual  selection  depends  on  the  success  of  certain  indi- 
viduals over  others  of  the  same  sex,  in  relation  to  the  prop- 
agation of  the  species;  while  natural  selection  depends  on 
the  success  of  both  sexes,  at  all  ages,  in  relation  to  the  gen- 
eral conditions  of  life.  The  sexual  struggle  is  of  two 
kinds;  in  the  one  it  is  between  the  individuals  of  the  same 
sex,  generally  the  males,  in  order  to  drive  away  or  kill  their 
rivals,  the  females  remaining  passive;  while  in  the  other, 
the  struggle  is  likewise  between  the  individuals  of  the 
same  sex,  in  order  to  excite  or  charm  those  of  the  opposite 
sex,  generally  the  females,  which  no  longer  remain  passive, 
but  select  the  more  agreeable  partners.  This  latter  kind 
of  selection  is  closely  analogous  to  that  which  man  unin- 
tentionally, yet  effectually,  brings  to  bear  on  his  domesti- 
cated productions,  when  he  preserves  during  a  long  period 
the  most  pleasing  or  useful  individuals,  without  any  wish  to 
modify  the  breed. 

The  laws  of  inheritance  determine  whether  characters 
gained  through  sexual  selection  by  either  sex  shall  be  trans- 
mitted to  the  same  sex^  or  to  both;  as  well  as  the  age  at 


GENEUAL  SUMMARY  AND  CONCLUSION.        703 

which  they  shall  be  developed.  It  appears  that  variations 
arising  late  in  life  are  commonly  transmitted  to  one  and 
the  same  sex.  Variability  is  the  necessary  basis  for  the 
action  of  selection  and  is  wholly  independent  of  it.  It  fol- 
lows from  this,  that  variations  of  the  same  general  nature 
have  often  been  taken  advantage  of  and  accumulated 
through  sexual  selection  in  relation  to  the  propagation  of 
the  species,  as  well  as  through  natural  selection  in  relation 
to  the  general  purposes  of  life.  Hence  secondary  sexual 
characters,  when  equally  transmitted  to  both  sexes,  can  be 
distinguished  from  ordinary  specific  characters  only  by  the 
light  of  analogy.  The  modifications  acquired  through 
sexual  selection  are  often  so  strongly  pronounced  that  the 
two  sexes  have  frequently  been  ranked  as  distinct  species, 
or  even  as  distinct  genera.  Such  strongly  marked  differ- 
ences must  be  in  some  manner  highly  important;  and  we 
know  that  they  have  been  acquired  in  some  instances  at 
the  cost  not  only  of  inconvenience,  but  of  exposure  to 
actual  danger. 

The  belief  in  the  power  of  sexual  selection  rests  chiefly 
on  the  following  considerations.  Certain  characters  are 
confined  to  one  sex;  and  this  alone  renders  it  probable  that 
in  most  cases  they  are  connected  with  the  act  of  reproduc- 
tion. In  innumerable  instances  these  characters  are  fully 
developed  only  at  maturity,  and  often  during  only  a  part  of 
the  year,  which  is  always  the  breeding- season.  The  males 
(passing  over  a  few  exceptional  cases)  are  the  more  active 
in  courtship;  they  are  the  better  armed,  and  are  rendered 
the  more  attractive  in  various  ways.  It  is  to  be  especially 
observed  that  the  males  display  their  attractions  with 
elaborate  care  in  the  presence  of  the  females;  and  that 
they  rarely  or  never  display  them  excepting  during  the 
season  of  love.  It  is  incredible  that  all  this  should  be  pur- 
poseless. Lastly,  we  have  distinct  evidence  with  some 
quadrupeds  and  birds  that  the  individuals  of  one  sex  are 
capable  of  feeling  a  strong  antipathy  or  preference  for 
certain  individuals  of  the  other  sex. 

Bearing  in  mind  these  facts  and  the  marked  results  of 
man's  unconscious  selection  when  applied  to  domesticated 
animals  and  cultivated  plants  it  seems  to  me  almost  cer- 
tain that  if  the  individuals  of  one  sex  were  during  a  long 
series  of  generations  to  prefer  pairing  with  certain  indi- 
viduals pi  the  other  sex^  characterized  in  some  peculiar 


704  THE  DESCENT  OF  MAN. 

manner,  the  offspring  would  slowly  but  surely  become 
modified  in  this  same  manner.  I  have  not  attempted  to 
conceal  that,  excepting  when  the  males  are  more  numerous 
than  the  females,  or  when  polygamy  prevails,  it  is  doubtful 
how  the  more  attractive  males  succeed  in  leaving  a  larger 
number  of  offspring  to  inherit  their  superiority  in  orna- 
ments or  other  charms  than  the  less  attractive  males;  but 
I  have  shown  that  this  would  probably  follow  from  the 
females — especially  the  more  vigorous  ones,  which  would 
be  the  first  to  breed — preferring  not  only  the  more  attract- 
ive but  at  the  same  time  the  more  vigorous  and  victorious 
males. 

Although  we  have  some  positive  evidence  that  birds 
appreciate  bright  and  beautiful  objects,  as  with  the  bower- 
birds  of  Australia,  and  althougli  they  certainly  appreciate 
the  power  of  song,  yet  I  fully  admit  that  it  is  astonishing 
that  the  females  of  many  birds  and  some  mammals  should 
be  endowed  with  sufficient  taste  to  appreciate  ornaments 
which  we  have  reason  to  attribute  to  sexual  selection;  and 
this  is  even  more  astonishing  in  the  case  of  reptiles,  fish 
and  insects.  But  we  really  know  little  about  the  minds  of 
the  lower  animals.  It  cannot  be  supposed,  for  instance,  that 
male  birds  of  paradise  or  peacocks  should  take  such  pains 
in  erecting,  spreading  and  vibrating  their  beautiful  plumes 
before  the  females  for  no  purpose.  AVe  should  remember 
the  fact  given  on  excellent  authority  in  a  former  chapter 
that  several  peahens,  when  debarred  from  an  admired  male, 
remained  widows  during  a  whole  season  rather  than  pair 
with  another  bird. 

Nevertheless,  1  know  of  no  fact  in  natural  history  more 
wonderful  than  that  the  female  Argus  pheasant  should 
appreciate  the  exquisite  shading  of  the  ball-and-socket 
ornaments  and  the  elegant  patterns  on  the  wing-feathers 
of  the  male.  He  who  thinks  that  the  male  was  created  as 
he  now  exists  must  admit  that  the  great  plumes,  which 
prevent  the  wings  from  being  used  for  flight  and  which 
are  displayed  during  courtship  and  at  no  other  time  in  a 
manner  quite  peculiar  to  this  one  species,  were  given  to 
him  as  an  ornament.  If  so,  he  must  likewise  admit  that 
the  female  was  created  and  endowed  with  the  capacity  of 
appreciating  such  ornaments.  I  differ  only  in  the  convic- 
tion that  the  male  Argus  pheasant  acquired  his  beauty 
gradually,  through  the  preference  of  the   females  during 


GENERAL  SUMMARY  AND  CONCLUSION        705 

many  generations  for  the  more  highly  ornamented  males; 
the  esthetic  capacity  of  the  females  having  been  advanced 
through  exercise  or  habit  just  as  our  own  taste  is  gradually 
improved.  In  the  male,  through  the  fortunate  chance  of  a 
few  feathers  being  left  unchanged,  we  can  distinctly  trace 
how  simple  spots  with  a  little  fulvous  shading  on  one  side 
may  have  been  developed  by  small  steps  into  the  wonderful 
ball-and-socket  ornaments;  and  it  is  probable  that  they 
were  actually  thus  developed. 

Every  one  who  admits  the  principle  of  evolution,  and 
yet  feels  great  difficulty  in  admitting  that  female  mammals, 
birds,  reptiles  and  fish,  could  have  acquired  the  high  taste 
implied  by  the  beauty  of  the  males,  and  which  generally 
coincides  with  our  own  standard,  should  reflect  that  the 
nerve -cells  of  the  brain  in  the  highest  as  well  as  in  the 
lowest  members  of  the  Vertebrate  series,  are  derived  from 
those  of  the  common  progenitor  of  this  great  kingdom. 
For  we  can  thus  see  how  it  has  come  to  pass  that  certain 
mental  faculties,  in  various  and  widely  distinct  groups  of 
animals,  have  been  developed  in  nearly  the  same  manner 
and  to  nearly  the  same  degree. 

The  reader  who  has  taken  the  trouble  to  go  through  the 
several  cnapters  devoted  to  sexual  selection  will  be  able  to 
judge  how  far  the  conclusions  at  which  I  have  arrived  are 
supported  by  sufficient  evidence.  If  he  accepts  these  con 
elusions  he  may,  I  think,  safely  extend  them  to  mankind; 
but  it  would  be  superfluous  here  to  repeat  what  I  have  so 
lately  said  on  the  manner  in  which  sexual  selection  appar- 
ently has  acted  on  man,  both  on  the  male  and  female  side, 
causing  the  two  sexes  to  differ  in  body  and  mind,  and  the 
several  races  to  differ  from  each  other  in  various  characters, 
as  well  as  from  their  ancient  and  lowly  organized  pro- 
genitors. 

He  who  admits  the  principle  of  sexual  selection  will  be 
led  to  the  remarkable  conclusion  that  the  nervous  system 
not  only  regulates  most  of  the  existing  functions  of  the 
body,  but  has  indirectly  influenced  the  progressive  develop- 
ment of  various  bodily  structures  and  of  certain  menta} 
qualities.  Courage,  pugnacity,  perseverance,  strength  an(^ 
size  of  body,  weapons  of  all  kinds,  musical  organs,  both\ 
vocal  and  instrumental,  bright  colors  and  ornamental  ap- 
pendages, have  all  been  indirectly  gained  by  the  one  sex  or 
the  other,  through  the  exertion  of  choice,  the  influence  of 


706  THE  DESCENT  OF  MAN, 

love  and  jealousy  and  the  appreciation  of  the  beautiful  in 
Bound,  color  or  form;  and  these  powers  of  the  mind  mani- 
festly depend  on  the  development  of  the  brain. 

Man  scans  with  scrupulous  care  the  character  and  pedi- 
gree of  his  horses,  cattle  and  dogs  before  he  matches  them; 
but  when  he  comes  to  his  own  marriage  he  rarely,  or  never, 
takes  any  such  care.  He  is  impelled  by  nearly  the  same 
motives  as  the  lower  animals,  when  they  are  left  to  their 
own  free  choice,  though  he  is  in  so  far  superior  to  them 
that  he  highly  values  mental  charms  and  virtues.  On  the 
other  hand  he  is  strongly  attracted  by  mere  wealth  or  rank. 
Yet  he  might  by  selection  do  something  not  only  for  the 
bodily  constitution  and  frame  of  his  offspring,  but  for  their 
intellectual  and  moral  qualities.  Both  sexes  ought  to  re- 
frain from  marriage  if  they  are  in  any  marked  degree  in- 
ferior in  body  or  mind;  but  such  hopes  are  Utopian  and 
will  never  be  even  partially  realized  until  the  laws  of  in- 
heritance are  thoroughly  known.  'Every  one  does  good 
service,  who  aids  toward  this  end.  When  the  principles  of 
breeding  and  inheritance  are  better  understood,  we  shall 
not  hear  ignorant  memberc  of  our  legislature  rejecting  with 
scorn  a  plan  for  ascertaining  v^hether  or  not  consanguineous 
marriages  are  injurious  to  man. 

The  advancement  of  the  welfare  of  mankind  is  a  most 

intricate  problem;  all  ought  to  refrain  from  marriage  who 

cannot  avoid  abject  poverty  for  their  children;  for  poverty 

is  not  only  a  great  evil,  but  tends  to  its  own  increase  by 

leading  to  recklessness  in  marriage.     On  the  other  hand, 

as  Mr.  Galton  has  remarked,  if  the  prudent  avoid  marriage, 

while  the  reckless  marry,  the   inferior  members  tend  to 

supplant  the  better  members  of  society.     Man,  like  every 

other  animal,  has  no  doubt  advanced  to  his  present  high 

condition  through  a  struggle  for  existence  consequent  on 

his  rapid  multiplication;  and  if  he  is  to  advance  still  higher, 

it  is  to  be  feared  that  he  must  remain  subject  to  a  severe 

struggle.     Otherwise  he  would  sink  into  indolence,  and  the . 

more  gifted  men  would  not  be  more  successful  in  the  battle/ 

d^        I  of  life  than  the  less  gifted.     Hence  our  natural  rate  of 

'N        I  increase,  though  leading  to  many  and  obvious  evils,  must.. 

not  be  greatly  diminished  by  any  means.     There  shoul(' 

be  open  competition  for  all  men;  and  the  most  able  should 

not   be  prevented  by  laws   or  customs   from   succeeding 


GENERAL  SUMMARY  AND  CONCLUSION.        707 

best  and  rearing  the  largest  number  of  offspring.  Impor- 
tant as  the  struggle  for  existence  has  been  and  even  still  is, 
yet  as  far  as  the  highest  part  of  man's  nature  is  concerned 
there  are  other  agencies  more  important.  For  the  moral 
qualities  are  advanced,  either  directly  or  indirectly,  much 
more  through  the  effects  of  habit,  the  reasoning  powers, 
instruction,  religion,  etc.,  than  through  natural  selection; 
though  to  this  latter  agency  may  be  safely  attributed  the 
social  instincts  which  afforded  the  basis  for  the  develop- 
ment of  the  moral  sense. 

The  main  conclusion  arrived  at  in  this  work,  namely, 
that  man  is  descended  from  some  lowly  organized  form, 
will,  I  regret  to  think,  be  highly  distasteful  to  many.  But 
there  can  hardly  be  a  doubt  that  we  are  descended  from 
barbarians.  The  astonishment  which  I  felt  on  first  seeing 
a  party  of  Fuegians  on  a  wild  and  broken  shore  will  never 
be  forgotten  by  me,  for  the  reflection  at  once  rushed  into 
my  mind  —  such  were  our  ancestors.  These  men  were 
absolutely  naked  and  bedaubed  with  paint,  their  long  hair 
was  tangled,  their  mouths  frothed  with  excitement,  and 
their  expression  was  wild,  startled  and  distrustful.  They 
possessed  hardly  any  arts,  and  like  wild  animals  lived  on 
what  they  could  catch;  they  had  no  government,  and  were 
merciless  to  every  one  not*  of  their  own  small  tribe.  He 
who  hafi  seen  a  savage  in  bis  native  land  will  not  feel  much 
shame,  if  forced  to  acknowledge  that  the  blood  of  some 
more  humble  creature  flows  in  his  veins.  For  my  own  part 
I  would  as  soon  be  descended  from  that  heroic  little  mon- 
key who  braved  his  dreaded  enemy  in  order  to  save  the 
life  of  his  keeper,  or  from  that  old  baboon,  who,  descend- 
ing from  the  mountains,  carried  away  in  triumph  his 
young  comrade  from  a  crowd  of  astonished  dogs — as  from 
a  savage  who  delights  to  torture  his  enemies,  offers  up 
bloody  sacrifices,  practices  infanticide  without  remorse, 
treats  his  wives  like  slaves,  knows  no  decency,  and  is 
haunted  by  the  grossest  superstitions. 

Man  may  be  excused  for  feeling  some  pride  at  having 
risen,  though  not  through  his  own  exertions,  to  the  very 
summit  of  the  organic  scale;  and  the  fact  of  his  having 
thus  risen,  instead  of  having  been  aboriginally  placed  there, 
may  give  him  hope  for  a  still  higher  destiny  in  the  distant 
future.    But  we  are  not  here  concerned  with  hoi^es  or  fears. 


708  THE  DESCENT  OF  MAN. 

only  with  the  truth  as  far  as  our  reason  permits  us  to  dis- 
cover it;  and  I  have  given  the  evidence  to  tlie  best  of  my 
ability.  We  must,  however,  acknowledge,  as  it  seems  to 
me,  tliat  man,  with  all  his  noble  qualities,  with  sympathy 
which  feels  for  the  most  debased,  with  benevolence  which 
extends  not  only  to  other  men  but  to  the  humblest  living 
creature,  with  his  godlike  intellect  which  has  penetrated 
into  the  movements  and  constitution  of  the  solar  system — 
with  all  these  exalted  powers — man  still  bears  in  his  bodily 
frame  the  indelible  stamp  of  his  lowly  origin. 


SUPPLEMENTAL  NOTE,  709 


SUPPLEMENTAL    NOTE 

ON 

SEXUAL   SELECTION    IN    RELATION  TO    MONKEYS. 

[Reprinted  from  Nature,  November  2, 1876,  p.  18.] 

In  the  discussion  on  sexual  selection  in  my  "  Descent  of 
Man;"  no  case  interested  and  perplexed  me  so  much  as  the 
brightly  colored  hinder  ends  and  adjoining  parts  of  certain 
monkeys.  As  these  parts  are  more  brightly  colored  in  one 
sex  than  the  other,  and  as  they  become  more  brilliant 
during  the  season  of  love,  I  concluded  that  the  colors  had 
been  gained  as  a  sexual  attraction.  I  was  well  aware  that 
I  thus  laid  myself  open  to  ridicule;  though  in  fact  it  is  not 
more  surprising  that  a  monkey  should  display  his  bright- 
red  hinder  end  than  that  a  peacock  should  display  his  mag- 
nificent tail.  I  had,  however,  at  that  time  no  evidence  of 
monkeys  exhibiting  this  part  of  their  bodies  during  their 
courtship  ;  and  such  display  in  the  case  of  birds 
affords  the  best  evidence  that  the  ornaments  of  the 
males  are  of  service  to  them  by  attracting  or 
exciting  the  females.  I  have  lately  read  an  article 
by  Joh.  von  Fischer,  of  Gotha,  published  in  '^Der 
Zoologische  Garten,"  April,  1876,  on  the  expression  of 
monkeys  under  various  emotions,  which  is  well  worthy  of 
study  by  any  one  interested  in  the  subject,  and  which 
shows  that  the  author  is  a  careful  and  acute  observer.  In 
this  article  there  is  an  account  of  the  behavior  of  a  young 
male  mandrill  when  he  first  beheld  himself  in  a  looking- 
glass,  and  it  is  added  that  after  a  time  he  turned  round 
and  presented  his  red  hinder  end  to  the  glass.  Accord- 
ingly I  wrote  to  Herr  J.  von  Fischer  to  ask  what  he  sup- 
posed was  the  meaning  of  this  strange  action,  and  he  has 
sent  me  two  long  letters  full  of  new  and  curious  details, 
which  will,  I  hope,  be  hereafter  published.     He  says  that 


1^10  THE  DESCENT  OP  liAif. 

lie  was  himself  at  first  perplexed  by  the  above  action,  and 
was  thus  led  carefully  to  observe  several  individuals  of 
various  other  species  of  monkeys,  which  he  has  long  kept 
in  his  house.  He  finds  that  not  only  the  mandrill  (Cyno- 
ceplialus  mormon)  but  the  drill  (C.  leucophmus)  and  three 
other  kinds  of  baboons  [C.hamadryas  sphinx 'dndbabo2ii?i)y 
also  Cynopitliecus  niger,  and  Macacus  rhesus  and  7iemes- 
trinus,  turn  this  part  of  their  bodies,  which  in  all  these 
species  is  more  or  less  brightly  colored,  to  him  when  they 
are  pleased,  and  to  other  persons  as  a  sort  of  greeting.  He 
took  pains  to  cure  a  Macacus  7'hesus,  which  he  had  kept 
for  five  years,  of  this  indecorous  habit,  and  at  last  suc- 
ceeded. These  monkeys  are  particularly  apt  to  act  in  this 
manner,  grinning  at  the  same  time,  when  first  introduced 
to  a  new  monkey,  but  often  also  to  their  old  monkey 
friends;  and  after  this  mutual  display  they  begin  to  play 
together.  The  young  mandrill  ceased  spontaneously  after 
a  time  to  act  in  this  manner  toward  his  master,  Von 
Fischer,  but  continued  to  do  so  toward  persons  who  were 
strangers  and  to  new  monkeys.  A  young  Cynopithecus 
niger  never  acted,  excepting  on  one  occasion,  in  this  way 
toward  his  master,  but  frequently  toward  strangers, 
and  continues  to  do  so  up  to  the  present  time.  From 
these  facts  Von  Fischer  concludes  that  the  monkeys 
which  behaved  in  this  manner  before  a  looking-ghiss 
(viz.,  the  mandrill,  drill,  Cynopithecus  niger ^  Maca- 
cus rhesus  and  neinestrinus)  acted  as  if  their  refiec- 
tion  were  a  new  acquaintance.  The  mandrill  and  drill, 
which  have  their  hinder  ends  especially  ornamented, 
display  it  even  while  quite  young,  more  frequently  and 
more  ostentatiously  than  do  the  other  kinds.  Next  in 
order  comes  Cynocephalus  hamadryas,  while  the  other 
species  act  in  this  manner  seldomer.  The  individuals, 
however,  of  the  same  species  vary  in  this  respect,  and  some 
which  were  very  shy  never  displayed  their  hinder  ends.  It 
deserves  especial  attention  that  Von  Fischer  has  never 
seen  any  species  purposely  exhibit  the  hinder  part  of  its 
body,  if  not  at  all  colored.  This  remark  applies  to  many 
individuals  of  Macacus  cynomolgus  and  Cercocebus  radi- 
atus  (which  is  closely  allied  to  M.  rhesus),  to  three  species 
of  Cercopithecus  and  several  American  monkeys.  The 
habit  of  turning  the  hinder  ends  as  a  greeting  to  an  old 
friend  or  new  acquaintance,  which  seems  to  us  so  odd,  is 


SUPPLEMENTAL  NOf^. 

iiot  really  more   so  than  the  habits  of  many  savages, 
instance  that  of  rubbing  their  bellies  with  their  hands, 
rubbing  noses  together.     The  habit  with  the  mandrill  ai 
drill  seems  to  be  instinctive  or  inherited,  as  it  was  foUowe 
by  very  young  animals;  but  it  is  modified  or  guided,  like 
so  many  other  instincts,  by  observation,  for  Von  Fischer 
says  that  they  take  pains  to  make  their  display  fully;  and 
if  made  before  two  observers,  they  turn  to  him  who  seems 
to  pay  the  most  attention. 

With  respect  to  the  origin  of  the  habit.  Von  Fischer 
remarks  that  his  monkeys  like  to  have  their  naked  hinder 
ends  patted  or  stroked,  and  that  they  then  grunt  with 
pleasure.  They  often  also  turn  this  part  of  their  bodies 
to  other  monkeys  to  have  bits  of  dirt  picked  off,  and  so 
no  doubt  it  would  be  with  respect  to  thorns.  But  the 
habit  with  adult  animals  is  connected  to  a  certain  extent 
with  sexual  feelings,  for  Von  Fischer  watched  through  a 
glass  door  a  female  Cynopithemis  niger,  and  she,  during 
several  days,  **umdrehte  und  dem  Mannchen  mit  gur- 
gelnden  Tonen  die  stark  gerothete  Sitzflache  zeigte,  was 
ich  friiher  nie  an  diesem  Thier  bemerkt  hatte.  Beim 
Anblick  dieses  Gegenstandes  erregte  sich  das  Mannchen 
sichtlich,  denn  es  polterte  heftig  an  den  Staben,  ebenfalls 
gurgelnde  Laute  ausstossend.^'  As  all  the  monkeys  which 
have  the  hinder  parts  of  their  bodies  more  or  less  brightly 
colored  live,  according  to  Von  Fischer,  in  open  rocky 
places,  he  thinks  that  these  colors  serve  to  render  one  sex 
conspicuous  at  a  distance  to  the  other;  but  as  monkeys  are 
such  gregarious  animals  I  should  have  thought  that  there 
was  no  need  for  the  sexes  to  recognize  each  other  at  a  dis- 
tance. It  seems  to  me  more  probable  that  the  bright 
colors,  whether  on  the  face  or  hinder  end,  or,  as  in  the 
mandrill,  on  both,  serve  as  a  sexual  ornament  and  attrac- 
tion. Anyhow,  as  we  now  know  that  monkeys  have  the 
habit  of  turning  their  hinder  ends  toward  other  monkeys, 
it  ceases  to  be  at  all  surprising  that  it  should  have  been 
this  part  of  their  bodies  which  has  been  more  or  less 
decorated.  The  fact  that  it  is  only  the  monkeys  thus 
chai*acterized  which,  as  far  as  at  present  known,  act  in  this 
manner  as  a  greeting  toward  other  monkeys  renders  it 
doubtful  whether  the  habit  was  first  acquired  from  some 
independent  cause,  and  that  afterward  the  parts  in  ques- 
tion were  colored  as  a  sexual  ornament;  or  whether  the 


THE  DESCENT  OF  MAN. 

ling  and  the  liabit  of  turning  round  were  first  acquired 
jugh  variation  and  sexual  selection,  and  that  afterward 
3  habit  was  retained  as  a  sign  of  pleasure  or  as  a  greet- 
g  through  the  principle  of  inherited  association.     This 
principle  apparently  comes  into  play  on  many  occasions; 
thus  it  is  generally  admitted  that  the  songs  of  birds  serve 
mainly  as  an  attraction  during  the  season  of  love,  and  that 
the  leks,  or  great  congregations  of  the  black  grouse,  are 
connected  with  their  courtsliip;  but  the  habit  of  singing 
has  been  retained  by  some  birds  when  they  feel  happy,  for 
instance,  by  the  common  robin,  and  the  iiabit  of  congre- 
gating has  been  retained  by  the  black  grouse  during  other 
seasons  of  the  year. 

I  beg  leave  to  refer  to  one  other  point  in  relation  to 
sexual  selection.  It  has  been  objected  that  this  form  of 
selection,  as  far  as  the  ornaments  of  the  males  are  con- 
cerned, implies  that  all  the  females  within  the  same  dis- 
trict must  possess  and  exercise  exactly  the  same  taste.  It 
should,  however,  be  observed,  in  the  first  place,  that 
although  the  range  of  variation  of  a  species  may  be  very 
large  it  is  by  no  means  indefinite.  I  have  elsewhere  given  a 
good  instance  of  this  fact  in  the  pigeon,  of  which  there  are 
at  least  a  hundred  varieties  differing  widely  in  their  colors, 
and  at  least  a  score  of  varieties  of  the  fowl  differing  in 
the  same  kind  of  way;  but  the  range  of  color  in  tliese 
two  species  is  extremely  distinct.  Therefore  the  females  of 
natural  species  cannot  have  an  unlimited  scope  for  their 
taste.  In  the  second  place,  I  presume  that  no  supporter  of 
the  principle  of  sexual  selection  believes  that  the  females 
select  particular  points  of  beauty  in  the  males;  they  are 
merely  excited  or  attracted  in  a  greater  degree  by  one  male 
than  by  another,  and  this  seems  often  to  depend,  especially 
with  birds,  on  brilliant  coloring.  Even  man,  excepting 
perhaps  an  artist,  does  not  analyze  the  slight  differences  in 
the  features  of  the  woman  whom  he  may  admire,  on  which 
her  beauty  depends.  The  male  mandrill  has  not  only  the 
hinder  end  of  his  body,  but  his  face  gorgeously  colored  and 
marked  with  oblic^ue  ridges,  a  yellow  beard  and  other  orna- 
ments. We  may  infer  from  what  we  see  of  the  variation 
of  animals  under  domestication  that  the  above  several 
ornaments  of  the  mandrill  were  gradually  acquired  by  one 
individual  varying  a  little  in  one  way  and  another  indi- 
vidual in  another  way.     The  males  which  were  the  hand- 


SUPPLEMENTAL  NOTE.  713 

somest  or  the  most  attractive  in  any  manner  to  the  females 
would  pair  oftenest,  and  would  leave  rather  more  offspring 
than  other  males.  The  offspring  of  the  former,  although 
variously  intercrossed,  would  either  inherit  the  peculiarities 
of  their  fathers  or  transmit  an  increased  tendency  to  vary 
in  the  same  manner.  Consequently  the  whole  body  of 
males  inhabiting  the  same  country  would  tend  from  the 
effects  of  constant  intercrossing  to  become  modified  almost 
uniformly,  but  sometimes  a  little  more  in  one  character  and 
sometimes  in  another,  though  at  an  extremely  slow  rate;  all 
ultimately  being  thus  rendered  more  attractive  to  the 
females.  The  process  is  like  that  which  I  have  called 
unconscious  selection  by  man,  and  of  which  I  have  given 
several  instances.  In  one  country  the  inhabitants  value  a 
fleet  or  light  dog  or  horse,  and  in  another  country  a  heavier 
and  more  powerful  one;  in  neither  country  is  there  any 
selection  of  individual  animals  with  lighter  or  stronger 
bodies  and  limbs;  nevertheless,  after  a  considerable  lapse 
of  time,  the  individuals  are  found  to  have  been  modified  in 
the  desired  manner  almost  uniformly,  though  differently  in 
each  country.  In  two  absolutely  distinct  countries  inhab- 
ited by  the  same  species,  the  individuals  of  which  can 
never,  during  long  ages,  have  intermigrated  and  inter- 
crossed, and  where,  moreover,  the  variations  will  probably 
not  have  been  identically  the  same,  sexual  selection  might 
cause  the  males  to  differ.  Nor  does  the  belief  appear  to 
me  altogether  fanciful  that  two  sets  of  females,  surrounded 
by  a  very  different  environment,  would  be  apt  to  acquire 
somewhat  different  tastes  with  respect  to  form,  sound  or 
color.  However  this  may  be,  I  have  given  in  my  '^  Descent 
of  Man"  instances  of  closely  allied  birds  inhabiting  dis- 
tinct countries,  of  which  the  young  and  the  females  cannot 
be  distinguished,  while  the  adult  males  differ  considerably, 
and  this  may  be  attributed  with  much  probability  to  the 
action  of  sexual  selection. 


INDEX. 


Abbott,  C,  on  the  battles  of  seals,  571. 

Abductor  of  the  fifth  metatarsal,  presence  of,  in  man,  47. 

Abercrombie,  Dr. ,  on  disease  of  the  brain  affecting  speech,  100. 

Abipones,  marriage  customs  of  the,  683. 

Abortion,  prevalence  of  the  practice  of,  52. 

Abou-Simbel,  caves  of,  191. 

Ahramis  brama,  282. 

Abstraction,  power  of,  in  animals,  93. 

Acalles,  stridulation  of,  346. 

Acanthodactylus  capensis,  sexual  differences  of  color  in,  405. 

Accentor  modularis,  539. 

Acclimatization,  difference  of,  in  different  races  of  men,  191, 

Achetidae,  stridulation  of  the,  320,  321,  323;  rudimentary  stridulat- 
ing  organs  in  female,  326. 

Acilius  snleatus,  elytra  of  the  female,  313. 

Acomus,  development  of  spurs  in  the  female  of,  512. 

Acridiidae,  stridulation  of  the,  320,  324;  rudimentary  stridulating 
organs  in  female,  326. 

Acromio-basilar  muscle,  and  quadrupetal  gait,  47. 

Acting,  203. 

Actinm,  bright  colors  of,  294. 

Adams,  Mr.,  migration  of  birds,  122;  intelligence  of  nut-hatch, 
466;  on  the  Borribycilla  carolinensis,  525. 

Admiral  butterfly,  353. 

Adoption  of  the  young  of  other  animals  by  female  monkeys,  79. 

Advancement  in  the  organic  scale.  Von  Baer's  definition  of,  186. 

Aeby,  on  the  difference  between  the  skulls  of  man  and  the 
quadrumana,  170. 

-^Jsthetic  faculty,  not  highly  developed  in  savages,  105. 

Affection,  maternal,  79;  manife.station  of,  by  animals,  79;  parental 
and  filial,  partly  the  result  of  natural  selection,  120;  mutual,  of 
birds,  467;  shown  by  birds  in  confinement,  for  certain  persons,  467. 

Africa,  probably  the  birthplace  of  man,  177;  South,  crossed  popu- 
lation of,  198.  South,  retention  of  color  by  the  Dutch  in,  219;  Soutli, 
proportion  of  the  sexes  in  the  butterflies  of,  283;  tattooing  practiced 
in,  654;  Northern,  coiffure  of  natives  of,  655. 

Agassiz  L.,  on  conscience  in  dogs,  117;  on  the  coincidence  of  the 
races  of  man  with  zoological  provinces,  193;  on  the  number  of 
species  of  man,  198;  on  the  courtship  of  the  land  snails,  297;  on  the 
brightness  of  the  colors  of  male  fishes  during  the  breeding-sea.son, 
385;  on  the  frontal  protuberance  of  the  males  of  OeophagiiH  and 
Ciclda,  385,  392;  male   fishes   hatching    ova  in  their  mouths,   391; 


716  INDEX. 

sexual  differences  in  color  of  cliromids,  392;  on  the  sliglit  sexual 
differences  of  the  South  Americans,  640;  on  the  tattooing  of  the 
Amazonian  Indians,  657. 

Age,  in  relation  to  the  transmission  of  characters  in  birds,  528; 
variation  in  accordance  with,  in  birds,  551. 

AgelcEus  phosniceus,  255,  472. 

Ageronia  feronia,  noise  produced  by,  349. 

Agrion,  dimorphism  in,  328,  329. 

Agrion  RambuHi,  sexes  of,  328. 

Agrionidae,  difference  in  the  sexes  of,  828. 

Agrotis  exclamationis,  358. 

Ague,  tertian,  dog  suffering  from,  8. 

Ainos,  hairiness  of  the,  639. 

Aitchison,  Mr.,  on  sheep,  279. 

A'ithurus  polytmus,  young  of,  555. 

Albino  birds,  476. 

Alca  tarda,  young  of,  553. 

Alces  palmata,  587. 

Alder  and  Hancock,  MM. ,  on  the  nudi-branch  mollusca,  298. 

Allen,  J.  A.,  vigor  of  birds  earliest  hatched,  240,  241;  effect  of 
difference  of  temperature,  light,  etc,  on  birds,  254,  colors  of  birds, 
480;  on  the  relative  size  of  the  sexes  of  Callorhinus  ursinus,  588;  on 
the  name  of  Otaria  juhata,  594;  on  the  pairing  of  seals,  596;  on 
sexual  differences  in  the  color  of  bats,  610;  Allen,  S.,  on  the  habits 
of  Hoplopterus,  414:  on  the  plumes  of  Herons,  444;  on  the  vernal 
moult  of  Herodias  bubulcus,  445. 

Alligator,  courtship  of  the  male,  250,  398;  roaring  of  the  male, 
646. 

Amadavat,  pugnacity  of  male,  416. 
Amadina  Lathami,  display  of  plumage  by  the  male,  456;  amadina 
castanotis,  display  of  plumage  by  the  male,  455. 

Amazons,  butterflies  of  the,  283;  fishes  of  the,  389. 

America,  variation  in  the  skulls  of  aborigines  of,  29;  wide  range 
of  aborigines  of,  193;  lice  of  the  natives  of,  193;  general  beardless- 
ness  of  the  natives  of,  639;  North,  butterflies  of,  283;  Indians  of, 
women  a  cause  of  strife  among  the,  640;  Indians  of,  their  notions  of 
female  beauty,  659,  662;  South,  character  of  the  natives  of,  191; 
population  of  parts  of,  197;  piles  of  stone  in,  204;  extinction  of  the 
fossil  horse  of,  218,  desert  birds  of,  558;  slight  sexual  difference  of 
the  aborigines  of,  640;  prevalence  of  infanticide  in,  675. 

American  languages,  often  highly  artificial,  103. 

Americans,  wide  geographical  range  of,  33;  native,  variability  of, 
198;  and  negroes,  difference  of,  224;  aversion  of,  to  hair  on  the  face, 
662. 

Ammophila,  on  the  jaws  of,  312. 

AjnmotraguH  tragelaphus,  hairy  forelegs  of,  606,  609. 

Amphibia,  affinity  of,  to  the  ganoid  fishes,  180;  vocal  organs  of 
the,  646. 

Amphibians,  187,  394;  breeding  while  immature,  551. 

A  7npMoxus,  181. 

Aiuphipoda,  males  sexually  mature  while  young,  552^ 

Amunoph  III,  negro  cliaracter  of  features  of,  192. 

Anal  appendages  of  insects,  313i 


INDEX.  un 

Analogous  variation  in  the  plumage  of  birds,  438. 

AndSy  525;  anas  a^uta,  male  plumage  of,  446;  anas  boschas,  male 
plumage  of,  446;  anas  histrionica,  552;  anas  punctata,  425. 

Anastomus  oscitans,  sexes  and  young  of,  553;  white  nuptial  plum- 
age of,  560. 

Anatidae,  voices  of,  425. 

Anax  Junius,  difiEerences  in  the  sexes  of,  328. 

Andaman  islanders,  susceptible  to  change  of  climate,  214. 

Anderson.  Dr..  on  the  tail  of  Macacus  hrunneus,  66;  the  Bufo 
sikimmensis,  396;  sounds  of  Echis  caHnata,  400. 

Andrmmfulca,  331. 

Anglo-Saxons,  estimation  of  the  beard  among  the,  663. 

Animals,  domesticated,  more  fertile  than  wild.  50;  cruelty  of 
savages  to,  133;  characters  common  to  man  and,  166;  domestic, 
change  of  breeds  of,  680. 

Annelida,  299;  colors  of,  299. 

Anobium  tesseilatum^  sounds  produced  by,  347. 

Anolis  cristatellus,  male,  crest  of,  401;  pugnacity  of  the  male,  401; 
throat-pouch  of,  402. 

Anser  canadensis,  473;  anser  cygnoides,  471;  knob  at  the  base  of 
the  beak  of,  484;  anser  hpperboreus,  whiteness  of,  560. 

Antelope,  prong-horned,  horns  of,  265. 

Antelopes,  generally  polygamous,  246;  horns  of,  265,  575;  canine 
teeth  of  some  male,  572;  use  of  horns  of,  580;  dorsel  crests  in,  606; 
dewlaps  of,  608;  winter  change  of  two  species  of,  619;  peculiar 
markings  of,  621. 

Antennae,  furnished  with  cushions  in  the  male  of  PentTie^  313. 

Anthidium  manicatum,  large  male  of.  316. 

Anthocharis  cardamines,  350,  354  ;  sexual  difference  of  color  in, 
364;  anthocharis  genutia,  ^^,  anthocharis  sar a,  354. 

Anthaphora  acervorum,  large  male  of,  316 ;  anthophora  retusa, 
difference  of  the  sexes  in,  331. 

Anthropidae,  173. 

Anthus,  molting  of,  444. 

Antics  of  birds,  431 . 

Antigua,  Dr.  Nicholson's  observations  on  yellow  fever  in,  222. 

Antiiocapra  americana,  horns  of,  265,  575,  578. 

AntUope  bezoartica,  horned  females  of,  575,  577,  578;  sexual  differ- 
ence in  the  color  of,  611:  antilope  Dm'cas  exichore,  575. 

AntUope  euchore,  horns  of,  580;  antilope  montana,  rudimentary 
canines  in  the  young  male  of,  586;  antilope  niger,  sing-sing,  cnama 
and  gorgon,  sexual  differences  in  the  colors  of,  612;  afitilope  areas, 
horns  of,  265;  antilope  saiga,  polygamous  habits  of,  246;  antilope 
strepsiceros,  horns  of,  265;  antilope  subgutturosa,  absence  of  suborbital 
pits  in,  604. 

Antipathy,  shown  by  birds  in  confinement,  to  certain  persons,  467. 

Ants,  167;  large  size  of  cerebral  ganglia  in,  60;  soldier,  large  jaws 
of,  70;  playing  together,  77;  memory  in,  83;  intercommunication  of, 
by  means  of  the  antennae,  101;  habits  of,  167  ;  difference  of  the 
sexes  in,  330;  recognition  of  each  other  bv,  after  separation,  330: 
white,  habits  of.  330. 

Anura,  395. 

Apatania  muliebris,  male  unknown,  287. 


718  INDEX, 

Apathus,  difference  of  the  sexes  in,  331. 

Apatura  IrU,  348,  350. 

Apes,  difference  of  the  young,  from  the  adult,  9;  semi-erect  atti- 
tude of  some,  58;  mastoid  processes  of,  59;  influences  of  the  jaw- 
muscles  on  the  physiognomy  of,  60;  female,  destitute  of  large 
canines,  71;  building  platforms,  93;  imitative  faculties  of,  146; 
anthropomorphous,  175;  probable  speedy  extermination  of  the,  177; 
Gratiolet  on  the  evolution  of,  202;  canine  teeth  of  male,  572; 
females  of  some,  less  hairy  beneath  than  the  males,  686;  long- 
armed,  their  mode  of  progression,  58. 

Aphasia,  Dr.  Bateman  on,  100. 

Apis  mellifica,  large  male  of,  316. 

Apollo,  Greek  statues  of,  663. 

Apoplexy  in  Cehus  Azarce,  7. 

Appendages,  anal,  of  insects,  313. 

Approbation,  influence  of  the  love  of,  124,  132,  148. 

Aprosmictus  scapulatus,  521. 

Apus,  proportion  of  sexes,  287. 

Aquatic  birds,  frequency  of  white  plumage  in,  561. 

Aquila  chrymetos,  463. 

Arab  women,  elaborate  and  peculiar  coiffure  of,  666. 

Arabs,  fertility  of  crosses  with  other  races,  195;  gashing  of  cheeks 
and  temples  among  the,  655. 

Arachnida,  307. 

Arakhan,  artificial  widening  of  the  forehead  by  the  natives 
of,  665. 

Arboricola,  young  of,  533. 

Archeopteryx,  180. 

Arctiidae,  coloration  of  the,  356. 

Ardea  asha,  rufescens  and  ccerulea,  change  of  color  in,  562,  563; 
ardea  cm'nlea,  breeding  in  immature  plumage,  552;  ardea  gulaiis, 
change  of  plumage  in,  563;  ardea  herodiaSy  love-gestures  of  the  male, 
431;  ardea  ludomciana,  age  of  mature  plumage  in,  551;  continued 
growth  of  crest  and  plumes  in  the  male  of,  552;  ardea  nycticorax, 
cries  of,  417. 

Ardeola,  young  of,  534. 

Ardetta,  changes  of  plumage  in,  524. 

Argenteuil,  24. 

Argus  pheasant,  435,  457,  526;  display  of  plumage  by  the  male, 
451;  ocellated  spots  of  the,  488;  gradation  of  characters  in  the,  494. 

Argyll,  Duke  of,  on  the  physical  weakness  of  man,  71;  the  fash- 
ioning of  implements  peculiar  to  man,  92;  on  the  contest  in  man 
between  right  and  wrong,  141;  on  the  primitive  civilization  of  man, 
162;  on  the  plumage  of  the  male  Argus  pheasant,  451;  on  Urosticte 
Benjamini,  503;  on  the  nests  of  birds,  515. 

Argynnis,  coloring  of  the  lower  surface  of,  356. 

Aricons  epitus,  sexual  differences  in  the  wings  of,  314. 

Aristocracy,  increased  beauty  of  the,  669. 

Arms,  proportions  of,  in  soldiers  and  sailors,  36;  direction  of  the 
hair  on  the,  177;  and  hands,  free  use  of,  indirectly  correlated  with 
diminution  of  canines,  60. 

Arrest  of  development,  40,  41. 

Arrow-heads,  stone,  general  resemblance  of,  203. 


INDEX.  719 

Arrows,  use  of,  203. 

Arteries,  variations  in  the  course  of  the,  30. 

Artery,  effect  of  tying,  upon  the  lateral  channels,  36. 

Arthropoda,  299. 

Arts  practiced  by  savages,  203. 

Ascension,  colored  incrustation  on  the  rocks  of,  298. 

Ascidia,  affinity  of  the  lancelet  to,  181;  tadpole-like  larvae  of,  181. 

Ascidians,  296;  bright  colors  of  some,  295. 

Asimis,  Asiatic  and  African  species  of,  626,  asinus  t(trdopvs,  626. 

Ass,  color- variations  of  the,  626. 

Aides,  effects  of  brandy  on  an,  8;  absence  of  the  thumb  in,  57; 
ateles  beelzebuth,  ears  of  16;  ateles  marginatiM,  color  of  the  ruff  of, 
613;  hair  on  the  head  of,  627. 

Ateuchtis  cicatricosuSy  habits  of,  340. 

Atetichus,  stridulation  of,  346. 

Athalia,  proportions  of  the  sexes  in,  286. 

Atrapus  pulsatorius,  330. 

Attention,  manifestations  of,  in  animals,  83. 

Audouin,  V.,  on  a  hvmenopterous  parasite  with  a  sedentary  male, 
251. 

Audubon,  J.  J.,  on  the  pinioned  goose,  119  ;  on  the  speculum  of 
MergiLS  eucuUatus,  267;  on  the  pugnacity  of  male  birds,  411,  414; 
on  courtship  of  Caprimulgus,  416;  on  Tetrao  cupido,  417;  on  Ardea 
nyctic&rax,  417;  on  Stumella  ludoviciana,  417;  on  the  vocal  organs 
of  Tetrao  cupido,  422;  on  the  drumming  of  the  male  Tetrao  umbel- 
Itis,  426;  on  sounds  produced  by  the  nightjar,  426,  427;  on  Ardea 
herodias  and  Cathartes  jota,  431,  432;  on  Mimus  polyglottus,  686;  on 
display  in  male  birds,  447;  on  the  spring  change  of  color  in  some 
finches,  446;  on  migration  of  mocking  thrushes,  467;  recognition  of 
a  dog  by  a  turkey,  468;  selection  of  mate  by  female  birds,  472;  on 
the  turkey,  468;  on  variation  in  the  male  scarlet  tanager,  481;  on  the 
musk-rat,  619;  on  the  habits  of  Pyranga  cestiva,  515;  on  local  differ- 
ences in  the  nests  of  the  same  species  of  birds,  519;  on  the  habits  of 
woodpeckers,  521  ;  on  BoiribycUla  carolinensis,  525  ;  on  young 
females  of  Pyranga  cestiva  accjuiring  male  characters,  525;  on  the 
immature  plumage  of  thrushes,  530;  on  the  immature  plumage  of 
birds,  530;  et  seq.,  on  birds  breeding  in  immature  plumage,  551;  on 
the  growth  of  the  crest  and  plumes  in  the  male  Ardea  ludoviciana, 
551 ;  on  the  change  of  color  in  some  species  of  Ardea,  562. 

Audubon  and  Bachman,  MM.,  on  squirrels  fighting,  570;  on  the 
Canadian  lynx,  594. 

Aughey,  Prof.,  on  rattlesnakes,  401. 

Austen,  N.  L.,  on   Anolis  cristatellus,  401. 

Australia,  not  the  birthplace  of  man,  176;  half-castes  killed  by  the 
natives  of,  194;  lice  of  the  natives  of,  193. 

Australia,  South,  variation  in  the  skulls  of  aborigines  of,  28. 

Australians,  color  of  new-born  children  of,  636;  relative  height  of 
the  sexes  of,  638;  women  a  cause  of  war  among  the.  640. 

Axis  deer,  sexual  difference  in  the  color  of  the,  612, 

Aymaras,  measurements  of  the,  39;  no  grey  hair  among  the,  637; 
hairlessness  of  the  face  in  the,  639;  long  hair  of  the,  662. 

Azara,  on  the  proportion  of  men  and  women  among  the  Guaranys, 
276;  on  Palamedea  cornuta,  412;  on  the  beards  of  the  Guaranys, 


720  INDEX. 

639;  on  strife  for  women  among  tlie  Guanas,  640  ;  on  infanticide, 
659,  675;  on  the  eradication  of  the  eyebrows  and  eyelashes  by  the 
Indians  of  Paraguay,  662;  on  polyandry  among  the  Guanas,  677;  celi- 
bacy unknown  among  the  savages  of  South  America,  678;  on  the 
freedom  of  divorce  among  the  Charruas,  683, 

Babbage,  C,  on  the  greater  proportion  of  illegitimate  female 
births,  276. 

Babirusa,  tusks  of  the,  592. 

Baboon,  revenge  in  a,  78;  rage  excited  in,  by  reading,  80;  mani- 
festation of  memory  by  a,  83;  employing  a  mat  for  shelter  against 
the  sun,  93;  protected  from  j)unishment  by  its  companions,  117; 
Cape,  mane  of  the  male,  594;  Hamadryas,  mane  of  the  male,  594. 

Baboon,  effects  of  intoxicating  liquors  on,  8;  ears  of,  17;  diversity 
of  the  mental  faculties  in,  30;  hands  of,  56;  habits  of,  57;  variability 
of  the  tail  in,  65;  manifestation  of  maternal  affection  by,  79;  using 
stones  and  sticks  as  weapons,  92  ;  co-operation  of,  115  ;  silence  of, 
on  plundering  expeditions,  118;  apparent  polygamy  of,  245;  polyga- 
mous and  social  habits  of,  674. 

Baboons,  courtship  of,  710. 

Bachman,  Dr.,  on  the  fertility  of  mulattoes,  194. 

Baer,  K.  E.  von,  on  embryonic  development,  9;  definition  of 
advancement  in  the  organic  scale,  186. 

Bagehot,  W.,  on  the  social  virtues  among  primitive  men,  132  ; 
slavery  formerly  beneficial,  133;  on  the  value  of  obedience,  147;  on 
human  progress,  150;  on  the  persistence  of  savage  tribes  in  classical 
times,  208. 

Bailey,  E.  M.,  on  the  mode  of  fighting  of  the  Italian  buffalo,  580; 
on  the  fighting  of  stags,  582. 

Bain,  A.,  on  the  sense  of  duty,  111;  aid  springing  from  sympathy, 
116;  on  the  basis  of  sympathy,  120;  on  the  love  of  approbation,  etc., 
124;  on  the  idea  of  beauty,  667. 

Baird,  W.,  on  a  difference  in  color  between  the  males  and  females 
of  some  Entozoa,  294. 

Baker,  Mr.,  observation  on  the  proportion  of  the  sexes  in  pheas- 
ant-chicks, 280;  Sir  S.,  on  the  fondness  of  the  Arabs  for  discordant 
music,  431;  on  sexual  difference  in  the  colors  of  an  antelope,  612; 
on  the  elephant  and  rhinoceros  attacking  white  or  grey  horses,  617; 
on  the  disfigurements  practiced  by  the  negroes,  617;  on  the  gashing 
of  the  cheeks  and  temples  practiced  in  Arab  countries,  655;  on  the 
coiffure  of  the  North  Africans,  656;  on  the  perforation  of  the  lower 
lip  by  the  women  of  Latooka  656;  on  the  distinctive  characters  of 
the  coiffure  of  central  African  tribes,  656;  on  the  coiffure  of  Arab 
women,  666. 

"  Balz  "  of  the  black  cock,  412,  460. 

Bantam,  Sebright,  239,  270. 

Banteng,  horns  of,  576  ;  sexual  differences  in  the  colors  of  the, 
612. 

Banyal,  color  of  the,  661. 

Barbarism,  primitive,  of  civilized  nations,  162. 

Barbs,  filamentous,  of  the  feathers,  in  certain  birds,  437,  489. 

Barr,  Mr.,  on  sexual  preference  in  dogs,  598. 

Barrage,  F.,  on  the  Simian  resemblances  of  man,  3. 

jBarrington,  Daines,  on  the  language  of  birds,  97;  on  the  duckling 


INDEX,  721 

of  the  hen,  418;  on  the  object  of  the  song  of  birds,  419;  on  the  sing- 
ing of  female  birds,  420;  on  birds  acquiring  the  songs  of  other 
birds,  420;  on  the  muscles  of  the  larynx  in  song  birds,  421;  on  the 
want  of  the  power  of  song  by  female  birds,  513. 

Barrow,  on  the  widow- bird,  457. 

Bartels,  Dr.,  supernumerary  mammae  in  men,  42. 

Bartlett,  A.  D.,  period  of  hatching  of  bird's  eggs,  187;  on  the 
tragopan,  249;  on  the  development  of  the  spurs  in  CrossoptUon 
auritum,  267;  on  the  fighting  of  the  males  of  Plectropterus  gamben 
sis,  414;  on  the  knot,  444;  on  display  in  male  birds,  M7;  on  the  dis- 
play of  plumage  by  the  male  Polyplectron,  449  ;  on  CrossoptUon 
auritum  and  P/uisianus  WaUiehii,  454;  on  the  habits  of  Lophophorus, 
477;  on  the  color  of  the  mouth  in  Buceros  bicornis,  484;  on  the  incu- 
bation of  the  cassowary,  544;  on  the  Cape  Buffalo,  580;  on  the  use 
of  the  horns  of  antelopes,  580;  on  the  fighting  of  male  wart-hogs, 
593;  on  Ammotrag^is  tragekiphus,  606;  on  the  colors  of  Cercopithecits 
cephus,  614;  on  the  colors  of  the  faces  of  monkeys,  629;  on  the 
naked  surfaces  of  monkeys,  686. 

Bartlett,  on  courting  of  Argus  pheasant,  454. 

Bartram,  on  the  courtship  of  the  male  allegator,  398. 

Basque  language,  highly  artificial,  102. 

Bate,  C,  S.,  on  the  superior  activity  of  male  Crustacea,  250;  on  the 
proportions  of  the  sexes  in  crabs,  2^;  on  the  chelae  of  Crustacea,  301; 
on  the  relative  size  of  the  sexes  in  Crustacea,  302;  on  the  colors  of 
Crustacea,  306. 

Bateman,  Dr.,  tendency  to  imitation  in  certain  diseased  states,  82; 
on  Aphasia,  100. 

Bates,  H.  W.,  on  variations  in  the  form  of  the  head  of  Amazonian 
Indians,  32;  on  the  proportion  of  sexes  among  Amazonian  butter- 
flies, 283;  on  sexual  differences  in  the  wings  of  butterflies,  314;  on 
the  field-cricket,  321;  on  Pyrodes  pulcJierrimus,  333;  on  the  horns  of 
Lamellicorn  beetles,  334,  336;  on  the  colors  of  Epicaliw,  etc.,  350;  on 
the  coloration  of  tropical  butterflies,  352:  on  the  variability  of  Papilio 
Sesostris  and  ChUdrena,  362;  on  male  and  female  butterflies  inhabit- 
ing different  stations,  364;  on  mimicry,  366;  on  the  caterpillar  of  a 
Sphinx,  369;  on  the  vocal  organs  of  the  umbrella-bird,  423;  on  the 
toucans,  560;  on  Brachyurus  caZmis,  629. 

Batokas,  knocking  out  two  upper  incisors,  656. 

Batrachia,  395;  eagerness  of  male,  250. 

Bats,  scent-glands,  604;  sexual  differences  in  the  color  of,  610;  fur 
of  male  frugivorous,  610. 

Battle,  law  of,  163;  among  beetles,  339;  among  birds,  408;  among 
mammals,  570  et  seq.j  in  man,  640. 

Beak,  sexual  difference  in  the  forms  of  the,  408;  in  the  color  of 
the,  435. 

Beaks,  of  birds,  bright  colors  of,  559. 

Beard,  development  of,  in  man,  635;  analogy  of  the,  in  man  and 
the  quadrumana,  636;  variation  of  the  development  of  the,  in  dif- 
ferent races  of  men,  637;  estimation  of,  among  bearded  nations,  663; 
probable  origin  of  the,  688;  in  monkeys,  171;  of  mammals,  607. 

Beautiful,  taste  for  the,  in  birds,  466;  in  the  quadrumana,  617. 

Beauty,  s*^nse  of,  in  animals,  104;  appreciation  of,  by  birds,  469; 
influence  of ,  654,  657;  variability  of  the  standard  of,  681;  sense  of. 
guflSciently  permanent  for  action  of  sexual  selection,  563,  712. 


72»  INDEX, 

Beavan,  Lieut.,  on  the  development  of  the  liorns  in  Cervus  Kldi,  205; 

Keaver,  instinct  and  intelligence  of  the,  75,  77;  voice  of  the,  602. 
oastoreum  of  the,  604. 

Beavers,  battles  of  male,  570. 

Bechstein,  on  female  birds  choosing  the  best  singers  among  tlio 
males,  418;  on  rivalry  in  song-birds,  419;  on  the  singing  of  female 
birds,  420;  on  binls  acquiring  the  songs  of  other  birds,  420;  on  pair- 
ing the  canary  and  siskin,  472;  on  a  sub- variety  of  the  monk  pigeon, 
472;  on  spurred  hens,  511. 

Beddoe,  Dr. ,  on  causes  of  difference  in  stature,  35. 

Bee  eater,  421. 

Bees,  113;  pollen- baskets  and  stings  of,  70;  destruction  of  drones 
and  queens  by,  120;  female,  secondary  sexual  characters  of,  235; 
proportion  of  sexes,  286;  difference  of  the  sexes  in  color  and  sexual 
selection,  331. 

Beetle,  luminous  larva  of  a,  314. 

Beetles,  333;  size  of  the  cerebral  ganglia  in,  61;  dilatation  of  the 
fore  tarsi  in  male,  312;  blind,  333;  stridulation  of,  341. 

Belgium,  ancient  inhabitants  of,  207. 

Bell,  Sir  C,  on  the  emotional  muscles  in  man,  4;  "snarling  mus- 
cles," 46;  on  the  hand,  57;  Bell,  T.,  on  the  numerical  proportion  of 
the  sexes  in  moles,  279;  on  the  newts,  394;  on  the  croaking  of  the 
frog,  395;  on  the  difference  in  the  coloration  of  the  sexes  in  Zootoca 
vivipara,  405;  on  moles  fighting,  570. 

Bell- bird,  sexual  difference  in  the  color  of  the,  440. 

Bell-birds,  colors  of,  560. 

Belt,  Mr.,  on  the  nakedness  of  tropical  mankind,  64;  on  a  spider- 
monkey  and  eagle,  115;  habits  of  ants,  168;  Lampyridse  distasteful 
to  mammals,  314;  mimicry  of  Leptalides,  368;  colors  of  Nicaraguan 
frogs,  396;  display  of  humming-birds,  503;  on  the  toucans,  560;  pro- 
tective coloring  of  skunk,  621. 

Benevolence  manifested  by  birds,  467. 

Bennett,  A.  W.,  attachment  of  mated  birds,  466;  on  the  habits  of 
Drommus  irroratus,  545;  Bennett,  D.,  on  birds  of  paradise,  449. 

Berbers,  fertility  of  crosses  with  other  races,  195. 

Berniela  antarctica,  colors  of,  560. 

Bernicle  gander  pairing  with  a  Canada  goose,  471. 

Bert,  M.,  crustaceans  distinguish  colors,  306. 

Bettoni,  E.,  on  local  differences  in  the  nests  of  Italian  birds,  519. 

Beyle,  M.,  see  Bombet. 

Bhoteas,  color  of  the  beard  in,  637. 

BhHnga,  disciform  tail-feathers  of,  445. 

Bianconi,  Prof.,  on  structures  as  explained  through  mechanical 
principles,  27. 

Bibio,  sexual  differences  in  the  genus,  317. 

Bichat,  on  beauty,  667. 

Bickes,  proportion  of  sexes  in  man,  274. 

Bile,  colored  in  many  animals,  296. 

Bimana,  170. 

Birds,  imitations  of  the  songs  of  other  birds  by,  82;  dreaming,  84; 
killed  by  telegraph  wires,  90;  language  of,  97;  sense  of  beauty  in, 
104;  pleasure  of,  in  incubation,  119;  male,  incubation  by,  185;' and 
reptiles,  alliance  of,  187;  sexual  differences  in  the  beak  of  some,  236; 


INDEX.  723 

migratory,  arrival  of  the  male  before  tLe  female,  241 ;  apparent  rela- 
tion between  polygamy  aud  marked  sexual  differences  in,  248; 
monogamous,  becoming  polygamous  under  domesticatiottj  249; 
eagerness  of  male  in  pursuit  of  the  female,  260;  wild,  numerical 
proportion  of  the  sexes  in,  280;  secondary  sexual  characters  of,  407; 
difference  of  size  in  the  sexes  of,  411;  fights  of  male,  witnessed  by 
females,  414;  display  of  male,  to  captivate  the  females,  416;  close 
attention  of,  to  the  songs  of  others,  418;  acquiring  the  song  of  their 
foster  parents,  420;  brilliant,  rarely  good  songsters,  421;  love-antics 
and  dances  of,  431;  coloration  of,  438  et  seq.;  moulting  of,  442  e^  seq.; 
unpaired,  462;  male,  singing  out  of  season,  465;  mutual  affection  of, 
466;  in  confinement,  distinguish  persons,  467;  hybrid,  production  of, 
470;  Albino,  476;  Euroj>ean.  number  of  species  of,  479;  variability 
of,  479;  geographical  distribution  of  coloring,  480;  gradation  of 
secondary  sexual  characters  in,  488;  obscurely  colored,  building  con- 
cealed nests,  516;  young  female,  acquiring  male  characters,  525; 
breeding  in  immature  plumage,  551;  moulting  of,  551;  aquatic,  fre- 
quency of  white  plumage  in,  561;  vocal  courtship  of,  646;  naked 
skin  of  the  head  and  neck  in,  686. 

Birgus  latro,  habits  of,  305. 

Birkbeck,  Mr.,  on  the  finding  of  new  mates  by  golden  eagles,  463. 

Birthplace  of  man,  176. 

Births,  numerical  proportions  of  the  sexes  in,  in  animals  and 
man,  243,  244;  male  and  female,  numerical  proportion  of,  in  England, 
274. 

Bischoff,  Prof.,  on  the  agreement  between  the  brains  of  man  and 
of  the  orang.  6;  figure  of  the  embryo  of  the  dog,  11;  on  the  convo- 
lutions of  the  brain  in  the  human  fetus,  10;  on  the  difference 
between  the  skulls  of  man  and  the  quadrumana,  170;  resemblance 
between  the  ape's  and  man's,  227. 

Bishop,  J.,  on  the  vocal  organs  of  frogs,  397;  on  the  vocal  organs 
of  corvine  birds,  421;  on  the  trachea  of  the  Merganser,  425. 

Bison,  American,  co-operation  of,  115;  mane  of  the  male,  594. 

Bitterns,  dwarf,  coloration  of  the  sexes  of,  524. 

Biziura  lobata,  musky  odor  of  the  male,  407;  large  size  of  male, 
411. 

Blackbird,  sexual  differences  in  the,  248;  proportion  of  the  sexes 
in  the,  281 ;  acquisition  of  a  song  by,  421 ;  color  of  the  beak  in  the 
sexes  of  the,  435,  559;  pairing  with  a  thrush,  470;  colors  and  nidifi- 
cation  of  the,  517;  young  of  the,  554,  555;  sexual  difference  in  colora- 
tion of  the,  559, 

Black-buck,  Indian,  sexual  difference  in  the  color  of  the,  612. 

Blackcap,  arrival  of  the  male,  before  the  female,  240;  young  of 
the,  554. 

Black-cock,  polygamous,  248;  proportion  of  the  sexes  in  the,  279; 
pugnacity  and  love-dance  of  the,  412;  call  of  the,  425  ;  moulting  of 
the,  444;  duration  of  the  courtship  of  the,  460  ;  and  pheasant, 
hybrids  of,  125;  sexual  difference  in  coloration  of  the,  559;  crimson 
eye-cere  of  the,  559. 

Black-grouse,  characters  of  young,  530,  537. 

Blacklock,  Dr.,  on  music,  653. 

Blackwall,  J.,  on  the  speaking  of  the  magpie,  101;  on  the  deser- 
tion of  their  young  by  swallows,  122;  on  the  superior  activity  of 


724  INDEX. 

male  spiders,  250;  on  tlie  proportion  of  the  sexes  in  spiders,  287;  on 
sexual  variation  of  color  in  spiders,  307;  on  male  spiders,  307. 

Bladder- nose  Seal,  hood  of  the,  603. 

Blaine,  on  the  affections  of  dogs,  597. 

Blair,  Dr. ,  on  the  relative  liability  of  Europeans  to  yellow  fever, 
221. 

Blake,  C.  C. ,  on  the  jaw  from  La  Naulette,  46. 

Blakiston,  Capt.,  on  the  American  snipe,  428;  on  the  dances  of 
Tetrao  phasianellus,  431. 

Blasius,  Dr.,  on  the  species  of  European  birds,  480. 

Bledius  taurus,  hornlike  processes  of  male,  338. 

Bleeding,  tendency  to  profuse,  268. 

Blenkiron,  Mr.,  on  sexual  preference  in  horses,  598. 

Blennies,  crest  developed  on  the  head  of  male,  during  the  breeding 
season,  385. 

Blethisa  multipunctata,  stridulation  of,  343. 

Bloch,  on  the  proportions  of  the  sexes  in  fishes,  281. 

Blood,  arterial,  red  color  of,  296;  pheasant,  number  of  spurs  in, 
413. 

Blow-fly,  sounds  made  by,  318. 

Bluebreast,  red-throated,  sexual  differences  of  the,  537. 

Blumenbach,  on  Man,  32;  on  the  large  size  of  the  nasal  cavities  in 
American  aborigines,  38;  on  the  position  of  man,  170;  on  the  number 
of  species  of  man,  199. 

Blyth,  E.,  on  the  structure  of  the  hand  in  the  species  of  Ilyldbates, 
57;  observations  on  Indian  crows,  116;  on  the  development  of  the 
horns  in  the  Koodoo  and  Eland  antelopes,  265;  on  the  pugnacity  of 
the  males  of  Oallicrex  cristatua,  409;  on  the  presence  of  spurs  in  the 
female  Euplocamus  erythrophthalmus,  413;  on  the  pugnacity  of  the 
amadavat,  415;  on  the  spoonbill,  425;  on  the  moulting  of  Anthus, 
444;  on  the  moulting  of  bustards,  plovers,  and  Gallus  bankiva,  445; 
on  the  Indian  honey-buzzard,  481  ;  on  sexual  differences  in  the 
the  color  of  the  eyes  of  hornbills,  483;  on  Oriolus  melanocephalus, 
524;  on  Paloeornis  javanicus,  525;  on  the  genus  Ardetta,  524;  on  the 
peregrine  falcon,  525;  on  young  female  birds  acquiring  male  charac- 
ters, 524;  on  the  immature  plumage  of  birds,  529;  on  representative 
species  of  birds,  533;  on  the  young  of  Turnia',  543;  on  anomalous 
young  of  Lanius  rnfus  and  Colymhus  glacialis,  550;  on  the  sexes 
and  young  of  the  sparrows,  550;  on  dimorphism  in  some  herons,  552; 
on  the  ascertainment  of  the  sex  of  nestling  bullfinches  by  pulling 
out  breast  feathers,  551;  on  orioles  breeding  in  immature  plumage, 
552;  on  the  sexes  and  young  of  Buphus  and  Anastomus,  553;  on  the 
young  of  the  blackcap  and  l)lackbird,  554,  555;  on  the  young  of  the 
stonechat,  555;  on  the  white  plumage  of  Anastomus,  561;  on  the 
horns  of  Bovine  animals,  575;  on  the  horns  of  Antilope  bezoartica, 
575,  577;  on  the  mode  of  fighting  of  Ovis  ci/cloceros,  579;  on  the  voice 
of  the  Gibbons,  602;  on  the  crest  of  the  male  wild  goat,  606;  on  the 
colors  of  PoTtax picta,  611;  on  the  colors  of  Antilope  bezoartica,  612; 
on  the  color  of  the  Axis  deer,  613;  on  sexual  difference  of  color  in 
Hylobates  hoolock,  613  ;  on  the  hog-deer,  624  ;  on  the  beard  and 
whiskers  in  a  monkey  becoming  white  with  age,  637. 

Boar,  wild,  polygamous  in  India,  246;  use  of  the  tusks  by  the, 
585;  fighting  of,  591. 


Index.  725 

Boardman,  Ml*.,  Albino  birds  in  U.  S.,  476. 

Boitard  and  Corbie,  MM.,  on  the  transmission  of  sexual  peculiari- 
ties in  pigeons,  261;  on  the  antipathy  shown  by  some  female  pigeons 
to  certain  males,  474. 

Bold,  Mr.,  on  the  singing  of  a  sterile  hybrid  canary,  419. 

Bombet,  on  the  variability  of  the  standard  of  beauty  in  Europe, 
681. 

Bombus,  difference  of  the  sexes  in.  331. 

Bombycidse,  coloration  of,  355;  pairing  of  the,  360,  colors  of,  361. 

BombyctUa  carolinends,  red  appendages  of,  525. 

Bombyx  cynthia,  315;  proportion  of  the  sexes  in,  282,  285;  pairing 
of,  360;  hombyx  mori,  difference  of  size  of  the  male  and  female 
cocoons  of,  315;  pairing  of,  360;  bombyx  pemyi,  proportion  of  sexes 
of,  285;  bombyx  yamamai,  315;  M.  Personat  on,  283;  proportion  of 
sexes  of,  285. 

Bonaparte,  C.  L.,  on  the  call-notes  of  the  wild  turkey,  425. 

Bond,  F.,  on  the  finding  of  new  mates  by  crows,  463. 

Bone,  implements  of,  skill  displayed  in  making,  55. 

Boner,  C,  on  the  transfer  of  male  characters  to  an  old  female 
chamois,  574;  on  the  habits  of  stags,  587;  on  the  pairing  of  red  deer, 
595. 

Bones,  increase  of,  in  length  and  thickness,  when  carrying  a 
greater  weight,  36. 

Bonizzi,  P.,  difference  of  color  in  sexes  of  pigeons,  261. 

Bonnet  monkey,  171, 

Bonwick,  J.,  extinction  of  Tasmanians,  209. 

Boomerang,  164. 

Boreus  hyemalis,  scarcity  of  the  male,  287, 

Bory  St.  Vincent,  on  the  number  of  species  of  man,  199;  on  the 
colors  of  Labrus  pato,  388. 

Bos  etruscus,  576;  bos  gaurus,  horns  of,  576;  bos  moschatus,  604; 
bos  piimigenius,  571;  bos  sondaicus,\ioTnsoi,  576;  colors  of,  612. 

Botocudos,  163;  mode  of  life  of,  224;  disfigurement  of  the  ears 
and  lower  lip  of  the,  656, 

Boucher  de  Perthes.  J.  C.  de,  on  the  antiquity  of  man ,  2, 

Bourbon,  proportion  of  the  sexes  in  a  species  of  Papilio  from,  283. 

Bourien,  on  the  marriage  customs  of  the  savages  of  the  Malay 
Archipelago,  683. 

Bovidae,  dewlaps  of,  608. 

Bower-birds,  461;  habits  of  the,  432;  ornamented  playing-places 
of,  104,  469. 

Bows,  use  of,  203. 

Brachycephalic  structure,  i)ossible  explanation  of,  63. 

Brachyura,  304. 

Brachyurus  calvns,  scarlet  face  of,  629. 

Bradley,  Mr.,  abductor  ossis  metatarsi  quinti  in  man,  47. 

Brain,  of  man,  agreement  of  the,  with  that  of  lower  animals,  6; 
convolutions  of,  in  the  human  fetus,  10;  influence  of  development 
of  mental  faculties  upon  the  size  of  the,  60;  influence  of  the  devel- 
opment of,  on  the  spinal  column  and  skull,  62;  larger  in  some  exist- 
ing mammals  than  in  their  tertiary  prototyi)es,  91;  relation  of  the 
development  of  the,  to  the  jjrogress  of  language,  99;  disease  of  the, 
affecting  speech,  99;  difference  in  the  convolutions  of,  in  different 


726  INDEX. 

races  of  men,  191;  supplement  on,  by  Prof.  Huxley,  227;  develop- 
ment of  the  gyri  and  sulci,  231. 

Brakenridge,  Dr.,  on  the  influence  of  climate,  36. 

Brandt,  A.,  on  hairy  men,  21. 

Braubach,  Prof.,  on  the  quasi -religious  feeling  of  a  dog  toward 
his  master,  108;  on  the  self-restraint  of  dogs,  117. 

Brauer,  F. ,  on  dimorphism  in  Neurothemis,  329. 

Brazil,  skulls  found  in  caves  of,  192;  population  of,  197;  compres- 
sion of  the  nose  by  the  natives  of,  665. 

Break  between  man  and  the  apes,  177. 

Bream,  proportion  of  the  sexes  in  the,  282. 

Breeding,  age  of,  in  birds,  552;  breeding  season,  sexual  charactettJ 
making  their  appearance  in  the,  in  birds,  443. 

Brehm,  -on  the  effects  of  intoxicating  liquors  on  monkeys,  8;  on 
the  recognition  of  women  by  male  Cynocephali,  8;  on  the  diversity  of 
the  mental  faculties  of  monkeys,  31;  on  the  habits  of  baboons,  57; 
on  revenge  taken  by  monkeys,  78;  on  manifestations  of  maternal 
affection  by  monkeys  and  baboons,  79;  on  the  instinctive  dread  of 
monkeys  for  serpents,  80;  on  the  use  of  stones  as  missils  by  baboons, 
92;  on  a  baboon  using  a  mat  for  shelter  from  the  sun,  93;  on  the 
signal-cries  of  monkeys,  98;  on  sentinels  posted  by  monkeys,  114;  on 
co-operation  of  animals,  114;  on  an  eagle  attacking  a  young  Cerco- 
pithfcus,  114;  on  baboons  in  confinement  protecting  one  of  their 
number  from  punishment,  117;  on  the  habits  of  baboons  when 
plundering,  108;  on  polygamy  in  Cynocephalus  and  Cebus,  246;  on 
the  numerical  proportion  of  the  sexes  in  birds,  280;  on  the  love- 
dance  of  the  blackcock,  412;  Palamedea  cornuta,  414;  on  the  habits 
of  the  black-grouse,  416;  on  sounds  produced  by  birds  of  paradise, 
427;  on  assemblages  of  grouse,  460;  on  the  finding  of  new  mates  by 
birds,  464;  on  the  fighting  of  wild  boars,  591;  on  sexual  differences 
in  Mycetes,  613;  on  the  habits  of  Cynocephalus  hamadryas,  674. 

Brent,  Mr.,  on  the  courtship  of  fowls,  473. 

Breslau,  numerical  proportion  of  male  and  female  births  in,  275. 

Bridgman,  Laura,  99. 

Brimstone  butterfly,  354;  sexual  difference  of  color  in  the,  365. 

British,  ancient,  tattooing  practiced  by,  655. 

Broca,  Prof.,  on  the  occurrence  of  the  supra-condyloid  foramen  in 
the  human  humerus,  24;  anthropomorphous  apes  more  bipedal  than 
quadrupedal,  59;  on  the  capacity  of  Parisian  skulls  at  different 
periods,  61;  comparison  of  modern  and  mediaeval  skulls,  61;  on  ts  ils 
of  quadrupeds,  65;  on  the  influence  of  natural  selection,  68;  on 
hybridity  in  man,  194;  on  human  remains  from  Les  Eyzies,  207;  on 
the  cause  of  the  difference  between  Europeans  and  Hindoos,  218. 

Brodie,  Sir  B.,  on  the  origin  of  the  moral  sense  in  man.  111. 

Bronn,  H.  G.,  on  the  copulation  of  insects  of  distinct  species,  312. 

Bronze  period,  men  of,  in  Europe,  145. 

Brown,  R.,  sentinels  of  seals  generally  females,  114;  on  the  bat- 
tles of  seals,  571;  on  the  narwhal,  572;  on  the  occasional  absence  of 
the  tusks  in  the  female  walrus,  572;  on  the  bladder-nose  seal,  603;  on 
the  colors  of  the  sexes  in  Phoca  OrceJilandica,  611;  on  the  apprecia- 
tion of  music  by  seals,  649;  on  plants  used  as  love-philters,  by  North 
American  women,  659. 

Browne,  Dr.  Crichton,  injury  to  infants  during  parturition,  276. 


INDEX.  727 

Brown-Sequard,  Dr.,  on  the  inheritance  of  the  effects  of  opera- 
tions by  guinea-pigs,  67,  689. 

Bruce,  on  the  use  of  the  elephant's  tusks,  578. 

Brulerie,  P.  de  la,  on  the  habits  of  Ateuchus  cicatricoms,  340;  on 
the  stridulation  of  Ateuchus,  346. 

Brilnnich,  on  the  pied  ravens  of  the  Feroe  Islands,  482. 

Bryant,  Dr.,  preference  of  tame  pigeon  for  wild  mate,  475;  Bry- 
ant, Capt. ,  on  the  courtship  of  CaUorhin  us  ursinus,  596. 

Bubas  bison,  thoracic  projection  of,  337. 

Bubulus  caffer,  use  of  horns,  580. 

Bucephalus  capensis,  difference  of  the  sexes  of,  in  color,  398. 

Buceros,  nidification  and  incubation  of,  516 ;  huceros  bicornis, 
sexual  differences  in  the  coloring  of  the  casque,  beak,  and  mouth  in, 
484;  buceros  corrugatus,  sexual  differences  in  the  beak,  435. 

Biichner,  L.,  on  the  origin  of  man,  3;  on  the  use  of  the  human 
foot  as  a  prehensile  organ,  58;  on  the  mode  of  progession  of  the 
apes,  58;  on  want  of  self-consciousness,  etc.,  in  savages,  94. 

Bucholz,  Dr. ,  quarrels  of  chamaeleons,  405. 

Buckinghamshire,  numerical  proportion  of  male  and  female  births 
in,  274. 

Buckland,  F.,  on  the  numerical  proportion  of  the  sexes  in  rats, 
279;  on  the  proportion  of  the  sexes  in  the  trout,  282;  on  ChinuBra 
monMrosa,  385. 

Buckland,  W.,  on  the  complexity  of  crinoids,  103. 

Buckler,  W.,  proportion  of  sexes  of  Lepidoptera  reared  by,  285. 

Bucorax  abyssinicus,  inflation  of  the  neck- wattle  of  the  male 
during  courtship,  435. 

Budytes  Rail,  240. 

Buffalo,  Cape,  580;  Indian,  horns  of  the,  576;  Italian,  mode  of 
fighting  of  the,  580. 

Buffon,  on  the  number  of  species  of  man,  199. 

Bufo  sikimmensis,  396. 

Bugs,  318. 

Buist,  R.,  on  the  proportion  of  the  sexes  in  salmon,  281;  on  the 
pugnacity  of  the  male  salmon,  377. 

Bulbul,  pugnacity  of  the  male,  409;  display  of  under  tail-coverts 
by  the  male,  456. 

Bull,  mode  of  fighting  of  the,  579;  curled  frontal  hair  of  the,  608. 

Buller,  Dr.,  on  the  Huia,  236;  the  attachment  of  bird3,  466. 

Bullfinch,  sexual  differences  in  the,  248 ;  piping,  418;  female, 
singing  of  the,  420;  courtship  of  the,  455;  widowed,  finding  a  new 
mate,  464:  attacking  a  reed-bunting,  468;  nestling,  sex  ascertained 
by  pulling  out  breast  feathers,  551. 

Bullfinches,  distinguishing  persons,  467;  rivalry  of  female,  477. 

Bulls,  two  young,  attacking  an  old  one,  115;  wild,  battles  of.  571. 

Bull-trout,  male,  coloring  of,  during  the  breeding-season,  386. 

Bunting,  reed,  head  feathers  of  the  male,  455;  attacked  by  a  bull- 
finch, 468. 

Buntings,  characters  of  young,  529. 

Buphus  coromandus,  sexes  and  young  of,  553;  change  of  color  in, 
563. 

Burchell,  Dr.,  on  the  zebra.  623;  on  the  extravagance  of  a  Bush- 
woman  in  adorning  herself,   658 ;   celibacy   unknown    among  the 


728  INDEX. 

savages  of  South  Africa,  678;  on  the  marriage-customs  of  the  Bush- 
women,  684. 

Burke,  on  the  number  of  species  of  man,  199. 

Burmese,  color  of  the  beard  in,  637. 

Burton,  Capt.,  on  negro  ideas  of  female  beauty,  660;  on  a  universal 
ideal  of  beauty,  664. 

Bushmen,  72;  marriage  among,  684. 

Bush  woman,  extravagant  ornamentation  of  a,  658. 

Bush  women,  hair  of,  191 ;  marriage-customs  of,  684. 

Bustard,  throat-pouch  of  the  male,  423;  humming  noise  produced 
by  a  male,  429;  Indian,  ear-tufts  of,  436. 

Bustards,  occurrence  of  sexual  differences  and  of  polygamy  among 
the,  248;  love-gestures  of  the  male,  432;  double  moult  in,  443,  444. 

Butler,  A.  G.,  on  sexual  differences  in  the  wings  of  Aricoin,8  epitus, 
314;  courtship,  of  butterflies,  348;  on  the  coloring  of  the  sexes  in 
species  of  Thecla,  351;  on  the  resemblance  of  Iphias  glaucippe  to  & 
leaf,  354;  on  the  rejection  of  certain  moths  and  caterpillars  by  lizards 
and  frogs,  370. 

Butterfly,  noise  produced  by  a,  349;  Emperor,  348,  350;  meadow 
brown,  instability  of  the  oscellated  spots  of,  486. 

Butterflies,  proportion  of  the  sexes  in,  283;  forelegs  atrophied  in 
some  males,  314;  sexual  difference  in  the  neuration  of  the  wings  of, 
314;  pugnacity  of  'male.  348;  protective  resemblances  of  the  lower 
surface  of,  353;  display  of  the  wings  by,  356;  white,  alighting  upon 
bits  of  paper,  359;  attracted  by  a  dead  specimen  of  the  same  species, 
360;  courtship  of,  360;  male  and  female  inhabiting  different  stations, 
364. 

Buxton,  C,  observations  on  macaws,  115;  on  an  instance  of  benev- 
olence in  a  parrot,  467. 

Buzzard,  Indian  honey,  variation  the  crest  of,  481. 

Cabbage  butterflies,  354. 

Cachalot,  large  head  of  the  male,  573. 

Cadences,  musical  perception  of,  by  animals,  648. 

Caecum,  22;  large,  in  the  early  progenitors  of  man,  182. 

Cairina  moschata,  pugnacity  of  the  male,  411. 

Calif ornian  Indians,  decrease  of,  291. 

Callianassa,  chelae  of,  figured,  302. 

CaUidryas,  colors  of  sexes,  361 . 

Callionymus  lyra,  characters  of  the  male,  381. 

Callorhinus  ur sinus,  relative  size  of  the  sexes  of,  588;  courtship 
of,  596. 

Calotes  maria,  406;  Calotes  nigrilabris,  sexual  difference  in  the 
color  of,  405. 

Cambridge,  O.  Pickard,  on  the  sexes  of  spiders,  287;  on  the  size  of 
male  Nephila,  309. 

Camel,  canine  teeth  of  male,  572,  586. 

Campbell,  J.,  on  the  Indian  elephant,  246;  on  the  proportion  of 
male  and  female  births  in  the  harems  of  Siam,  277. 

Campylojyterus  hemileueurus,  281. 

Canaries  distingushing  persons,  467. 

Canary,  polygamy  of  the,  249;  change  of  plumage  in,  after  moult- 
ing, 269;  female,  selecting  the  best  singing  male,  418;  sterile  hybrid, 
singing  of  a,  419;  female,  singing  of  the,  420;  selecting  a  greenfinch, 
472;  and  siskin,  pairing  of,  472. 


INDEX.  729 

Cancer  pagurus,  301. 

C'auestrini,  U.,  on  rudimentary  cliaracters  and  the  origin  of 
man,  8;  on  rudimentary  characters,  12;  on  the  movement  of  the  ear 
in  man,  15;  on  the  variability  of  the  vermiform  appendage  in  man, 
23;  on  the  abnormal  division  of  the  malar  bone  in  man,  44;  on 
abnormal  conditions  of  the  human  uterus,  44;  on  the  persistence  of 
the  frontal  suture  in  man,  44;  on  the  proportion  of  the  sexes  in  silk- 
moths,  282,  284;  secondary  sexual  characters  of  spiders,  307. 

Canfield,  Dr.,  on  the  horns  of  the  AntUocapra,  265. 

Canine  teeth  in  man,  45;  diminution  of,  in  man,  60;  diminution  of, 
in  horses,  60;  disappearance  of,  in  male  rum'nants,  60;  large  in  the 
early  progenitors  of  man,  182. 

Canines  and  horns,  inverse  development  of,  586. 

Canoes,  use  of,  54,  205. 

CantJiaHs,  difference  of  color  in  the  sexes  of  a  species  of,  333. 

Canthaims  lineatus,  386. 

Capercailzie,  polygamous,  248;  proportion  of  the  sexes  in  the,  280; 
pugnacity  of  the  male,  412;  pairing  of  the,  416;  autumn  meetings  of 
the,  420;  call  of  the,  425;  duration  of  the  courtship  of,  460;  behaviour 
of  the  female,  476;  inconvenience  of  black  color  to  the  female,  505; 
sexual  difference  in  the  coloration  of  the,  559;  crimson  eyecere  of  the 
male,  559. 

Capitonidae,  colors  and  nidification  of  the,  518. 

Gapra  (Egagrus,  579;  crest  of  the  male,  606;  sexual  difference  in 
the  color  of,  612. 

Capreolus  Sibiricus  siibecaudatus,  619. 

Caprice,  common  to  man  and  animals,  105. 

Caprimidgus,  noise  made  by  the  males  of  some  species  of,  with 
their  wings,  426;  GapHmulgus  virginiamts,  pairing  of,  416. 

Carabidae,  343. 

Carbonnier,  on  the  natural  history  of  the  pike,  281  ;  on  the  rela- 
tive size  of  the  sexes  in  fishes,  380;  courtship  of  Chinese  Macropus, 
387. 

Carcineutes,  sexual  difference  of  color  in,  520. 

Carcinus  mmnas,  303,  304. 

Cardinalis  mrginianus,  255. 

Carduelis  degans,  sexual  differences  of  the  beak  in,  408. 

Carnivora,  marine,  polygamous  habits  of,  247  ;  sexual  differences 
in  the  colors  of,  610. 

Carp,  numerical  proportion  of  the  sexes  in  the,  282. 

Carr,  R.,  on  the  peewit,  414. 

Carrier  pigeon,  late  development  of  the  wattle  in  the,  269. 

Carrion  beetles,  stridulation  of,  342. 

Carrion-hawk,  bright  colored  female  of,  546. 

Cams,  Prof.  V. ,  on  the  development  of  the  horns  in  merino  sheep, 
266;  on  antlers  of  red  deer,  581. 

Cassowary,  sexes  and  incubation  of  the,  544. 

Castnia,  mode  of  holding  wings,  357. 

Castoreum,    604. 

Castration,  effects  of,  577. 

Casuarius  galeatus,  544. 

Cat,  convoluted  body  in  the  extremity  of  a  tail  of  a,  26;  sick,  sym- 
pathy of  a  dog  with  a,  116. 


730  INDEX. 

Cataract  in  CeJms  Azarm,  7. 

Catarrh,  liability  of  Gcbus  Azarm  to,  7. 

Catarrliine  monkeys,  174. 

Caterpillars,  bright  colors  of,  368. 

Cathartes  mira^  473;  cathartes  jota,  love-gestures  of  the  male,  432. 

Catlin,  (1.,  correlation  of  color  and  texture  of  hair  in  the  Mandans, 
225;  on  the  development  of  the  beard  among  North  American  In- 
dians, 639;  on  the  great  length  of  the  hair  in  some  North  American 
tribes,  662. 

Caton,  J.  D.,  on  the  development  of  the  horns  in  Cervtis  Virginia - 
nus  and  strongyloeeros,  265;  on  the  wild  turkey,  525;  on  the  pres- 
ence of  traces  of  horns  in  the  female  wapiti,  575;  on  the  fighting  of 
deer,  582;  on  the  crest  of  the  male  wapiti,  606;  on  the  colors  of  the 
Virginian  deer,  611;  on  sexual  differences  of  color  in  the  wapiti,  612; 
on  the  spots  of  the  Viginian  deer,  624. 

Cats,  dreaming,  84;  tortoise-shell,  260,  262,  269;  enticed  by  val- 
erian, 605;  colors  of,  620. 

Cattle,  rapid  increase  of,  in  South  America,  53;  domestic,  lighter  in 
winter  in  Siberia,  260;  horns  of,  266,  576;  domestic,  sexual  differ- 
ences of,  late  developed,  269,  numerical  proportion  of  the  sexes  in, 
279. 

Caudal  vertebrae,  number  of,  in  macaques  and  baboons,  65;  basal 
of  monkeys,  imbedded  in  the  body,  66. 

Cavolini,  observations  on  Serranus,  184. 

Cebus,  maternal  affection  in  a,  79;  gradation  of  species  of,  199; 
cebns  apeUa,  233;  cebus  azarcB,  liability  of,  to  the  same  diseases  as 
man,  7  ;  distinct  sounds  produced  by  95 ;  early  maturity  of  the 
female,  636;  cebus  capucinus,  polygamous,  245;  sexual  differences  of 
color  in,  613;  hair  on  the  head  of,  627;  cebus  vellerosus,  hair  on  the 
head  of,  627. 

Cecidomyiidae,  proportions  of  the  sexes  in,  286. 

Celibacy,  unknown  among  the  savages  of  South  Africa  and  South 
America,  678. 

Centipedes,  310. 

Cephalopoda,  absence  of  secondary  sexual  characters  in,  297. 

Cephalopterus  ornatus,  423;  cephalopterus  penduliger,  424. 

Cerarribyx  heros,  stridulant  organ  of,  343. 

Ceratodus,  paddle  of,  42. 

Ceratophora  aspera,  nasal  appendages  of,  403 ;  ceratophora  atod- 
dartii,  nasal  horn  of,  403. 

Cerceris,  habits  of,  330. 

Cercocebus  cethiops,  whiskers,  etc. ,  of,  629. 

Cercopithecus,  young,  seized  by  an  eagle  and  rescued  by  the  troop, 
115;  definition  of  species  of,  199;  cercopithecus  eephus,  sexual  differ- 
ence of  color  in,  614,  630;  cercopithecu^t  cynosurus  and  gHseo-viridis, 
color  of  the  scrotum  in,  614;  cercopithecus  Diana,  sexual  differences 
of  color  in,  614,  630;  cercopithecus  griseo-viridis,  114;  cercopithecus 
petaurista,  whiskers,  etc.,  of,  627. 

Ceres,  of  birds,  bright  colors  of,  559. 

Ceriornis  Temminckii,  swelling  of  the  wattles  of  the  male  during 
courtship,  434. 

Cervulus,  weapons  of,  586;  cervulus  moscliatus,  rudimentary  horns 
of  the  female,  574. 


INDEX,  t^l 

Cenrus  alces,  265;  eermiscampesti'ts,  odor  of,  604;  certym  mnadends, 
traces  of  boms  in  the  female,  574;  attacking  a  man,  582;  sexual  dif- 
ference in  the  color  of,  612;  cervus  ehipkus,  battles  of  male,  571; 
borns  of,  witb  numerous  points,  581;  long  bairs  on  tbe  tbroat  of, 
595;  cermis  eldi,  265. 

Cervus  inantehnricus,  623 ;  cervus  paludosus,  colors  of,  613 ; 
cermis  strongyloceros,  265  ;  cermis  virginianus,  265 ;  borns  of,  in 
course  of  modification,  584. 

Ceryle,  male  black-belted  in  some  species  of,  520. 

Cetacea,  nakedness  of,  63. 

Ceylon,  frequent  absence  of  beard  in  tbe  natives  of,  638. 

CbaflBncb,  projwrtion  of  tbe  sexes  in  tbe,  280;  courtsbip  of  the,  455. 

Cbatfincbes,  419;  new  mates  found  by,  464. 

Chalcophaps  indicus,  characters  of  young,  529. 

Ghalcosoma  atlas,  sexual  differences  of,  334. 

Ghamaleo,  sexual  differences  in  tbe  genus,  403;  combats  of,  405; 
hifurcus,  403,  404;    Owenii,  404;  pumilus,  405. 

Chanmpetes  unicol&r,  modified  wing-featber  in  the  male,  428. 

CHiameleons,  402. 

Chamois,  danger-signals  of,  114;  transfer  of  male  characters  to  an 
old  female,  574. 

Champneys,  Mr.,  acromio-basilar  muscle  and  quadrupedal  gait,  47. 

Chapman,  Dr.,  on  stridulation  in  Scolytus,  342. 

Cbapuis,  Dr. ,  on  tbe  transmission  of  sexual  peculiarites  in  pigeons, 
261;  on  streaked  Belgian  pigeons,  269,  507. 

Char,  male,  coloring  of,  during  the  breeding  season,  386. 

Characters,  male,  developed  in  females,  257;  secondary  sexual, 
transmitted  through  both  sexes,  257;  natural,  artificial,  exaggeration 
of,  by  man,  664. 

Charadrius  Jiiaticula  and  plumalis  sexes  and  young  of,  553. 

Chardin  on  the  Persians,  ^9. 

Charms,  worn  by  women,  659. 

Charruas,  freedom  of  divorce  amomg  the,  682. 

ChasmorhyncJius,  difference  of  color  in  the  sexes  of,  441;  colors 
of,  560;  \cliasm(yrliyrvchus  niveus,  441;  chasmarhynchus  nudicoUis,  441; 
cluismm'hynchus  tricaruncnlatus,  441. 

Chastity,  early  estimation  of,  134. 

Chatterers,  sexual  differences  in,  248. 

Cheever,  Rev.  H.  T. ,  census  of  the  Sandwich  Islands,  290. 

Cheiropetra,  absence  of  secondary  sexual  characters  in,  247. 

Chelae  of  Crustacea,  301,  307. 

Ghelonia,  sexual  differences  in,  397. 

C/ienalopex  CBgyptiacus,  wing-knobs  of,  414. 

Chera  progne,  445,  476. 

Chest,  proportions  of,  in  soldiers  and  sailors,  37;  large,  of  the 
Quechua  and  Aymara  Indians,  38. 

Chevrotains,  canine  teeth  of,  586. 

Chiasognathus,  stridulation  of,  346;  chiasognathtts  grantii,  mand- 
ibles of,  340. 

Children,  legitimate  and  illegitimate,  proportion  of  the  sexes 
in,  276.  &*-*-- 

Cbiloe,  lice  of  the  natives  of,  193;  population  of,  197. 
Chimcera  mojistrosa,  bony  process  on  the  head  of  the  male,  385. 


732  INDEX. 

Cliiiiiferoid  fisLes,  prehensile  organs  of  male,  375. 

C'Linipanzee,  640;  ears  of  the,  16;  representatives  of  the  eyebrows 
in  the,  21;  hands  of  the,  56;  absence  of  mastoid  processes  in  the,  59; 
platforms  built  by  the,  75;  cracking  nuts  with  a  stone,  91;  direction 
of  the  hair  on  the  arms  of  the,  172;  supposed  evolution  of  the,  202; 
polygamous  and  social  habits  of  the,  674. 

China,  North,  idea  of  female  beauty  in,  659;  China,  Southern,  in- 
habitants of,  224. 

Chinese,  use  of  flint  tools  by  the,  164;  difficulty  of  distinguishing 
the  races  of  the,  190;  color  of  the  beard  in,  637;  general  beardless- 
ness  of  the,  639;  opinions  of  the,  on  the  appearance  of  Europeans  and 
Cingalese,  659;  compression  of  the  feet  of,  665. 

Chinsurdi,  his  opinion  of  beards,  657,  663. 

GJdamydera  maculata,  433. 

Gliloeon,  pedunculated  eyes  of  the  male  of,  311. 

G hloephaga,  coloration  of  the  sexes  in,  524. 

Ghlorocoelus  tanana  (figured),  323. 

Chorda  dorsalis,  183. 

Chough,  red  beak  of  the,  559. 

Chromidae,  frontal  protuberance  in  male,  385;  sexual  differences  in 
color  of,  392. 

Ghrysemys  picta,  long  claws  of  the  male,  397. 

Ghrysococcyx,  characters  of  young  of,  529. 

Chrysomelidae,  stridulation  of,  342. 

Gicada  pruinosa,  320;  cicada  aeptendecim,  319. 

Cicadse,  songs  of  the,  319;  rudimentary  sound-organs  in  females  of, 
326. 

Cicatrix  of  a  burn,  causing  modification  of  the  facial  bones,  62. 

Gichla,  frontal  protuberance  of  male,  385. 

Cimetiere  du  Sud,  Paris,  24. 

Gincloramphus  cruralis,  large  size  of  male,  411. 

Ginclus  aquaticus,  518. 

('ingalese,  Chinese  opinion  of  the  appearance  of  the,  659. 

Cirripedes,  complemental  males  of,  235. 

Civilization,  effects  of,  upon  natural  selection,  151;  influence  of,  in 
the  competition  of  nations,  208. 

Clanging  of  geese,  etc.,  418. 

Claparede,  E.,  on  natural  selection  applied  to  man,  55. 

(Marke,  on  the  marriage-customs  of  Kalmucks,  683. 

Classification,  168. 

Claus,  C,  on  the  sexes  of  Saphirina,  306. 

Cleft-palate,  inherited,  40. 

GlimacteHs  erytJirops,  sexes  of,  546. 

Climate,  35;  cool,  favorable  to  human  progress,  150;  power  of 
supporting  extremes  of,  by  man,  207;  want  of  connection  of,  with 
color,  219;  direct  action  of,  on  colors  of  birds,  480. 

Cloaca,  existence  of  a,  in  the  early  progenitors  of  man,  182. 

Cloacal  passage  existing  in  the  human  embryo,  10. 

Clubs,  used  as  weapons  before  dispersion  of  mankind,  204. 

Clucking  of  fowls,  417. 

Glythra  A-piinctnta,  stridulation  of,  342. 

Coan,  Mr.,  Sandwich  Islanders,  213. 

Cobbe,  Miss,  on  morality  in  hypothetical  bee- community,  113. 


INDEX.  733 

Cobra,  ingenuity  of  a,  399. 

Coccus,  167. 

Coccyx,  25;  in  the  human  embryo,  10;  convoluted  body  at  the 
extremity  of  the,  25;  imbedded  in' the  body,  66. 

Cochin-China,  notions  of  beauty  of  the  inhabitants  of,  659,  661. 

Cock,  blind,  fed  by  its  companion,  116;  game,  killing  a  kite,  412; 
comb  and  wattles  of  the.  457;  preference  shown  by  the,  for  the 
young  hens,  477;  game,  transparent  zone  in  the  hackles  of  a,  489. 

Cock  of  the  rock,  460. 

Cockatoos,  559,  560,  562;  nestling,  467;  black,  immature  plumage 
of,  532. 

Coelenterata,  absence  of  secondary  sexual  characters  in,  494. 

Coffee,  fondness  of  monkeys  for,  7. 

Cold,  supposed  effects  of,  35;  power  of  supporting,  by  man,  207. 

Coloptera,  333;  stridulation  of,  322;  stridulant  organs  of,  discussed, 
344. 

Colias  edusa  and  hyale,  361. 

Collingwood,  C,  on  the  pugnacity  of  the  butterflies  of  Borneo,  348; 
on  butterflies  being  attracted  by  a  dead  specimen  of  the  same 
species,  360. 

Colobus,  absence  of  the  thumb,  57. 

Colombia,  flattened  heads  of  savages  of,  655. 

Colonists,  success  of  the  English  as,  160. 

Coloration,  protective,  in  birds,  556. 

Color,  supposed  to  be  dependent  on  light  and  heat,  36;  correlation 
of,  with  immunity  from  certain  poisons  and  parasites,  220;  purpose 
of,  in  lepidoptera,  359;  relation  of,  to  sexual  functions  in  fishes,  388; 
difference  of,  in  the  sexes  of  snakes,  398;  sexual  differences  of,  in 
lizards,  405;  influence  of,  in  the  pairing  of  birds  of  different  species, 
472;  relation  of,  to  nidification,  515,  519;  sexual  differences  of,  in 
mammals,  609,  616;  recognition  of,  by  quadrupeds,  617;  of  children, 
in  different  races  of  man,  635;  of  the  skin  in  man,  690. 

Colors,  admired  alike  by  man  and  animals,  104;  bright,  due  to 
sexual  selection,  295;  bright,  among  the  lower  animals,  295,  296; 
bright,  protective  to  butterflies  and  moths,  354;  bright,  in  male 
fishes,  380,  385;  transmission  of,  in  birds,  509. 

Colquhoun,  example  of  reasoning  in  a  retriever,  88. 

Colurriba  passerina,  young  of,  532. 

Colymhns  glacialis,  anomalous  young  of,  550. 

Comb,  development  of,  in  fowls,  270. 

Combs  and  wattles  in  male  birds,  457. 

Community,  preservation  of  variations  useful  to  the,  by  natural 
selection,  70. 

Complexion,  different  in  men  and  women,  in  an  African  tribe.  63^^, 

C-ompositsB,  gradation  of  species  among  the,  199. 

Comte,  C,  on  the  expression  of  the  ideal  of  beauty  by  sculpture, 
663. 

Conditions  of  life,  action  of  changed,  upon  man,  34;  influence  of, 
on  plumage  of  birds,  538. 

Condor,  eyes  and  comb  of  the,  484. 

Conjugations,  origin  of,  103. 

Conscience,  110,  131,  143;  absence  of,  in  some  criminals,  131. 

Constitution,  difference  of,  in  different  races  of  men,  191. 


734  INDEX, 

Consumption,  liability  of  Gebu8  Azarm  to,  7;  connection  between 
complexion  and,  221. 

Convergence  of  characters,  201. 

Cooing  of  pigeons  and  doves,  425. 

Cook,  Capt. ,  on  the  nobles  of  the  Sandwich  Islands,  669. 

Cope,  E.  D.,  on  the  Dinosauria,  180. 

Cophotis  ceylanica,  sexual  differences  of,  402,  405. 

Cop/'is,  336;  copns  isidis,  sexual  differences  of,  335;  copris  lunaria, 
stridulation  of,  343. 

Corals,  bright  colors  of,  295. 

Coral-snakes,  400. 

Cordylus,  sexual  difference  of  color  in  a  species  of,  405. 

Corfu,  habits  of  the  chaffinch  in,  281. 

Cornelius,  on  the  proportion  of  the  sexes  in  Lucanus  Cervus,  286. 

Corpora  Wolffina,  183;  agreement  of,  with  the  kidneys  of  fishes,  10. 

Correlated  variation,  49. 

Correlation,  influence  of,  in  the  production  of  races,  225. 

Corse,  on  the  mode  of  fighting  of  the  elephant,  585. 

Corvus  cor  one,  463 ;  Corvus  graculus,  red  beak  of,  559 ;  Corvus 
pica,  nuptial  assembly  of,  461. 

Corydalis  cornutus,  large  jaws  of  the  male,  312. 

Cosmetornis,  457,  526. 

Cosmetornis  vexillarius,  elongation  of  wing-feathers  in,  436,  457. 

Cotingidae,  sexual  differences  in,  248;  coloration  of  the  sexes  of, 
523;  resemblance  of  the  females  of  distinct  species  of,  535. 

Coitus  sco^'pius,  sexual  differences  in,  382. 

Coulter,  Dr.,  on  the  Californian  Indians,  291. 

Counting,  origin  of,  163;  limited  power  of,  in  primeval  man,  205. 

Courage,  variability  of,  in  the  same  species,  78;  universal  high 
appreciation  of,  139;  importance  of,  147;  characteristic  of  men,  644. 

Courtship,  greater  eagerness  of  males  in,  250;  of  fishes,  376,  386; 
of  birds,  417,  426,  460. 

Cow,  winter  change  of  color,  619. 

Crab,  devil,  304;  crab,  shore,  habits  of,  303. 

Crcibro  cribrarius,  dilated  tibiae  of  the  male,  313. 

Crabs,  proportions  of  the  sexes  in,  288. 

Cranz,  on  the  inheritance  of  dexterity  in  seal-catching,  37. 

Crawfurd,  on  the  number  of  species  of  man,  199. 

Crenilabrus  massa  and  0.  melops,  nests,  built  by,  391. 

Crest,  origin  of,  in  Polish  fowls,  261. 

Crests,  of  birds,  difference  of,  in  the  sexes,  533;  dorsal  hairy,  of 
mammals,  606. 

Cricket,  field,  stridulation  of  the,  320,  321;  pugnacity  of  male,  327; 
cricket,  house,  stridulations  of  the,  321. 

Crickets,  sexual  differences  in,  328. 

Crinoids,  complexity  of,  103. 

Crioceridae,  stridulation  of  the,  342. 

Croaking  of  frogs,  397. 

Crocodiles,  musky  odor  of,  during  the  breeding  season,  39§. 

Crocodilia,  398. 

Crossbills,  characters  of  young,  529. 

Crosses  in  man,  196. 

Crossing  of  races,  effects  of  the,  218,. 


INDEX,  735 

CrasaoptUon  auritum,  454,  514,  538;  adornment  of  both  sexes  of, 
267;  sexes  alike  in,  524. 

Crotch,  G.  R.,  on  the  stridulation  of  beetles,  342,  345,  on  the 
stridulation  of  Heliopathea,  345;  on  the  stridulation  of  Addles,  346; 
habit  of  female  deer  at  breeding  time,  574. 

Crow  Indians,  long  hair  of  the,  662;  young  of  the,  549. 

Crows,  559;  vocal  organs  of  the,  421;  living  in  triplets,  465;  crows, 
carrion,  new  mates  found  by,  463;  crows,  Indian,  feeding  their  blind 
companions,  116. 

Cruelty  of  savages  to  animals,  133. 

Crustacea,  parasitic,  loss  of  limbs  by  female,  235;  prehensible  feet 
and  antennae  of,  237;  male,  more  active  than  female,  250;  partheno- 
genesis in,  287;  secondary  sexual  characters  of,  299;  amphipod,  males 
sexually  mature  while  young,  552;  auditory  hairs  of,  648. 

Crystal  worn  in  the  lower  lip  by  some  Central  African  women,  656. 

Cuckoo  fowls,  270. 

Culicidae,  235,  318;  attracted  by  each  other's  humming,  318. 

Cullen,  Dr.,  on  the  throat-pouch  of  the  male  bustard,  423. 

Cultivation  of  plants,  probable  origin  of,  151. 

Cupples,  Mr.,  on  the  numerical  proportion  of  the  sexes  in  dogs, 
sheep  and  cattle,  279;  on  the  Scotch  deerhound,  589;  on  sexual 
preference  in  dogs,  597. 

Curculionidae,  sexual  diflFerence  in  length  of  snout  in  some,  236; 
hornlike  processes  in  male,  338;  musical,  341,  342. 

Curiosity  manifestations  of,  by  animals,  80. 

Curlews,  double  moult  in,  442. 

Cursores,  comparative  absence  of  sexual  differences  among  the,  248. 

Curtis,  J.,  on  the  proportion  of  the  sexes  in  Athalia,  286. 

Cuvier,  F.,  on  the  recognition  of  women  by  male  quadrumana,  9; 
Cuvier,  G.,  on  the  number  of  caudal  vertebrae  in  the  mandril,  65;  on 
instinct  and  intelligence,  75;  views  of,  as  to  the  position  of  man,  170; 
on  the  position  of  the  seals,  170;  on  Hectocotyle,  297. 

Cyanakyoiif  sexual  difference  in  colors  of,  520;  immature  plumage 
of,  532. 

Cyanectda  »uecica,  sexual  differences  of,  537. 

Cychrus,  sounds  produced  by,  345, 

Cycnia  mendica,  sexual  difference  of,  in  color,  358. 

Cygnus  ferus^  trachea  of,  424;  cygnus  immutabUis,  550;  eygnus 
olor,  white  young  of,  550. 

CyUo  Leda,  instability  of  the  ocellated  spots  of,  486. 

Cynanthus  ,  variation  in  the  genus,  481. 

Cynipidae,  proportion  of  the  sexes  in,  286. 

CynocepJudus,  difference  of  the  young  from  the  adult,  9;  male 
recognition  of  women  by,  9;  polygamous  habits  of  species  of,  246; 
cynocephidus  bfdxmin,  710;  cynocephalus  cJuicma,  79;  cynocephalus 
gelada,  92;  cynocepJuilus  Junnadryas,  92,  674;  sexual  difference  of 
color  in,  614,  710;  cynocephalus  leucophus,  colors  of  the  sexes  of, 
614,  710;  cynocephalus  mormony  colors  of  the  male,  614,  710 ;  Cyno- 
ceplcalus  porcaHus,  mane  of  the  male,  594;  cynocephalus  sphinx,  710. 

(Jynopitheeus  niger,  ear  of,  18. 

(Jypridina,  proportions  of  the  sexes  in,  287. 

Cyprinidae,  proportion  of  the  sexes  in  the,  282;  cyprinidae,  Indian, 


736  INDBX. 

Crprinodontidte,  sexaal  differences  in  the,  880,  882. 

(Mrinui  auratus,  388. 

C^fpris,  relations  of  the  sexes  in,  287. 

Cyriodaetylw  rvbidus,  402. 

dyttaphora  eristata,  hood  of,  603. 

Daceto,  sexual  difference  of  color  in,  520;  daeelo  gaudiehaudi, 
young  male  of,  532. 

Dal-ripa,  a  kind  of  ptarmigan,  280. 

DanujUu  a&ifrons,  peculiar  markings  of,  621 ;  damalis  pygarga, 
peculiar  markings  of,  621. 

Dampness  of  climate,  supposed  influence  of,  on  the  color  of  the 
skin,  35,  220. 

Danaidse,  350. 

Dances  of  birds,  431. 

Dancing,  universality  of,  203. 

Danger  signals  of  animal,  114. 

Daniell,  Dr.,  his  experience  of  residence  in  West  Africa,  223. 

Darfur,  protuberances  artificially  produced  by  natives  of,  655. 

Darwin,  F.,  on  the  stridulation  of  Dermestes  murinv*,  342. 

Ikuychira  pudibunda,  sexual  difference  of  color  in,  358. 

Davis,  A.  H.,  on  the  pugnacity  of  the  male  stag-beetle,  339;  Davis, 
J.  B.,  on  the  capacity  of  the  skull  in  various  races  of  men,  60;  on 
the  beards  of  the  Polvnesians,  639. 

Death's  Head  Sphinx,  349. 

Death-rate  higher  in  towns  than  in  rural  districts,  157. 

Death-tick,  347. 

De  Candolle,  Alph.,  on  a  case  of  inherited  power  of  moving  the 
scalp,  14. 

Declensions,  origin  of,  103. 

Decoration  in  birds,  434. 

BecHcus,  323. 

Deer,  265;  development  of  the  horns  in,  265;  spots  of  young,  529, 
624;  horns  of,  573,  578;  use  of  horns  of,  582,  590;  horns  of  a,  in 
course  of  modification,  584;  size  of  the  horns  of.  587;  female,  pair- 
ing with  one  male,  while  others  are  fighting  for  her,  595;  male, 
attracted  by  the  voice  of  the  female,  600;  male,  odor  emitted  by  605; 
Axis,  sexual  difference  in  the  color  of  the,  612;  fallow,  different 
colored  herds  of,  617;  Mantchurian,  623;  Virginian,  624;  color  of 
the,  not  affected  by  castration,  611;  colors  of,  612. 

Deerhound,  Scotch,  greater  size  of  the  male,  269,  589. 

Defensive  orders  of  mammals,  590. 

De  Geer,  C,  on  a  female  spider  destrojnLng  a  male,  308. 

De  Kay,  Dr..  on  the  bladder-nose  seal,  603. 

Delorenzi,  G.,  division  of  malar  bone,  44. 

Demerara,  yellow  fever  in,  221. 

Dendroeygna,  529. 

DendrophUa  frontalis,  young  of,  555. 

Denison,  Sir  W.,  manner  of  ridding  themselves  of  vennin  among 
the  Australians,  64;  extinction  of  Tasmanians,  209. 

Denny.  H.,  on  the  lice  of  domestic  animals,  193. 

DermetUs  murinus,  stridulation  of,  342. 
.    Descent  traced  through  the  mother  alone,  672. 

Deserts,  protective  coloring  of  animals  inhabiting,  557, 


IKDMX. 


737 


738  INDEX, 

84;  diverging  when  drawing  sledges  over  thin  ice,  85;  exercise  of 
reasoning  faculties  by,  88;  domestic,  progress  of,  in  moral  qualities, 
90;  distinct  tones  uttered  by,  95;  parallelism  between  his  affection 
for  his  master  and  religious  feeling,  108;  sociability  of  the,  IIB; 
sympathy  of,  with  a  sick  cat,  116;  sympathy  of,  with  his  master, 
116  ;  their  possession  of  conscience,  117;  possible  use  of  the  hair 
on  the  fore  legs  of  the,  172;  races  of  the,  201;  numerical  proportion 
of  male  and  female  births  in,  278;  sexual  affection  between  individ- 
uals of,  215;  howling  at  certain  notes,  649;  rolling  in  carrion,  605. 

Dolichocephalic  structure,  possible  cause  of,  63. 

Dolphins,  nakedness  of,  63. 

Domestic  animals,  races  of,  201 ;  change  of  breeds  of,  680. 

Domestication,  influence  of,  in  removing  the  sterility  of  hybrids, 
196. 

D'Orbigny,  A.,  on  the  influence  of  dampness  and  dryness  on  the 
color  of  the  skin,  220;  on  the  Yuracaras,  661. 

Dotterel,  544. 

Doubleday,  E.,  on  sexual  differences  in  the  wings  of  butterflies, 
314;  H.,  on  the  porportion  of  the  sexes  in  the  smaller  moths,  284; 
males  of  Lasiocampa  quercus  and  on  the  attraction  of  the  Satumia 
carpini  by  the  female,  284 ;  on  the  proportion  of  the  sexes  in  the 
Lepidoptera,  284;  on  the  ticking  of  Anobium  tesselatum,  347;  on  the 
structure  of  Ageronia  ferania,  349;  on  white  butterflies  alighting 
upon  paper,  359. 

Douglas,  J.  W-,  on  the  sexual  differences  of  the  Hemiptera,  318; 
colors  of  British  Homoptera,  318. 

Down,  of  birds,  442. 

Draco,  gular  appendages  of,  402. 

Dragonet,  Gemmeous,  381. 

Dragon-flies,  caudal  appendages  of  male,  313  ;  relative  size  of  the 
sexes  of,  316;  difference  in  the  sexes  of,  328;  want  of  pugnacity  by 
the  male,  330. 

Drake,  breeding  plumage  of  the,  446. 

Dreams,  84;  possible  source  of  the  belief  in  spiritual  agencies,  107. 

Drill,  sexual  difference  of  6olor  in  the,  614. 

Drommus  irroratus,  545. 

Dromolcea,  Saharan  species  of,  519. 

Drongo  shrike,  524. 

Drongos,  racket-shaped  feathers  in  the  tails  of,  436,  445. 

Dryness  of  climate,  supposed  influence  of,  on  the  color  of  tin' 
skin,  220. 

Drp(>])it?i€cus,  177. 

Duck,  harlequin,  age  of  mature  plumage  in  the,  552;  breeding  in 
immature  ])lumage,  552;  long-tailed,  preference  of  male,  for  certain 
females,  478;  pintail,  pairing  with  a  widgeon,  471;  voice  of  the,  425; 
pairing  with  a  shield-drake,  471  ;  immature  plumage  of  the,  5H2; 
wild,  sexual  differences  in  the,  248;  speculum  and  male  characters  of, 
267;  pairing  with  a  pintail  drake,  471. 

Ducks,  wild,  becoming  polygamous  under  partial  domestication, 
249;  dogs  and  cats  recognized  by,  468. 

Dufosse,  Dr.,  sounds  produced  by  fish,  393. 

Dugong,  nakedness  of,  63;  tusks  of,  572. 

Dujardin,  on  the  relative  size  of  the  cerebral  ganglia  in  ipsects,  61, 


INDEX.  739 

Duncan,  Dr.,  on  the  fertility  of  early  marriages,  156,  comparative 
health  of  married  and  single,  159. 

Dupont,  M.,  on  the  occurrence  of  the  supra-condyloid  foramen  in 
the  humeius  of  man,  24. 

Durand,  J.  P..  on  causes  of  variation,  34. 

Bureau  de  la  Malle,  on  the  songs  of  birds,  97;  on  the  acquisition 
of  an  air  by  blackbirds,  421. 

Dutch,  retention  of  their  color  by  the,  in  South  Africa,  319. 

Duty,  sense  of   110. 

Duvaucel,  female  Uylobates  washing  her  young,  79. 

Dyaks,  pride  of,  in  mere  homicide,  132. 

Dytmstes,  large  size  of  males  of,  316. 

Dynastini,  stridulation  of,  344. 

Dytisciis,  dimorphism  of  females  of,  313;  grooved  elytra  of  the 
female,  313. 

Eiagle,  young  Cercopithecus  rescued  shell,  by  the  troop,  115;  cer- 
copithecus,  white-headed,  breeding  in  immature  plumage,  552. 

Eagles,  golden,  new  mates  found  by,  463. 

Ear,  motion  of  the,  15;  external  form  of  the,  useless  in  man,  15; 
rudimentary  point  of  the,  in  man,  16. 

Ears,  more  variable  in  men  than  women,  253;  piercing  and  orna- 
mentation of  the,  656. 

Earwigs,  parental  feeling  in,  120. 

Echidna,  178. 

Echini,  bright  colors  of  some,  295. 

Ekihinodermata,  absence  of  secondary  sexual  characters  in,  294. 

Kchis  carinata,  400. 

Ecker,  figure  of  the  human  embryo,  11;  on  the  development  of  the 
gyri  and  sulci  of  the  brain,  232;  on  the  sexual  differences  in  the 
pelvis  in  man,  635;  on  the  presence  of  a  sagittal  crest  in  Australians, 
636. 

Edentata,  former  wide  range  of,  in  America,  193;  absence  of  secon 
dary  sexual  characters  in,  246. 

Edolius,  racket-shaped  feathers  in,  436. 

Edwards,  Mr. ,  on  the  proportion  of  the  sexes  in  North  American 
species  of  PapUio,  283. 

Eels,  hermaphroditism  of,  184. 

Egerton,  Sir  P.,  on  the  use  of  the  antlers  of  deer,  581,  582;  on  the 
pairing  of  red  deer,  595;  on  the  bellowing  of  stags,  601. 

Eggs,  hatched  by  male  fishes,  391. 

Egret,  Indian,  sexes  and  young  of,  553. 

Egrets,  breeding  plumage  of,  442;  white,  560. 

Elirenberg,  on  the  mane  of  the  male  Hamadryas  baboon,  594. 

Ekstrom,  M.,  on  Ilarclda  glacifilis,  478. 

Elachista  rufocinerea,  habits  of  male,  284. 
,    Eland,  development  of  the  horns  of  the,  265. 

Elands,  sexual  differences  of  color  in,  611. 

Elaphomyia,  sexual  differences  in,  317. 

Elaphrus  uliginosua,  stridulation  of,  343. 

Elnps,  400. 

Elateridae,  proportion  of  the  sexes  in,  286. 

Elaters,  luminous,  315. 

Elephant,  178;  rate  of  increase  of  the,  53;  nakedness  of  the,  63; 


740  INDEX. 

using  a  fan,  91 ;  Indian,  forbearance  to  liis  keeper,  117;  polygamous 
habits  of  the,  246;  pugnacity  of  the  male,  571;  tusks  of,  572,  573, 
578,  587;  Indian,  mode  of  fighting,  of  the,  585;  male,  odor  emitted 
by  the,  604;  attacking  white  or  grey  horses,  617. 

Elevation  of  abode,  modifying  iniiuence  of,  39. 

Elimination  of  inferior  individuals,  155. 

Elk,  579;  winter  change  of  the,  619;  Irish,  horns  of  the,  587. 

EUice  Islands,  beards  of  the  natives,  639,  663. 

Elliot,  D.  G.,  on  Pelecanus  erythrorhynchus,  442;  R.,on  the  nu- 
merical proportion  of  the  sexes  in  young  rats,  279;  on  the  proportion 
of  the  sexes  in  sheep,  278;  Sir  W.  on  the  polygamous  habits  of  the 
Indian  wild  boar,  246. 

Ellis,  on  the  prevalence  of  infanticide  in  Polynesia,  676. 

Elphinstone,  Mr.,  on  local  difference  of  stature  among  the  Hindoes, 
35;  on  the  difficulty  of  distinguishing  the  native  races  of  India,  190. 

Elytra,  of  the  females  of  Dytiscus,  AcUius.IIydroporus,  313. 

Emberiza,  characters  of  young,  529;  Emberiza  miliaria,  529; 
Emberiza  schmniclu<i,  468;  head-feathers  of  the  male,  455. 

Embryo  of  man,  10,  11;  of  the  dog,  11. 

Embryos  of  mammals,  resemblance  of  the,  28. 

Emigration,  155. 

Emotions  experienced  by  the  lower  animals  in  common  with  man, 
77;  manifested  by  animals,  80. 

Emperor  butterfly,  348. 

Emperor  moth,  358. 

Emu,  sexes  and  incubation  of,  545. 

Emulation  of  singing  birds,  419. 

Endurance,  estimation  of,  134. 

Energy,  a  characteristic  of  men,  645. 

England,  numerical  proportion  of  male  and  female  births  in,  274. 

Engleheart,  Mr.,  on  the  finding  of  new  mates  by  starlings,  464. 

English,  success  of,  as  colonists,  160. 

Engravers,  short-sighted,  37. 

Entomostraca,  304. 

Entozoa,  difference  of  color  between  the  males  and  females  of 
some,  294. 

Environment,  direct  action  of  the,  in  causing  differences  between 
the  sexes,  254. 

Envy,  persistence  of ,  127. 

Eocene  period,  possible  divergence  of  men  during  the,  177. 

Eolidae,  colors  of,  produced  by  the  biliary  glands,  296. 

Epeira  nigra,  small  size  of  the  male  of,  308. 

Ephemerae,  311. 

Ephemeridae,  328. 

Ephippiger  vitium,  stridulating  organs  of,  322,  326. 

Epicalia,  sexual  differences  of  coloring  in  the  species  of,  350. 

Equus  hemionus,  winter  change  of,  619. 

Erateina,  coloration  of,  357. 

Ercolani,  Prof.,  hermaphroditism  in  eels,  184. 

Erect  attitude  of  man,  57,  58. 

Eristalis,  courting  of  318. 

Eschricht,  on  the  development  of  hair  in  man,  20;  on  a  lanuginous 
mustache  in  a  female  fetus,  21 ;  on  the  want  of  definition  between 


INi)EX.  741 

tlie  scalp  and  the  forehead  in  some  children,  171;  on  the  arrange- 
ment of  the  hair  in  the  human  fetus,  172;  on  the  hairyness  of  the 
face  in  the  human  fetus  of  both  sexes,  688,  689. 

Esmeralda,  difference  of  color  in  the  sexes  of,  334. 

Esax  Indus,  281 ;  esox  reticulatus,  386. 

Esquimaux,  72,  150;  their  belief  in  the  inheritance  of  dexterity  in 
seal-catching,  37;  mode  of  life  of,  224. 

Estrtlda  amnndava,  pugnacity  of  the  male,  415. 

Eubagis,  sexual  differences  of  coloring  in  the  species  of,  351. 

Euchirus  longimanus,  sound  produced  by,  344. 

Eudromias  moi^inellus,  544. 

Eulampis  jugulaiHs,  colors  of  the  female,  516. 

Euler,  on  the  rate  of  increase  in  the  U.  S.,  50. 

Eumomota  stipercUiaris,  racket-shaped  feathers  in  the  tail  of,  436. 

Eupetomena  macroura,  colors  of  the  female,  516. 

Euphema  splendida,  521. 

Euplocamiis  erythrophthalmus,  possession  of  spurs  by  the  female, 
413. 

Europe,  ancient  inhabitants  of,  206. 

Europeans,  difference  of,  from  Hindoos,  218;  hairyness  of,  proba- 
bly due  to  reversion,  687. 

Eurostopodus,  sexes  of,  546. 

Eurygnathus,  different  proportions  of  the  head  in  the  sexes  of, 
314. 

Eustephanus,  sexual  differences  of  species  of,  408;  young  of,  555. 

Exaggeration  of  natural  characters  by  man,  664. 

Exogamy,  673,  675. 

Experience,  acquisition  of,  by  animals,  90. 

Expression,  resemblances  in,  between  man  and  the  apes,  171. 

Extinction  of  races,  causes  of,  206. 

Eye,  destruction  of  the,  36;  change  of  position  in,  62;  obliquity 
of,  regarded  as  a  beauty  by  the  Chinese  and  Japanese,  659. 

Eyebrows,  elevation  of,  14;  development  of  long  hairs  in,  20;  in 
monkeys,  171;  eradicated  in  parts  of  South  America  and  Africa,  656; 
eradication  of,  by  the  Indians  of  Paraguay,  662. 

Eyelashes,  eradication  of,  by  the  Indians  of  Paraguay,  662. 

Eyelids,  colored  black,  in  part  of  Africa,  655. 

Eyes,  pillared,  of  the  male  of  GJdo'eon,  311;  difference  in  the  color 
of,  in  the  sexes  of  birds,  483. 

Eyton,  T.  C. ,  observations  on  the  development  of  the  horns  in  the 
fallow  deer,  265. 

Eyzies,  Les,  human  remains  from,  207. 

Fabre,  M.,  on  the  habits  of  Cerceris,  330. 

Facial  bones,  causes  of  modification  of  the,  62. 

Faculties,  diversity  of,  in  the  same  race  of  men,  30;  inheritance 
of,  31;  diversity  of,  in  animals  of  the  same  species,  31;  mental  varia- 
tion of,  in  the  same  species,  74;  of  birds,  466. 

Fakirs,  Indian,  tortures  undergone  by,  134. 

Falco  leiicoceplialus,  552;  falco  peregrinus,  463,  524;  falco  tinnun- 
culus,  463. 

Falcon,  peregrine,  new  mate  found  by,  463. 

Falconer,  H.,  on  the  mode  of  fighting  of  the  Indian  elephant,  585; 
on  canines  in  a  female  deer,  586;  on  Ilyomoschus  aquaticus,  624. 


742  INDEX. 

Falkland  Islands,  horses  of,  206. 

Fallow-deer,  different  colored  herds  of,  617. 

Famines,  frequency  of,  among  savages,  51. 

Farr,  Dr.,  on  the  effects  of  profligacy,  155;  on  the  influence  of 
marriage  on  mortality,  157,  158. 

Farrar,  F.  W.,  on  the  origin  of  language,  98;  on  the  crossing  or 
blending  of  languages,  102;  on  the  absence  of  the  idea  of  Ood  in 
certain  races  of  men,  105;  on  early  marriages  of  the  poor,  156;  on 
the  middle  ages,  160. 

Farre,  Dr. ,  on  the  structure  of  the  uterus,  43. 

Fashions,  long  prevalence  of,  among  savages,  658,  666. 

Faye,  Prof.,  on  the  numerical  proportion  of  male  and  female  births 
in  Norway  and  Russia,  275;  on  the  greater  mortality  of  male  children 
at  and  before  birth,  275. 

Feathers,  modified,  producing  sounds,  427  et  seq.,  512;  elongated, 
in  male  birds,  435,  457;  racket-shaped,  436;  barbless  and  with  fila- 
mentous barbs  in  certain  birds,  437;  shedding  of  margins  of,  446. 

Feeding,  high,  probable  influence  of,  in  the  pairing  of  birds  of 
different  species,  472. 

Feet,  thickening  of  the  skin  on  the  soles  of  the,  37;  modification 
of,  in  man,  58. 

Fdis  canadensis,  throat-ruff  of,  594;  felis  pardalis  and  F.  mitis, 
sexual  difference  in  the  coloring  of,  610. 

Female,  behavior  of  the,  during  courtship,  178;  birds,  differences 
of,  536. 

Females,  presence  of  rudimentary  male  organs  in,  184;  preference 
of,  for  certain  males,  242;  pursuit  of,  by  males,  250;  occurrence  of 
secondary  sexual  characters  in,  255;  development  of  male  character 
by,  257. 

Females  and  males,  comparative  numbers  of,  241,  244;  compar- 
ative mortality  of,  while  young,  244. 

Femur  and  tibia,  proportions  of,  in  the  Aymara  Indians,  39. 

Fenton,  Mr.,  decrease  of  Maories,  210;  infanticide  among  the 
Maories,  289. 

Ferguson,  Mr.,  on  the  courtship  of  fowls,  474. 

Fertilization,  phenomena  of,  in  plants,  251;  in  the  lower  animals, 
251. 

Fertility  lessened  under  changed  conditions,  214. 

Fevers,  immunity  of  negroes  and  mulattoes  from,  220. 

Fiber  zibethicus,  protective  coloring  of  it,  619. 

FJck,  H.,  effect  of  conscription  for  military  service,  152. 
.    Fidelity,  in   the   elephant,  117;  of  savages  to   one  another,  133; 
importance  of,  141. 

Field  slaves,  difference  of,  from  house  slaves,  224. 

Fiji  Archipelago,  population  of  the,  198;  Fiji  Islands,  beards  of 
the  natives,  639,  663;  marriage  customs  of  the,  683. 

Fijians,  burying  their  old  and  sick  parents  alive,  116;  estimation 
of  the  beard  among  the,  663;  admiration  of,  for  a  broad  occiput,  665. 

Filial  affection,  partly  the  result  of  natural  selection,  119. 

Filum  terminale,  25. 

Finch,  racket-shaped  feathers  in  the  tail  of  a,  436. 

Finches,  spring  change  of  color  in,  447;  British,  females  of  the,  536. 

Fingers,  partially  coherent,  in  species  of  Hylobates,  57. 


tNDEl,  743 

Finlavson,  on  the  Cochin  Chinese,  659 

Fire,  use  of,  54,  164.  204. 

Fischer,  on  the  pugnacity  of  the  male  of,  Lethrus  cep7ialotes,  340. 

Fischer,  F.  Von,  on  display  of  brightly  colored  parts  by  monkeys 
in  courtship,  709. 

Fish,  eagerness  of  male,  250;  proportion  of  the  sexes  in,  281; 
sounds  produced  by,  393. 

Fishes,  kidneys  of,  represented  by  Corpora  Wolffiana  in  the  human 
embryo,  10;  male  hatching  ova  in  their  mouths,  185;  receptacles  for 
ova  possessed  by,  235;  relative  size  of  the  sexes  in,  380;  fresh  water, 
of  the  tropics,  389;  protective  resemblance  in,  390;  change  of  color 
in,  390;  nest-building,  391;  spawning  of,  392;  sounds  produced  by, 
393,  640;  continued  growth  of,  552. 

Flamingo,  age  of  mature  plumage,  551. 

Flexor  poUicis  longus,  similar  variation  of,  in  man,  48. 

Flies,  humming  of,  318. 

Flint  tools,  164. 

Flints,  difficulty  of  chipping  into  form,  56. 

Florida,  Quiscalus  majm'  in,  281. 

Florisuga  meUivara,  504. 

Flounder,  coloration  of  the,  390. 

Flower,  W.  H  ,  on  the  abductor  of  the  fifth  metatarsal  in  apes, 
47;  on  the  jwsition  of  the  seals,  170;  on  the  Pitlieda  Tnonachus,  229; 
on  the  throat  pouch  of  the  male  bustard,  423. 

Fly-catchers,  colors  and  nidification  of,  518. 

Fetus,  human,  woolly  covering  of  the,  21;  arrangement  of  the 
hair  on,  172. 

Food,  influence  of,  upon  stature,  35. 

Foot,  prehensile  power  of  the,  retained  in  some  savages,  58;  pre- 
hensile, in  the  early  progenitors  of  man,  182. 

Foramen,  supra-condyloid,  exceptional  occurrence  of  in  the 
humerus  of  man,  24,  49;  in  the  early  progenitors  of  man,  179. 

Forbes,  D.,  on  the  Aymara  Indians,  39;  on  local  variation  of  color 
in  the  Quichuas,  223;  on  the  hairlessness  of  the  Aymaras  and 
Qaichuas,  639;  on  the  long  hair  of  the  Aymaras  and  Quichuas,  637, 
662 

Forel,  F.,  on  white  young  swans,  550. 

Forester,  Hon.  O.  W.,  on  an  orphan  hawk,  465. 

Formicn  rufa,  size  of  the  cerebral  ganglia  in,  61. 

Fossils,  absence  of,  connecting  man  with  the  apes,  178. 

Fowl,  occurrence  of  spurs  in  the  female,  257;  game,  early  pugnac- 
ity of,  270;  Polish,  early  development  of  cranial  peculiarities  of,  270; 
variations  in  plumage  of,  438;  examplas  of  correlated  development  in 
the,  484,  domestic,  breeds  and  sub  breeds  of,  523. 

Fowls,  spangled  Hamburg,  259,  270,  inheritance  of  changes  of  plu- 
mage by,  259,  sexual  peculiarities  in,  transmitted  only  to  the  same 
sex,  260,  loss  of  secondary  sexual  characters  by  male,  261  ;  Polish, 
origin  of  the  crest  in,  261;  period  of  inheritance  of  characters  by,  269; 
cuckoo,  270;  development  of  the  comb  in,  270;  numerical  proportion 
of  the  sexes  in  280 ,  courtship  of,  473  ;  mongrel,  between  a  black 
Spanish  cock  and  different  hens,  485,  penciled  Hamburg,  difference 
of  the  sexes  in,  509,  Spanish,  sexual  differences  of  the  comb  in,  509; 
spurred,  in  both  sexes,  511 


744  INDEX. 

Fox,  W.  D.,  on  some  lialf -tamed  wild  ducks  becoming  polygamous 
and  on  polygamy  in  the  guinea  fowl  and  canary-bird,  249;  on  the 
proportion  of  the  sexes  in  cattle,  280  ;  on  the  pugnacity  of  the  pea- 
cock, 413;  on  a  nuptial  assembly  of  magpies,  461  ;  on  the  finding  of 
new  mates  by  crows,  463,  on  partridges  living  in  triplets,  465;  on  the 
pairing  of  a  goose  with  a  Chinese  gander,  471. 

Foxes,  wariness  of  young,  in  hunting  districts,  90;  black.  616. 

Fraser,  C,  on  the  diiferent  colors  of  the  sexes  in  a  species  of 
SquUla,  306,  Fraser,  G.,  colors  of  lyiecla,  353. 

Frere,  Hookham,  quoting  Theognis  on  selection  in  mankind,  33. 

Fringilla  canabina,  447,  fHngiUa  ciris,  age  of  mature  plumage  in, 
551;  fringilla  cyanea,  age  of  mature  plumage  in,  551  ;  fnngilla 
leucophrys,  young  of,  553;  fiingilla  spinus,  472;  fringilla  tnatis, 
change  of  color  in,  in  spring,  446;  young  of,  553. 

Fringillidae,  resemblance  of  the  females  of  distinct  species  of,  535. 

Frog,  bright  colored  and  distasteful  to  birds,  396. 

Frogs,  395;  male,  temporary  receptacles  for  ova  possessed  by,  235; 
ready  to  breed  before  the  females,  240;  fighing  of,  396;  vocal  organs 
of,  397. 

Frontal  bone,  persistance  of  the  suture  in,  44. 

Fruits,  poisonous,  avoided  by  animals,  75. 

Fuegians,  150,  163;  difference  of  stature  among  the,  35;  power  of 
sight  in  the,  38;  skill  of,  in  stone  throwing,  55;  resistance  of  the, 
to  their  severe  climate,  71,  207,  mental  capacity  of  the,  73;  quasi- 
religious  sentiments  of  the,  107;  resemblance  of,  in  mental  charac 
ters,  to  Europeans,  203;  mode  of  life  of  the,  224;  aversion  of,  to  hair 
on  the  face,  662;  said  to  admire  European  women,  664. 

Fulgoridae,  songs  of  the,  319. 

Fur,  whiteness  of,  in  arctic  animals  in  winter,  260. 

Fur-bearing  animals,  acquired  sagacity  of,  90. 

Gallicrex,  sexual  difference  in  the  color  of  the  irides  in,  483;  galli- 
crex  ciistatiis,  pugnacity  of  male,  409;  red  caruncle  occurring  in  the 
male  during  the  breeding-season,  442. 

Uallinaceae,  frequency  of  polygamous  habits  and  of  sexual  differ- 
ences in  the,  248,  love  gestures  of,  432;  decomposed  feathers  in,  437; 
stripes  of  young,  529,  comparative  sexual  differences  between  the 
species  of,  536,  plumage  of,  537. 

Gallinaceous  birds,  weapons  of  the  male,  412;  racket-shaped  feath- 
ers on  the  heads  of,  436. 

Oallinula  cJUoi'pus,  pugnacity  of  the  male,  409. 

Galloperdix,  spurs  of,  413;  development  of  spurs  in  the  female, 
512. 

OaUopham,  young  of,  533. 

Galls.  68. 

'Gallus  hankiva,  neck-hackles  of,  445;  gaUus  stanleyi,  pugnacity  of 
the  male,  412. 

Galton,  Mr.,  on  hereditary  genius,  31;  gregariousness  and  inde- 
pendence in  animals,  118;  on  the  struggle  between  the  social  and 
personal  impulses,  141;  on  the  effects  of  natural  selection  on  civilized 
nations,  151;  on  the  sterility  of  sole  daughters,  153;  on  the  degree 
of  fertility  of  people  of  genius,  154;  on  the  early  marriages  of  the 
poor,  156;  on  the  ancient  Greeks,  159;  on  the  Middle  Ages,  160;  on 
the  progress  of  the  U.  S.,  161;  on  S.  African  notions  of  beauty,  661. 


INDEX.  745 

Oammarus,  nse  of  the  chelse  of,  303;  gammarus  tnarinMS,  305. 

Gannets,  white  only  when  mature,  SlSO. 

Ganoid  fishes,  180,  187. 

Gaour,  horns  of  the,  576. 

Gap  between  man  and  the  apes,  177. 

Gaper,  sexes  and  young  of,  553. 

Gardner,  on  an  example  of  rationality  in  a  GekuimuSy  305. 

Garrulus  gUindariu«,  463. 

Gartner,  on  sterility  of  hybrid  plants,  196. 

Gasteropoda,  297.  pulmoniferous,  courtship  of,  297. 

GanUrotieuiy  249,  nidification  of,  391;  gcuierosUug  leiurus,  376, 
386,  391;  gasterosteus  tracJiurus,  376. 

GaMropfiora,  wings  of,  brightly  colored  beneath,  357. 

Gauchos,  want  of  humanity  among  the,  139. 

Gaudry,  M.,  on  a  fossil  monkey,  175. 

Gatfia,  seasonal  change  of  plumage  in,  561. 

Geese,  clanging  noise  made  by,  418,  pairing  of  different  species  of, 
471;  Canada,  selection  of  mates  by,  471,  473. 

Gegenbaur,  C,  on  the  number  of  digits  in  the  Ichthyopterygia, 
42,  on  the  hermaphroditism  of  the  remote  progenitors  of  the  verte- 
brata,  183;  two  types  of  nipple  in  mammals,  184. 

Gelcuimug,  proportions  of  the  sexes  in  a  species  of,  288;  use  of  the 
enlarged  chelae  of  the  male,  303;  pugnacity  of  males  of,  305; 
rational  actions  of  a,  305;  difference  of  color  in  the  sexes  of  a  species 
of,  307. 

Gemmules,  dormant  in  one  sex,  261. 

Genius,  31 ;  hereditary,  643,  644,  fertility  of  men  and  women  of, 
154. 

Geoffrey- Saint-Hilaire,  Isid.,  on  the  recognition  of  women  by  male 
quadrumana,  9 ;  on  monstrosities,  33 ;  coincidences  of  arrested 
development  with  polydactylism,  42;  on  animal-like  anomalies  in  the 
human  structure,  45;  on  the  correlation  of  monstrosities,  49;  on  the 
distribution  of  hair  in  man  and.monkeys,  64;  on  the  caudal  vertebrae 
of  monkeys,  65;  on  correlated  variability,  68;  on  the  classification  of 
man,  167;  on  the  long  hair  on  the  heads  of  species  of  Semnopitheeus, 
171;  on  the  hair  in  monkeys,  172,  on  the  development  of  horns  in 
feuiale  deer.  574;  and  F.  Cuvier,  on  the  mandrill,  614;  on  Hylobates, 
636,637 

Geographical  distribution,  as  evidence  of  specific  distinctions  in 
man,  192. 

Geometrae,  brightly  colored  beneath.  357. 

Geophagus,  frontal  protuberance  of  male,  385.  392;  ^;gs  hatched 
by  the  male,  in  the  mouth  or  branchial  cavity,  392. 

Georgia,  change  of  color  in  Germans  settled  in,  223. 

Geotrupes,  stridulation  of,  343,  345. 

Gerbe,  M.,  on  the  nest-building  of  Crenilabus  nuuaa  and  C.  mdopt 
391. 

Gerland,  Dr.,  on  the  prevalence  of  infanticide,  132,  659,  676;  on 
the  extinction  of  races,  207. 

Gervais,  P.,  on  the  hairiness  of  the  gorilla,  64;  on  the  mandrill, 
614. 

Gesture  language,  203. 

Ghost-moth,  sexual  difference  of  color  in  the,  358. 


746  INDEX. 

Giard,  M.,  disputes  descent  of  vertebrates  from  Ascidians,  182, 
color  of  sponges  and  Ascidians,  295;  musky  odor  of  Sphinx,  849. 

Gibbon,  voice  of,  602,  647. 

Gibbon,  Hoolock,  nose  of,  171. 

Gibbs,  Sir  D.,  on  differences  of  the  voice  indifferent  races  of  men, 
646. 

Gill,  Dr.,  male  seals  larger  than  females,  247;  sexual  differences 
in  seals,  588. 

Giraffe,  its  mode  of  using  the  horns,  580;  mute,  except  in  the  rut- 
ting season,  600. 

Giraud  Teulon,  on  the  cause  of  short  sight,  38. 

Glanders,  communicable  to  man  from  the  lower  animals,  7. 

Glands,  odoriferous,  in  mammals,  604,  605. 

Qlareola,  double  moult  in,  442. 

Glomeris  limbata,  difference  of  color  in  the  sexes  of,  310. 

Glow-worm,  female  apterous,  235;  luminosity  of  the,  314. 

Gnants,  dances  of,  318;  auditory  powers  of,  648. 

Gnu,  skeletons  of,  found  locked  together,  571;  sexual  differences 
in  the  color  of  the,  612. 

Goat,  male,  wild,  falling  on  his  horns,  579;  male,  odor,  emittted 
by,  604;  male,  wild  crest  of  the,  608;  Berbura,  mane,  dewlap,  etc., 
of  the  male,  608;  Kemas,  sexual  difference  in  the  color  of  the,  612. 

Goats,  sexual  differences  in  the  horns  of,  260;  horns  of,  266;  mode 
of  fighting  of,  579;  domestic,  sexual  differences  of,  late  developed, 
269;  beards  of,  606. 

Goatsucker,  Virginian,  pairing  of  the,  416. 

Gobies,  nidification  of,  391. 

God,  want  of  the  idea  of,  in  some  races  of  men,  105. 

Godron  M.,  on  variability,  33;  on  difference  of  stature,  35;  on  the 
want  of  connection  between  climate  and  the  color  of  the  skin,  219; 
on  the  color  of  the  skin,  225;  on  the  color  of  infants.  636. 

Goldfinch,  421,  446;  proportion  of  the  sexes  in  the,  281;  sexual 
differences  of  the  beak  in  the,  409;  courtship  of  the,  455;  North 
American,  young  of,  553. 

Goldfish.  388,  389. 

Oomphus,  proportions  of  the  sexes  in,  287;  difference  in  the  sexes 
of,  328. 

Oonepteryx  Rhamni,  354,  sexual  difference  of  color  in,  365. 

Goodsir,  Prof.,  on  the  affinity  of  the  lancelet  to  the  ascidians,  181. 

Goosander,  young  of,  532. 

Goose,  Antarctic,  colors  of  the,  560;  Canada,  pairing  with  a  Ber- 
nicle  gander,  471;  Chinese,  knob  on  the  beak  of  the,  484;  Egyptian, 
414;  Sebastopol,  plumage  of,  438;  snow,  whiteness  of  the,  561;  spur- 
winged,  414. 

(ilorilla,  640;  semi-erect  attitude  of  the,  58;  mastoid  processes  of 
the,  59;  protecting  himself  from  the  rain  with  his  hands,  172;  manner 
of  sitting,  172;  supposed  to  be  a  kind  of  mandrill,  202;  polygamy  of 
the,  245,  647,  675;  voice  of  the,  602;  cranium  of,  636;  fighting  of 
male,  641. 

Gosse,  P.  H.,  on  the  pugnacity  of  the  male  humming-bird,  409; 
Gosse,  M.,  on  the  inheritance  of  artificial  modifications  of  the  skull, 
689. 

Gould,  B.  A.,  on  variation  in  the  length  of  the  legs  in  man,  29; 


INDEX.  74'J' 

liieastirements  of  American  soldiers,  34,  36;  on  the  proportions  of 
the  body  and  capacity  of  the  lungs  in  different  races  of  men,  190;  on 
the  inferior  vitality  of  mulattoes,  195;  Gould,  J.,  on  migration  of 
swifts,  122;  on  the  arrival  of  male  snipes  before  the  females,  240; 
on  the  numerical  proportion  of  the  sexes  in  birds,  280;  on  Neomorpha 
Chrypus,  408;  on  the  species  of  Eustepliamts,  408;  on  the  Australian 
musk-duck,  468;  on  the  relative  size  of  the  sexes  in  Briziura  Idbata 
and  Cindoramphus  cruralis,  411;  on  Lobivanellus  lobatus,  414;  on 
the  habits  of  Menura  Alberti,  421 ;  on  the  rarity  of  song  in  brilliant 
birds,  421;  on  Selasphorvs  platycercus,  429;  on  the  bower-birds,  432, 
461;  on  the  ornamental  plumage  of  the  humming-birds,  440;  on  the 
moulting  of  the  ptarmigan,  444;  on  the  display  of  plumage  by  the 
male  humming-birds,  447;  on  the  shyness  of  adorned  male  birds,  456; 
on  the  decoration  of  the  bowers  of  bower-birds,  469;  on  the  decora- 
tion of  their  nests  by  humming-birds,  469;  on  variation  in  the  genus 
Cynanthns,  481;  on  the  color  of  the  thighs  in  a  male  paroquet,  481; 
on  Urosticte  Benjamini,  502  et  seq.;  on  the  nidifi cation  of  the  Orioles, 
516;  on  obscurely  colored  birds  building  concealed  nests,  516;  on 
trogons  and  kingfishers,  520;  on  Australian  parrots,  521;  on  Austral- 
ian pigeons,  522;  on  the  moulting  of  the  ptarmigan,  526;  on  the  im- 
mature plumage  of  birds,  530  et  seq.;  on  the  Australian  species  of 
Turnix,  542;  on  the  young  of  A'ithurus  polytmus,  555;  on  the  colors 
of  the  bills  of  toucans,  560;  on  the  relative  size  of  the  sexes  in  the 
marsupials  of  Australia,  588;  on  the  colors  of  the  marsupials,  609. 

Goureaux,  on  the  stridulation  of  MutiUa  europcm,  332. 

Gout,  sexually  transmitted,  268. 

Graba,  on  the  Pied  Ravens  of  the  Feroe  Islands,  482;  variety  of 
the  Guillemot,  482. 

Gradation  of  secondary  sexual  characters  in  birds,  488. 

Grallatores,  absence  of  secondary  sexual  characters  in,  248; 
double  moult  in  some,  443. 

GraUina,  nidification  of,  517. 

Grasshoppers,  stridulation  of  the,  324. 

Gratiolet,  Prof.,  on  the  anthropomorphous  apes,  175;  on  the  evolu- 
tion of  the  anthropomorphous  apes,  202;  on  the  difference  iu  the  de- 
velopment of  the  brains  of  apes  and  man,  231. 

Gray,  Asa,  on  the  gradation  of  species  among  the  Compositae,  199; 
Gray,  J.  E.,  on  the  caudal  vertebrae  of  monkeys,  65;  on  the  presence 
of  rudiments  of  horns  in  the  female  of  Cerfj^us  moschatus,  574;  on 
the  horns  of  goats  and  sheep,  575;  on  crests  of  male  antelopes,  606; 
on  the  beard  of  the  ibex,  607;  on  the  Berbura  goat,  608;  on  sexual 
differences  in  the  coloration  of  rodents,  609;  ornaments  of  male  sloth, 
610;  on  the  colors  of  the  Elands,  611;  on  the  sing-sing  antelope,  612; 
on  the  colors  of  goats,  612;  on  Lemur  Macaco,  613;  on  the  hog-deer, 
623. 

"Greatest  happiness  principle,"  135,  136. 

Greeks,  ancient,  159. 

Green,  A.  H,,  on  beavers  fighting,  570;  on  the  voice  of  the 
beaver,  602. 

Greenfinch,  selected  by  a  female  canary,  472. 

Greg,  W.  R.,  on  the  effects  of  natural  selection  on  civilized  nations, 
151;  on  the  early  marriages  of  the  poor,  156;  on  the  ancient  Greeks, 
159. 


74B  iZVD^X 

Grenadiers,  Prussian,  32. 

Greyhounds,  numerical  proportion  of  tlie  sexes  in,  244;  numerical 
proportion  of  male  and  female  births  in,  278,  291. 

Grouse,  red,  monogamous,  248;  pugnacity  of  young  male,  414;  pro- 
ducing a  sound  by  beating  their  wings  together,  416;  duration  of 
courtship  of,  460;  colors  and  nidification  of,  518. 

Gruber,  Dr.,  on  the  occurrence  of  the  supra-condyloid  foramen  in 
the  humerus  of  man,  23;  on  division  of  malar  bone,  44;  stridulation 
of  locust,  322;  ephippiger,  326. 

Grus  Americanus,  age  of  mature  plumage  in,  551,  breeding  in  im- 
mature plumage,  552;  grus  mrgo,  trachea  of,  425. 

Oryllus  campestris,  321;  pugnacity  of  male,  327;  gryllus  domes- 
ticus,  322 

Grypus,  sexual  differences  in  the  beak  in,  408. 

Guanacoes,  battles  of,  570;  canine  teeth  of,  580. 

Guanas,  strife  for  women  among  the,  641;  polyandry  among  the 
677. 

Guanche  skeletons,  occurrence  of  the  supra-condyloid  foramen  in 
the  humerus  of,  24. 

Guaranys,  proportion  of  men  and  women  among,  276;  color  of 
new-born  children  of  the,  636;  beards  of  the,  639. 

Guenee,  A.,  on  the  sexes  of  Hyperythra,  283. 

Guilding,  L.,  on  the  stridulation  of  the  locustidae,  320. 

Guillemot,  variety  of  the,  482. 

Guinea,  sheep  of,  with  males  only  horned,  266. 

Guinea-fowl,  monogamous,  248;  occasional  polygamy  of  the,  249; 
markings  of  the,  488. 

Guinea-pigs,  inheritance  of  the  effects  of  operations  by,  67. 

Gulls,  seasonal  change  of  plumage  in,  560;  white,  560. 

Giinther,  Dr.,  on  paddle  of  Ceratodus,  42;  on  hermaphroditism  in 
Serranus,  184;  on  male  fishes  hatching  ova  in  their  mouths,  185, 
391 ;  on  mistaking  infertile  female  fishes  for  males,  281 ;  on  the  pre- 
hensile organs  of  male  Plagiostomous  fishes,  37;  spines  and  brushes 
on  fishes,  37;  on  the  pugnacity  of  the  male  salmon  and  trout,  377; 
on  the  relative  size  of  the  sexes  in  fishes,  380;  on  sexual  differences 
in  fishes,  381;  et  seq.;  on  the  genus  Callionymus,  381;  on  a  protec- 
tive resemblance  of  pipe-fish,  390;  on  the  genus  of  Solenostoma,  392; 
on  the  coloration  of  frogs  and  toads,  396;  combat  of  Testudo  elegans, 
398;  on  the  sexual  differences  in  the  Ophidia,  399;  on  differences  of 
the  sexes  of  lizards,  402  et  seq. 

Gynanisa  Ms,  ocellated  spots  of,  486. 

Gypsies,  uniformity  of,  in  various  parts  of  the  world,  220. 

Habits,  bad,  facilitated  by  familiarity,  139;  variability  of  the  force 
of,  142. 

Hackel,  E.,  on  the  origin  of  man,  3;  on  rudimentary  characters,  12; 
on  death  caused  by  inflammation  of  the  vermiform  appendage,  23;  on 
the  canine  teeth  in  man,  45;  on  the  steps  by  which  man  became  a 
biped,  58;  on  man  as  a  member  of  the  Catarrhine  group,  176;  on  the 
position  of  the  Lemuridae,  178;  on  the  genealogy  of  the  Mammalia, 
179;  on  the  lancelet,  181;  on  the  transparency  of  pelagic  animals, 
295;  on  the  musical  powers  of  women,  653. 

Hagen,  H.,  and  Walsh,  B.  D.,  on  American  Nueroptera,  286. 

Hair,  development  of,  in  man,  20;  character  of,  supposed   to  be 


INDEX.  749 

determined  by  liglit  and  lieat,  36;  distribution  of,  in  man,  63,  685; 
possibly  removed  for  ornamental  purposes.  65;  arrangement  and  direc- 
tion of'  171;  of  the  early  progenitors  of  man,  182;  different  texture 
of,  in  distinct  races,  190;  and  skin  correlation  of  color  of,  225;  devel- 
opment of,  in  mammals,  606 ;  management  of,  among  different 
peoples,  655;  great  length  of,  in  some  North  American  tribes,  662; 
elongation  of  the,  on  the  human  head,  689;  possible  inherited  effect 
of  plucking  out,  689. 

Hairiness,  difference  of,  in  the  sexes  in  man,  637;  variation  of,  in 
races  of  men,  637. 

Hairs  and  excretory  pores,  numerical  relation  of,  in  sheep,  225. 

Hairy  family,  Siamese,  687. 

Halbertsma,  Prof.,  hermaphroditism  in  Serranus,  184. 

Hamadryas  baboon,  turning  over  stones,  114;  mane  of  the  male,  594. 

Hamilton,  C,  on  the  cruelty  of  the  KaflBrsto  animals,  133;  on  the 
engrossment  of  the  women  by  the  Kaffir  chiefs,  680. 

Hammering,  difficulty  of,  55. 

Hancock,  A.,  on  the  colors  of  nudibranch  Mollusca,  296,  298. 

Hands,  larger  at  birth,  in  the  children  of  laborers,  37;  structure  of, 
in  the  quadrumana,  56;  arms,  freedom  of,  indirectly  correlated  with 
dimunition  of  canines,  60. 

Handwriting,  inherited,  100. 

Handyside,  Dr. ,  supernumery  mammae  in  men,  42. 

Harcourt,  E.  Vernon,  on  FHiigilla  camiabina,  447. 

Hare,  protective  coloring  of  the,  619. 

Harelda  glacialis,  478. 

Hares,  battles  of  male,  570. 

Harlan,  Dr.,  on  the  difference  between  field  and  house-slaves,  224. 

Harris,  J.  M.,  on  the  relation  of  complexion  to  climate,  222;  Harris, 
T.  W.,  on  the  Katydid  locust,  321;  on  the  stridulation  of  the  grass- 
hoppers, 324;  on  (Ecanthus  nivalis,  328  ;  on  the  coloring  of  Lepi- 
doptera,  356;  on  the  coloring  of  Saturnia  lo,  358. 

Harting,  spur  of  the  Omithorhynchus,  573. 

Hartman,  Dr. ,  on  the  singing  of  Cicada  septendecim,  319. 

Hatred,  persistence  of,  127. 

Haughton,  S.,  on  a  variation  of  the  Jlexo?' poUicis  long  us,  in  man,  48. 

Hawks,  feeding  orphan  nestling,  465. 

Hayes,  Dr.,  on  the  diverging  of  sledge-dogs  on  thin  ice,  85. 

Haymond,  R.,  on  the  drumming  of  the  male  Tetrao  ujnbellus,  426; 
on  the  drumming  of  birds,  427. 

Head,  altered  position  of,  to  suit  the  erect  attitude  of  man,  62; 
hairiness  of,  in  man,  64;  processes  of,  in  male  beetles,  334;  artificial 
alterations  of  the  form  of  the,  664. 

Hearne,  on  strife  for  women  among  the  North  American  Indians, 
640;  on  the  North  American  Indians'  notion  of  beauty,  659;  repeated 
elopements  of  a  North  American  woman,  682. 

Heart,  in  the  human  embryo,  10. 

Heat,  supposed  effects  of,  36. 

Hectocotyle,  298. 

Hedge- warbler,  539;  young  of  the,  548. 

Heel,  small  projection  of,  in  the  Aymara  Indians,  39. 

Hegt,  M,,  on  the  development  of  the  spurs  in  peacocks,  267. 

Heliconidae,  350;  mimicry  of,  by  other  butterflys,  366. 


750  INDEX. 

Heliopathes,  stridulation  ])eculiar  to  the  male,  345. 

Heliothrix  uuriculata,  young  of,  532,  583. 

JJelix  pomatidy  example  of  individual  attachment  in,  297. 

Hellins,  J . ,  pio])ortions  of  sexes  of,  Lepido])tera  reared  by,  285. 

Hemboltz,  on  pleasure  derived  from  harmonies,  104;  on  the  human 
eye,  501;  on  the  vibration  of  the  auditory  hairs  of  Crustacea,  649; 
the  physiology  of  harmony,  649. 

Hemiptera,  318. 

Hemitraguif,  beardless  in  both  sexes,  607. 

Hemsbach,  M.  von,  on  medial  mamma  in  man,  42. 

Hen,  clucking  of,  418. 

Hepburn,  Mr.,  on  the  autumn  song  of  the  water-ouzel,  420. 

Hepialus  humuli,  sexual  difference  of  color  in  the,  358. 

Herbs,  poisonous,  avoided  by  animals,  75. 

Hermaphroditism,  of  embryos,  183;  in  fishes,  184. 

Herodias  bubulcus,  vernal  moult  of,  445. 

Heron,  Sir  R.,  on  the  habits  of  pea-fowl,  475,  477,  503. 

Herons,  love-gestures  of,  331;  decomposed  feathers  in,  437;  breed- 
ing plumage  of,  443,  444;  young  of  the,  548,  553,  sometimes  dimor- 
phic, 552;  continued  growth  of  crest  and  plumes  in  the  males  of 
some,  552;  change  of  color  in  some,  562. 

Hesperomys  cognatus,  648. 

Hetoerina,  proportion  of  the  sexes  in,  287;  difference  in  the  sexes 
of,  328. 

Heterocerus,  stridulation  of,  842. 

Hewitt,  Mr.,  on  a  game  cock  killing  a  kite,  412;  on  the  recognition 
of  dogs  and  cats  by  ducks,  468;  on  the  pairing  of  a  wild  duck  with  a 
pintail  drake,  471;  on  the  courtship  of  fowls,  478;  on  the  coupling 
of  pheasants  with  common  hens,  477. 

Hilgendorf ,  sounds  produced  by  crustaceans,  309. 

Hindoo,  his  horror  of  breaking  his  caste,  138,  140. 

Hindoos,  local  differences  of  stature  among,  35;  difference  of,  from 
Europeans,  218;  color  of  the  beard  in,  637. 

IlippareJda  Jamra,4SS;  instability  of  the  ocellated  spots  of,  486. 

Hippocampus,  development  of,  185;  marsupial  receptacles  of  the 
male,  392;  1iij)j)ocampus  minor,  227,  230. 

Hippopotamus,  nakedness  of,  68. 

Hips,  proportions  of,  in  soldiers  and  sailors,  36. 

Hodgson,  S.,  on  the  sense  of  duty.  111. 

Hoffberg,  on  the  horns  of  the  reindeer,  574;  on  sexual  preferences 
shown  by  reindeer,  598. 

Hoffman,  Prof.,  protective  colors,  318;  fighting  of  frogs,  396. 

Hog,  wart,  592;  river,  593. 

Hog-deer,  623. 

Holland,  Sir  H. ,  on  the  effects  of  new  diseases,  208. 

Homologous  structures,  correlated  variation  of,  49. 

Homoptera,  319;  stridulation  of  the,  and  Orthoptera,  discussed,  327. 

Honduras,  Quiscalus  major  in,  281. 

Honey-buzzard  of  India,  variation  in  the  crest  of,  481. 

Honey-sucker,  females  and  young  of,  533. 

Honey-suckers,  moulting  of  the,  444;  Australian,  nidification  of ,  516. 

Honor,  law  of,  137. 

Hooker,  Dr.,  forbearance  of  elephant  to  his  keeper,  117;  on  the 
color  of  the  beard  in  man,  637. 


INDEX,  751 

Hookham,  Mr.,  on  mental  concepts  in  animals,  94. 

Hoolock  Gibbon,  nose  of,  171. 

Hoopoe,  421;  sounds  produced  by  male,  427. 

Hoplopterns  annatus,  wing-spurs  of,  414. 

Horn  bill,  African,  inflation  of  the  neck- wattle  of  the  male  during 
courtship,  435. 

Hornbills,  sexual  difference  in  the  color  of  the  eyes  in,  483;  nidfica- 
tion  and  incubation  of,  516. 

Home,  C,  on  the  rejection  of  a  brightly  colored  locust  by  lizards 
and  birds,  428. 

Horns,  sexual  differences  of,  in  sheep  and  goats,  260;  loss  of,  in 
female  merino  sheep,  261  ;  development  of,  in  deer,  264 ;  devel- 
opment in  antelopes,  265;  from  the  head  and  thorax,  in  male  beetles, 
336;  of  deer,  573,  577,  587;  originally  a  masculine  character  in  sheep, 
576,  and  canine  teeth,  in  versed  development  of,  586. 

Horse,  fossil,  extinction  ol  the,  in  South  America,  218;  polygamous, 
246;  canine  teeth  of  male,  572;  winter  change  of  color,  619. 

Horses,  rapid  increase  of,  in  South  America,  53;  diminution  of 
canine  teeth  in,  60  ;  dreaming.  84  ;  of  the  Falkland  Islands  and 
Pampas,  206;  numerical  proportion  of  the  sexes  in,  244,  245;  lighter 
in  winter  in  Siberia,  260;  sexual  preferences  in,  598;  pairing  preferently 
with  those  of  the  same  color  617;  numerical  proportion  of  male  and 
female  births  in,  278;  formerly  striped,  626. 

H^)ttentot  women,  peculiarities  of,  198. 

Hottentots,  lice  of,  192;  readily  become  musicians,  650;  notions  ct 
female  beauty  of  the,  660;  compression  of  nose  by,  665. 

Hough,  Dr.  S.,  men's  temperature  more  variable  than  women's, 
253,  proportion  of  sexes  in  man,  274. 

House-slaves,  difference  of,  from  field-slaves,  224. 

Houzeau,  on  the  baying  of  the  dog,  84;  on  reason  in  dogs,  84; 
birds  killed  by  telegraph  wires,  90;  on  the  cries  of  domestic  fowls 
and  parrots,  96,  99;  animals  feel  no  pity,  116;  suicide  in  the  Aleutian 
islands,  133. 

Howorth,  H.  H,,  extinction  of  savages,  209. 

Huber,  P.,  on  ants  playing  together,  77;  on  memory  in  ants,  83; 
on  the  intercommunication  of  ants,  101;  on  the  recognition  of  each 
other  by  ants  after  separation,  331. 

Hue,  on  Chinese  opinions  of  the  appearance  of  Europeans,  659. 

Huia,  the,  of  New  Zealand,  236. 

Human,  man  classed  alone  in  a,  kingdom,  167;  sacrifices,  108. 

Humanity,  unknown  among  some  savages,  133 ;  deficiency  of, 
among  savages,  139. 

Humboldt,  A.  von,  on  the  rationality  of  mules,  88;  on  a  parrot 
preserving  the  language  of  a  lost  tribe,  206;  on  the  cosmetic  arts  of 
savages,  ^4;  on  the  exaggeration  of  natural  characters  by  man,  664; 
on  the  red  painting  of  American  Indians,  665. 

Hume,  D.,  on  sympathetic  feelings,  123. 

Humming-bird,  racket-shaped  feathers  in  the  tail  of  a,  436;  dis 
play  of  plumage  by  the  male,  447. 

Humming-birds,  ornament  their  nests,  104,  469;  polygamous,  248; 
proportion  of  the  sexes  in,  281,  555;  sexual  differences  in,  408,  503; 
pugnacity  of  male,  409;  modified  primaries  of  male,  429;  coloration 
of  the  sexes  of,  440;  display  by.  503;  niditicatioo  of  til©,  516,  517; 
colors  of  female,  5X0;  youxig  of, '555. 


762'  INDEX. 

Humor,  sense  of,  in  dogs,  80. 

Humphreys,  H.  N  ,  on  the  habits  of  the  stickleback,  249,  376* 

Hunger,  instinct  of,  127. 

Huns,  ancient,  flattening  of  the  nose  by  the,  665. 

Hunter,  J.,onthenumberof  species  of  man,  199;  on  secondary  sexual 
characters,  234;  on  the  general  behavior  of  female  animals  during 
courtship,  251;  on  the  muscles  of  the  larynx  in  song-birds,  421;  on 
strength  of  males,  588;  on  the  curled  frontal  hair  of  the  bull,  606;  on 
the  rejection  of  an  ass  by  a  female  zebra,  617. 

Hunter,  W.  W.,  on  the  recent  rapid  increase  of  the  Santali,  51;  on 
the  Santali,  218. 

Huss,  Dr.  Max,  on  the  mammary  glands,  184. 

Hussey,  Mr.,  on  a  partridge  distinguishing  persons,  468. 

Hutchinson,  Col.,  example  of  reasoning  in  a  retriever,  88. 

Hutton,  Capt.,  on  the  male  wild  goat  falling  on  his  horns,  579. 

Huxley,  T.  H.,  on  the  structural  agreement  of  man  with  the  apes, 
2;  on  the  agreement  of  the  brain  in  man  with  that  of  lower  animals, 
6;  on  the  adult  age  of  the  oraftg,  9;  on  the  embryonic  development 
of  man,  10;  on  the  origin  of  man,  3,  12;  on  variation  in  the  skulls  of 
the  natives  of  Australia,  29.  on  the  abductor  of  the  fifth  metatarsal  in 
apes,  47;  on  the  nature  of  the  reasoning  power,  87;  on  the  position 
of  man,  176;  on  the  suborders  of  primates,  173;  on  the  Lemuridae, 
179;  on  the  Dinosauria,  180;  on  the  amphibian  affinities  of  the  Ich- 
thyosaurians,  180;  on  variability  of  the  skull  in  certain  races  of  man, 
198;  on  the  races  of  man,  201;  supplement  on  the  brain,  227. 

Hybrid  birds,  production  of,  470. 

Hydrophobia  communicable  between  man  and  the  lower  animals,  7. 

HydroporuSy  dimorphism  of  females  of,  313. 

Hyelaphus  j)orcinnSy  623. 

HygrogonuSy  392. 

Hyla,  singing  species  of,  397. 

Uylohates,  absence  of  the  thumb  in,  57;  upright  progression  of 
some  species  of,  59;  maternal  affection  in  a,  79;  direction  of  the  hair 
on  the  arms  of  species  of,  172;  females  of.  less  hairy  below  than 
males,  637;  hylobates  agilis,  57;  hair  on  the  arms  of,  172;  musical 
voice  of,  602,  superciliary  ridge  of,  636;  voice  of,  647. 

Hylobates  hoolock,  sexual  difference  of  color  in,  613;  hylobates  lar, 
57;  hair  on  the  arms  of,  72;  female  less  hairy,  637;  hylobates  leucis- 
cus,  57;  song  of,  647;  hylobates  syndactylus,  57;  laryngeal  sac  of,  602. 

Hylophila  prasinana,  349. 

Hymenoptera,  330;  large  size  of  the  cerebral  ganglia  in,  437; 
classification  of,  168;  sexual  differences  in  the  wings  of,  314;  aculeate, 
relative  size  of  the  sexes  of,  316. 

Hymenopteron,  parasitic,  with  a  sedentary  male,  251. 

Hyomoschus  aquaticus,  624. 

Hyperythra,  proportion  of  the  sexes  in,  283. 

Hypogymna  dispar,  sexual  difference  of  color  in,  358. 

Hypopyra,  coloration  of,  357. 

Ibex,  male,  falling  on  his  horns,  579;  beard  of  the,  607. 

Ibis,  white,  change  of  color  of  naked  skin  in,  during  the  breeding 
season,  442;  scarlet,  young  of  the,  548;  ibis  tantalus,  age  of  mature 
plumage  in,  551;  breeding  in  immature  plumage,  552. 


INDEX.  753 

Ibisis,  decomposed  feathers  in,  487;  white,  560;  and  black,  562. 

Ichneumonidae,  difference  of  the  sexes  in,  331. 

Ichthyopterygiay  42. 

Ichthjosaurians,  180. 

Idiots,  microcephalous,  their  characters  and  habits,  40;  hairiness 
and  animal  nature  of  their  actions,  41;  microcephalous  imitative 
faculties  of,  98. 

Jguuna  tuberculata,  402. 

Iguanas,  402. 

Illegitimate  and  legitimate  children,  proportion  of  the  sexes  in,  276. 

Imagination,  existence  of,  in  animals,  84. 

Imitation,  77;  of  man  by  monkeys,  82;  tendency  to,  in  monkeys, 
microcephalous  idiots  and  savages,  98;  influence  of,  146. 

Immature  plumage  of  birds,  528,  531. 

Implacentata,  179. 

Implements,  employed  by  monkeys,  91;  fashioning  of,  peculiar  to 
man,  92. 

Impregnation,  period  of,  influence  of,  upon  sex,  277. 

Improvement,  progressive,  man  alone  suppposed  to  be  capable 
of,  89. 

Incisor  teeth,  knocked  out  or  filed  by  some  savages,  656. 

Increase,  rate  of,  50;  necessity  of  checks  in,  53. 

Indecency,  hatred  of,  a  modern  virtue,  135. 

India,  difficulty  of  distinguishing  the  native  races  of,  190; 
Cyprinidae  of,  389;  color  of  the  beard  in  races  of  men  of,  637. 

Indian,  North  American,  honored  for  scalping  a  man  of  another 
tribe,  132. 

Individuality,  in  animals,  93. 

Indolence  of  man,  when  free  from  a  struggle  for  existence,  161. 

Indopicius  carlotta,  colors  of  the  sexes  of,  521. 

Infanticide,  prevalence  of,  52, 132,  289,  290;  supposed  cause  of,  658; 
prevalence  and  causes  of,  675  et  seq. 

Inferiority,  supposed  physical,  of  man,  72. 

Inflammation  of  the  bowels,  occurrence  of,  in  Cebus  Azarw,  7. 

Inheritance,  31;  of  long  and  short  sight,  37;  of  effects  of  use  of 
vocal  and  mental  organs,  100;  of  moral  tendencies,  139,  143;  laws  of 
257;  sexual,  262;  sexually  limited,  506. 

Inquisition,  influence  of  the,  159. 

Insanity,  hereditary,  31. 

Insect,  fossil,  from  the  Devonian,  327. 

Insectivora,  610;  absence  of  secondary  sexual  characters  in,  247. 

Insects,  relative  size  of  the  cerebral  ganglia  in,  60;  male,  appear- 
ance of,  before  the  females,  240;  pursuit  of  female,  by  the  males,  250; 
period  of  development  of  sexual  characters  in,  268 ;  secondary 
sexual  characters  of,  311;  kept  in  cages,  319,  327;  stridulation^646. 

Insessores,  vocal  organs  of,  421. 

Instep,  depth  of,  in  soldiers  and  sailors,  36. 

Instinct  and  intelligence.  75;  migratory,  vanquishing  tlie  maternal, 
122,  128. 

Instinctive  actions,  the  result  of  inheritance,  119;  impulses,  dif- 
ference of  the  force,  125  et  seq.;  and  moral  impulses,  alliance  of,  126. 

Instincts,  74;  complex  origin  of,  through  natural  selection,  76; 
possible  origin  of  some,  76;   acquired,  of  domestic  animals,  118; 


754  INDEX. 

variability  of  the  force  of,  121;  diiference  of  force  between  the 
social  and  other,  l!;^,6,  148;  utilized  for  new  purposes,  651. 

Instruniental  music  of  birds,  425,  480. 

Intellect,  intiuence  of,  in  natural  selection  in  civilized  society,  154. 

Intellectual  faculties,  their  intiuence  on  natural  selection  in  man, 
144;  prol)ably  perfected  through  natural  selection,  140. 

Intelligence,  Mr.  II.  Spencer  on  the  dawn  of,  75. 

Intenii)erance,  no  reproach  among  savages,  135;  its  destructive- 
ness,  155. 

Intoxication  in  monkeys,  7. 

Iphias  f/laucippe,  354. 

Iris,  sexual  difference  in  the  color  of  the,  in  birds,  435,  483. 

Ischio- pubic  muscle,  46. 

Ithaginis  cruentas,  number  of  spurs  in,  413. 

lulus,  tarsal  suckers  of  the  males  of,  310. 

Jackals  learning  from  dogs  to  lark,  82. 

Jack  snipe,  coloration  of  the,  557. 

Jacquinot,  on  the  number  of  species  of  man,  199. 

Jaeger,  Dr.,  length  of  bones  increased  from  carrying  weights,  36; 
on  the  difficulty  of  approaching  herds  of  wild  animals,  114;  male 
silver  pheasant,  rejected  when  his  plumage  was  spoiled,  476. 

Jaguars,  black,  616. 

Janson,  E.  W.,  on  the  proportions  of  the  sexes  in  Tomicus  vUlosus, 
286;  on  stridulant  beetles,  342. 

Japan,  encouragement  of  licentiousness  in,  52. 

Japanese,  general  beardlessness  of  the,  639;  aversion  of  tL.e,  to 
whiskers,  662. 

Jardine,  Sir  W.,  on  the  Argus  pheasant,  436,  457. 

Jarrold,  Dr.,  on  modifications  of  the  skull  induced  by  unnatural 
position,  62. 

Jarves,  Mr.,  on  infanticide  in  the  Sandwich  Islands,  290. 

J  a  vans,  relative  height  of  the  sexes  of,  638;  notions  of  female 
beauty,  661. 

Jaw,  influence  of  the  muscles  of  the,  upon  the  physiognomy  of 
the  apes,  60. 

Jaws,  smaller  proportionately  to  the  extremities,  37;  influence  of 
food  upon  the  size  of,  37;  diminution  of,  in  man,  60;  in  man,  re- 
duced by  correlation,  641. 

Jay,  young  of  the,  548;  Canada,  young  of  the,  549. 

Jays,  new  mates  found  by,  463;  distinguishing  persons,  468. 

Jeffreys,  J.  tiwyn,  on  the  form  of  the  shell  in  the  sexes  of  the 
Gasteropoda,  297;  on  the  influence  of  light  upon  the  colors  of  shells, 
298. 

Jelly-fish,  bright  colors  of  some,  295. 

J«nner,  Dr.,  on  the  voice  of  the  rook,  426;  on  the  finding  of  new 
mates  by  magpies,  462;  on  retardation  of  the  generative  functions  in 
birds,  465. 

Jenyns,  L.,  on  the  desertion  of  their  young  by  swallows,  122;  on 
male  birds  singing  after  the  proper  season,  465. 

Jerdon,  Dr.,  on  birds  dreaming,  84;  on  the  pugnacity  of  the  male 
bulbul,  409;  on  the  pugnacity  of  the  male  Ortygornis  guldris,  412; 
on  the  spurs  of  Oalloperdix,  413;  on  the  habits  of  LobivaneUus,  414; 


INDEX.  755 

on  the  spoonbill,  425;  on  tlie  drumming  of  the  Kali j -pheasant,  426; 
on  Indian  bustards,  429;  on  Otu  ben(/aleHsis,  432;  on  the  ear-tufts  of 
Sypheotides  auritus,  436;  on  the  double  moults  of  certain  birds,  444; 
on  the  moulting  of  the  honeysuckers,  444;  on  the  moulting  of  bustards, 
})lovers  and  drongos,  445;  on  the  spring  change  of  color  in  some 
finches,  447;  on  display  in  uiale  birds,  447;  on  the  display  of  the 
undertail  coverts  by  the  male  bulbul,  456;  on  the  Indian  honey- 
buzzard,  481;  on  sexual  differences  in  the  color  of  the  eyes  of  horn- 
bills,  483,  on  the  markings  of  the  Tragopan  pheasant,  487;  on  the 
nidification  of  the  Orioles,  516;  on  the  niditication  of  the  hornbills, 
517;  on  the  Sultan  yellow-tit,  521;  on  Palceornis  javanicus,  525;  on 
the  immature  plumage  of  birds,  529,  et  seq.;  on  representative 
species  of  birds,  533;  on  the  habits  of  Tarmx,  542;  on  the  continued 
increase  of  beauty  of  the  peacock,  552;  on  coloration  in  the  genus 
Pakeo}'nis,  562. 

Jevons,  W.  S.,  on  the  migrations  of  man,  53. 

Jews,  ancient  use  of  tiiut  tools  by  the,  164;  uniformity  of,  in 
various  parts  of  the  world,  220;  numerical  proportion  of  male  and 
female  births  among  the,  275;  ancient,  tattooing  practiced  by,  655. 

Johnstone,  Lieut.,  on  the  Indian  elephant,  246. 

Jollofs,  fine  appearance  of  the,  670. 

Jones,  Albert,  proportion  of  sexes  of  Lepidoptera,  reared  by,  285. 

Juan  Fernandez,  humming-birds  of,  555. 

Junonia,  sexual  differences  of  coloring  in  species  of,  351. 

Jupiter,  comparison  with  Assyrian  effigies,  663. 

Kaffir  skull,  occurrence  of  the  diastema  in  a,  45. 

Kaffirs,  their  cruelty  to  animals,  133;  lice  of  the,  194;  color  of  the, 
661;  engrossment  of  the  handsomest  women  by  the  chiefs  of  the, 680; 
marriage-customs  of  the,  683. 

Kalij-pheasant,  drumming  of  the  male,  426;  young  of,  533. 

Kallima,  resemblance  of,  to  a  withered  leaf,  353. 

Kalmucks,  general  beardlessness  of,  639;  aversion  of,  to  hairs  on 
the  face,  662. 

Kangaroo,  great  red,  sexual  difference  in  the  color  of,  609. 

Kant,  Imm.,  on  duty,  110;  on  self-restraint,  124;  on  the  number  of 
species  of  man,  199. 

Katy-did,  stridulation  of  the,  321. 

Keen,  Dr.,  on  the  mental  powers  of  snakes,  399. 

Keller,  Dr.,  on  the  difficulty  of  fashioning  stone  implements,  55. 

Kent,  W.  S. ,  elongation  of  dorsal  fin  of  Callionymus  lyra,  382; 
courtship  of  Lithras  mixtiis,  386;  colors  and  courtship  of  (Jantharus 
lineatus,  386. 

Kestrels,  new  mates  found  by,  463. 

Kidney,  one,  doing  double  work  in  disease,  35. 

King,  W.  R.,  on  the  vocal  organs  of  Tetrao  cupido,  423;  on  the 
drumming  of  grouse,  427;  on  the  reindeer,  574;  on  the  attraction  of 
male  deer  by  the  voice  of  the  female,  601. 

King  and  Fitzroy,  on  the  marriage  customs  of  the  Fuegians,  684. 

King-crows,  nidification  of,  516. 

Kingfisher,  421;  racket  shaped  feathers  in  the  tail  of  a,  436. 

Kingfishers,  colors  and  nidification  of  the,  518,  520,  522;  imma- 
ture plumage  of  the,  532,  533;  young  of  the,  548. 

King  Lory,  521;  immature  plumage  of  the,  532. 


756  INDEX. 

Kingsley,  C,  on  the  sounds  produced  by  Umhrina,  394. 

Kirby  and  Spence,  on  sexual  differences  in  the  hni^th  of  the 
snout  in  Curculionidae,  236;  on  the  courtship  of  insects,  250;  on  the 
elytra  of  I)i/tiscn«,  313;  on  peculiarities  in  the  legs  of  male  insects, 
313;  on  the  relative  size  of  the  sexes  in  insects,  316;  on  the  Fulgor- 
idie,  319;  on  the  habits  of  Termites,  330;  on  difference  of  color  in  the 
sexes  of  beetles,  333;  on  the  horns  of  the  male  lamellicorn  beetles, 
336;  on  hornlike  processes  in  male  Curculionidae,  339;  on  the  pug- 
nacity of  the  male  stag-beetle,  339. 

Kite,  killed  by  a  game-cock,  412. 

Knot,  retention  of  winter  plumage  by  the,  444. 

Knox,  R.,  on  the  semilunar  fold,  19;  on  the  occurrence  of  the 
supra-condyloid  foramen  in  the  humerus  of  man,  23;  on  the  features 
of  the  young  Memnon,  192. 

Koala,  length  of  the  coecum  in,  22. 

Kobiiit  ellipdjjrymnus,  proportion  of  the  sexes  in,  280. 

Kolreuter,  on  the  sterility  of  hybrid  plants,  196. 

Koodoo,  development  of  the  horns  of  the,  265;  markings  of  the,  621. 

Koppen,  F.  T.,  on  the  migratory  locust,  320. 

Koraks,  marriage  customs  of,  683. 

Kordofan,  protuberances  artificially  produced  by  natives  of,  655. 

Korte,  on  the  proportion  of  sexes  in  locusts,  287;  Russian  locusts, 
320. 

Kovalevsky,  A.,  on  the  affinity  of  the  Ascidiatothe  Vertebrata,  181. 

Kovalevsky,  W.,  on  the  pugnacity  of  the  male  capercailzie,  412; 
on  the  pairing  of  the  capercailzie,  416. 

Krause,  on  a  convoluted  body  at  the  extremity  of  the  tail  in  a 
Macaeus  and  a  cat,  25. 

Kupffer,  Prof.,  on  the  affinity  of  the  Ascidia  to  the  Vertebrata,  181. 

Labidocera  Darwinii,  prehensile  organs  of  the  male,  301. 

Labrus,  splendid  colors  of  the  species  of,  382,  labrus  mixtus,  sexual 
differences  in,  382,  386;  labrus  pavo,  388. 

Lacertilia,  sexual  differences  of,  401. 

Lafresnaye,  M.  de,  on  birds  of  paradise,  439. 

Lamarck,  on  the  origin  of  man,  3. 

Lamellibranchiata,  296. 

Lamellicorn  beetles,  horn-like  processes  from  the  head  and  thorax 
of,  334,  336;  influence  of  sexual  selection  on,  341. 

Lamellicornia,  stridulation  of,  343. 

Lamont,  Mr.,  on  the  tusks  of  the  vralrus,  572;  on  the  use  of  its 
tusks  by  the  walrus,  585;  on  the  bladder-nose  seal,  603. 

Lampornis  porphyrurus,  colors  of  the  female,  516. 

Lampyridae,  distasteful  to  mammals,  314. 

Lancelot,  181,  187. 

Landois,  H.,  gnats  attracted  by  sound,  318;  on  the  production  of 
sound  by  the  Cicadae,  319;  on  the  stridulating  organ  of  the  crickets, 
321;  on  Decticus,  323;  on  the  stridulating  organs  of  the  Acridiidae, 
324;  stridulating  apparatus  in  Orthoptera,  326;  on  the  stridulation  of 
Necrophorus,  342;  on  the  stridulant  organs  of  Cerambyx  heros,  343; 
on  the  stridulant  organ  of  Oeotritpes,  343;  on  the  stridulating  organs 
in  the  Coleoptera,  344;  on  the  ticking  of  Anobinm,  347. 

Landor,  Dr.,  on  remorse  for  not  obeying  tribal  custom,  130. 

Language,  an  art,  97;   articulate,  origin  of,  98 ;    relation  of  the 


INDEX.  t57 

J)rogress  of,  to  the  development  of  the  brain,  99;  effects  of  inlier 
itance  in  production  of,  100;  complex  structure  of,  among  barbar- 
ous nations,  103;  natural  selection  in,  108;  gesture,  203;  primeval, 
204;  of  a  lost  tribe  preserved  by  a  parrot,  206. 

Languages,  presence  of  rudiments  in,  102;  classification  of,  102; 
variability  of,  102;  crossing  or  blending  of,  102;  complexity  of,  no  test 
of  perfection  or  proof  of  special  creation,  103;  resemblance  of,  evi- 
dence of  community  of  origin,  169;  languages  and  species,  identity 
of  evidence  of  their  gradual  development,  102. 

Lanias,  525;  characters  of  young,  529;  laniiis  rufus,  anomalous 
young  of,  550. 

Lankester,  E.  R.,  on  comparative  longevity,  151,  155;  on  the  de- 
structive effects  of  intemperance,  155. 

Lanugo,  of  the  human  fetus,  21.  685. 

Lapponian  language,  highly  artificial,  103. 

Lark,  proportion  of  the  sexes  in  the,  281 ;  female,  singing  of  the,  420. 

Larks,  attracted  by  a  mirror,  469. 

Lartet,  E.,  comparison  of  cranial  capacities  of  skulls  of  recent  and 
tertiary  mammals,  62;  on  the  size  of  the  brain  in  mammals,  91;  on 
Dryopithecus,  177;  on  pre  historic  flutes,  650. 

Larus,  seasonal  change  of  plumage  in,  561. 

Larva,  luminous,  of  a  Brazilian  beetle,  314. 

Lamyx,  muscles  of  the,  in  song  birds,  421. 

Lasiocampa  quercus,  attraction  of  males  by  the  female,  284;  sexual 
difference  of  color  in,  358. 

Latham,  R.  G.,  on  the  migrations  of  man,  53. 

Latooka,  perforation  of  the  lower  lip  by  the  women  of,  656. 

Laurillard,  on  the  abnomal  division  of  the  malar  bone  in  man,  44. 

Lawrence,  W.,  on  the  superiority  of  savages  to  Europeans  in 
power  of  sight,  38;  on  the  color  of  negro  infants,  636;  on  the  fond- 
ness of  savages  for  ornaments,  654;  on  beardless  races,  662;  on  the 
beauty  of  the  English  aristocracy,  670. 

Layard,  E.  L.,  on  the  instance  of  rationality  in  a  cobra,  399;  on 
the  pugnacity  of  Gallus  Stanleyi,  412. 

Lay  cock,  Dr.,  on  vital  periodicity,  8;  theroid  nature  of  idiots,  41. 

Leaves,  autumn,  tints,  useless,  296. 

Lecky,  Mr.,  on  the  sense  of  duty,  111;  on  suicide,  132;  on  the 
practice  of  celibacy,  135;  his  view  of  the  crimes  of  savages,  135;  on 
the  gradual  rise  of  morality,  141. 

Leconte,  J.  L,,  on  the  stridulant  organ  in  the  Coprini  and  Dynas- 
tini,  344. 

Lee,  H.,  on  the  numerical  proportion  of  the  sexes  in  the  trout,  282. 

Leg,  calf  of  the,  artifically  modified,  655. 

Legitimate  and  illegitimate  children,  proportion  of  the  sexes  in,  276. 

Legs,  variation  of  the  length  of  the,  in  man,  29;  proportions  of,  in 
soldiers  and  sailors,  36;  front,  atrophied  in  some  male  butterflies, 
314;  peculiarities  of,  in  male  insects,  314. 

Leguay,  on  the  occurrence  of  the  supra-condyloid  foramen  in  the 
humerus  of  man,  24. 

"  Lek  "  of  the  black  cock  and  capercailzie,  460. 

Lemoine,  Albert,  on  the  origin  of  language,  98. 

Lemur  macaco,  sexual  difference  of  color  in,  613. 

Lemurida?,  173;  ears  of  the,  17;  variability  of  the  muscles  in  the, 
46;  position  and  derivation  of  the,  178;  their  origin,  188. 


758  iNDEt. 

Lemurs,  uterus  in  the,  43. 

Lenguas,  disfigurement  of  the  ears  of  the,  656. 

Leopards,  black,  616. 

Lepidoptera,  348;  numerical  proportions  of  the  sexes  in  the,  ^^; 
coloring  of,  349;  ocellated  spots  of,  486. 

Lepidosiren,  180,  187. 

Leptalides,  mimicry  of,  368. 
Leptorhynchus  angustatus,  pugnacity  of  male,  339. 

Leptura  testacea,  difference  of  color  in  the  sexes  of,  333. 

Leroy,  on  the  wariness  of  young  foxes  in  hunting  districts,  90;  on 
the  desertion  of  their  young  by  swaljows,  122. 

Leslie,  D.,  marriage  customs  of  KaflBrs,  683. 

Lesse,  valley  of  the,  24. 

Lesson,  on  the  birds  of  paradise,  248,  457;  on  the  sea-elephant,  603. 

Lessona,  M.,  observations  on  Serranus,  184. 

Lethrus  cephalotes,  pugnacity  of  the  males  of,  337,  340. 

Leuciscus  phoxinus,  282. 

Leuckart,  R.,  on  the  vedcida  prostatica,  26;  on  the  influence  of  the 
age  of  parents  on  the  sex  of  offspring,  277. 

Levator  clavicidm,  muscle,  47. 

Libellula  depressa,  color  of  the  male,  329. 

Libellulidae,  relative  size  of  the  sexes  of,  316;  difference  in  the 
sexes  of,  329. 

Lice  of  domestic  animals  and  man,  193. 

Licentiousness  a  check  upon  population,  52;  prevalence  of,  among 
savages,  134. 

Lichenstein,  on  Cher  a  progne,  476. 

Life,  inheritance  at  corresponding  periods  of,  259,  263. 

Light,  effects  on  complexion,  36;  influence  of,  upon  the  colors  of 
shells,  298. 

Lilford,  Lord,  the  ruff  attracted  by  bright  objects,  469. 

Limosa  lapponica,  544. 

Linaria^  525;  linaria  raontana,  281. 

Lindsay,  Dr.  W.  L.,  diseases  communicated  from  animals  to  man, 
8;  madness  in  animals,  89;  the  dog  considers  his  master  his  God,  108. 

Linnaeus,  views  of,  as  to  the  position  of  man,  170. 

Linnet,  numerical  proportion  of  the  sexes  in  the,  281;  crimson 
forehead  and  breast  of  the,  447;  courtship  of  the,  455. 

Lion,  polygamous,  247;  mane  of  the,  defensive,  594;  roaring  of 
the,  601. 

Lions,  stripes  of  young,  528. 

Lips,  piercing  of  tlie,  by  savages,  657. 

Lithobius,  prehensile  appendages  of  the  female,  310. 

Lithosia,  coloration  in,  356. 

Littorina  littorea,  296. 

Livingstone,  Dr.,  manner  of  sitting  of  gorilla,  172;  on  the  influence 
of  dampness  and  dryness  on  the  color  of  the  skin,  220;  on  the 
liability  of  negroes  to  tropical  fevers  after  residence  in  a  cold  climate, 
220;  on  the  spur- winged  goose,  414;  on  weaver- birds,  427;  on  an 
African  night-jar,  436,  457;  on  the  battle-scars  of  South  African 
male  mammals,  570;  on  the  removal  of  the  upper  incisors  by  the 
Katokas,  656;  on  the  perforation  of  the  upper  lip  by  the  Makalolo, 
657;  on  the  Banyai,  661. 


INDEX,  759 

Livonia,  numerical  proportion  of  male  and  female  births  in,  243, 
275. 

Lizards,  relative  size  of  the  sexes  of,  401 ;  gular  pouches  of,  402. 

Lloyd,  L.,  on  the  polygamy  of  the  capercailzie  and  bustard,  248; 
on  the  numeral  proportion  of  the  sexes  in  the  capercailzie  and  black- 
cock, 280;  on  the  salmon,  378;  on  the  colors  of  the  sea- scorpion.  382; 
on  the  pugnacity  of  male  grouse,  415;  on  the  capercailzie  and 
black-cock,  416,  420;  on  the  call  of  the  capercailzie,  425;  on  assem- 
blages of  grouse  and  snipes,  460;  on  the  pairing  of  a  shield-drake 
with  a  common  duck,  471 ;  on  the  battles  of  seals,  571 ;  on  the  elk, 
579. 

Lobivandlus,  wing-spurs  in,  414. 

Local  influences,  effect  of,  upon  stature,  34. 

Lock  wood,  Mr.,  on  the  development  of  Hippocampus,  185. 

Lockwood,  Rev.  S.,  musical  mouse,  648. 

Locust,  bright- colored,  rejected  by  lizards  and  birds,  328. 

Locust,  migratory,  321;  selection  by  female,  321. 

Locustidae,  stridulation  of  the  320,  322;  descent  of  the,  323. 

Locusts,  proportion  of  sexes  in,  287;  stridulation  of,  321. 

Longicorn  beetles, IdifEerence  of  the  sexes  of,  in  color,  333;  stridula- 
tion of,  343. 

Lonsdale,  Mr.,  on  an  example  of  personal  attachment  in  Helix 
pomatia,  296. 

Lophobranchii  marsupial  receptacles  of  the  male,  392 

Lophophorus,  habits  of,  477. 

Lophorina  atra^  sexual  difference  in  coloration  of,  559. 

Lophornis  ornatus,  439. 

Lord,  J.  K.,  on  Salmo  lycaodon,  377. 

liory,  King,  521;  immature  plumage  of  the,  532. 

Lory,  king,  constancy  of,  466. 

Love-antics  and  dances  of  birds,  431. 

Lowne,  B.  T.,  on  Musca  v&mitoi'ia,  61,  318. 

Loxia,  characters  of  young  of,  529. 

Lubbock,  Sir  J.,  on  the  antiquity  of  man,  2;  on  the  origin  of  man, 
3;  on  the  mental  capacity  of  savages,  73;  on  the  origin  of  imple- 
ments, 93;  on  the  simplification  of  languages,  104;  on  the  absence  of 
the  idea  of  God  among  certain  races  of  men,  106;  on  the  origin  of  the 
belief  in  spiritual  agencies,  107;  on  superstitions,  108;  on  the  sense 
of  duty,  111;  on  the  practice  of  burying  the  old  and  sick  among  the 
Fijians,  116;  on  the  immorality  of  savages,  135 ;  on  Mr.  Wallace's 
claim  to  the  origination  of  the  idea  of  natural  selection,  55;  on  the 
former  barbarism  of  civilized  nations,  162;  on  improvements  in  the 
arts  among  savages,  164;  on  resemblances  of  the  mental  characters 
in  different  races  of  men,  203;  on  the  arts  practiced  by  savages,  204; 
on  the  power  of  counting  in  primeval  man,  204;  on  the  prehensile 
organs  of  the  male  LaMdocera  Darmnii,  301;  on  C  fdoeon,  311;  on 
Smynthuriis  luteus,  317;  finding  of  new  mates  by  jays,  463;  on  strife 
for  women  among  the  North  American  Indians,  640;  on  music,  650; 
on  the  ornamental  practices  of  savages,  654;  on  the  estimation  of  the 
beard  among  the  Anglo-Saxons,  663;  on  artificial  defonnation  of  the 
skull,  565;  on  "communal  marriages,"  671;  on  oxogamy,  673,  676; 
on  the  Veddahs,  675;  on  polyandry,  677. 

Lucanidae,  variability  of  the  mandibles  in  the  male,  339. 


%0  INDEX. 

Liicanus,  large  size  of  males  of,  316;  lucanus  cervus,  numerical 
proportion  of  sexes  of,  286  ;  weapons  of  the  male,  839;  lucanus 
elaphus,  use  of  mandibles  of,  340;  large  jaws  of  male,  312. 

Lucas  Prosper,  on  pigeons,  475;  on  sexual  preference  in  horses  and 
bulls,  598. 

Luminosity  in  insects,  314. 

Lunar  periods,  8,  187. 

Lund,  Dr.,  on  skulls  found  in  Brazilian  caves,  192. 

Lungs,  enlargement  of,  in  tlie  Quicliua  and  Aymara  Indians,  38; 
a  modified  swim-bladder,  183 ;  different  capacity  of,  in  races  of 
man,  191. 

Luscbka,  Prof, ,  on  tbe  termination  of  the  coccyx,  25. 

Luxury,  expectation  of  life  uninfluenced  by,  154. 

Lycceiia,  sexual  differences  of  color  in  species  of,  351 . 

Lycsenae,  colors  of,  354. 

Lyell,  Sir  C,  on  the  antiquity  of  man,  2;  on  the  origin  of  man,  3; 
on  the  parallelism  of  the  development  of  species  and  languages,  102; 
on  the  extinction  of  languages  102;  on  the  Inquisition,  160;  on  the 
fossil  remains  of  vertebrata,  178;  on  the  fertility  of  mulattoes,  194. 

Lynx,  Canadian,  throat-ruff  of  the,  594. 

Lyre-bird,  assemblies  of,  461. 

Macacm,  ears  of,  17;  convoluted  body  in  the  extremity  of  the  tail 
of,  26;  variability  of  the  tail  in  species  of,  65;  whiskers  of  species  of, 
607;  macacus  brunneus,  66;  macacus  cynomolgus,  superciliary  ridge 
of,  636;  beard  and  whiskers  of,  becoming  white  with  age,  637; 
macacus  ecaudatus,  67;  macacus  lasiotus,  facial  spots  of,  629;  maca- 
cus nemenstrinus,  710;  macacus  radiatus,  171;  macacus  rhesus,  sexual 
difference  in  the  color  of,  616,  629. 

Macalister,  Prof.,  on  variations  of  the  palmuHs  accessorius  muscle, 
30;  on  muscular  abnormalities  in  man,  47,  48;  on  the  greater  varia- 
bility of  the  muscles  in  men  than  in  women,  253. 

Macaws,  Mr.  Buxton's  observations  on,  115,  425. 

McCann,  J.,  on  mental  individuality,  95. 

McClelland  J.,  on  the  Indian  Cyprinidae,  389. 

Macculloch,  Col.,  on  an  Indian  village  without  any  female 
children,  676. 

Macculloch,  Dr. ,  on  tertian  ague  in  a  dog,  8. 

Macgillivray,  W.,  on  the  vocal  organs  of  birds,  101;  on  the 
Egyptian  goose,  414;  on  the  habits  of  woodpeckers,  427;  on  the 
habits  of  the  snipe,  428;  on  the  whitethroat,  432;  on  the  moulting 
of  the  snipes,  444;  on  the  moulting  of  the  Anatidae,  446;  on  the 
finding  of  new  mates  by  magpies,  453;  on  the  pairing  of  a  blackbird 
and  thrush,  470;  on  pied  ravens,  482  ;  on  the  guillemots,  482;  on 
the  colors  of  the  tits,  521;  on  the  immature  plumage  of  birds,  530, 
et  seq. 

Machetes,  sexes  and  young  of,  553,  et  seq.;  machetes pugnax,  sup- 
posed to  be  polygamous,  248;  numerical  proportion  of  the  sexes  in, 
280;  pugnacity  of  the  male,  409;  double  moult  in,  443. 

Mcintosh,  Dr.,  colors  of  the  Nemertians,  299. 

McKennan,  marriage  customs  of  Koraks,  684. 

Mackintosh,  on  the  moral  sense,  110. 

MacLachlan,  R.,  on  Apatania  muliebHs  and  B or eu s  hy emails,  287; 
on   the   anal   appendages   of   male   insects,  311;  on   the   pairing  of 


INDEX.  761 

dragon  flies,  316;  on  dragon  flies,  329;  on  dimorphism  in  Agrion, 
329;  on  the  want  of  pugnacity  in  male  dragon  flies,  330;  color  of 
ghost-moth  in  the  Shetland  Islands,  359. 

M'Lennan,  Mr.,  on  infanticide,  52,  675;  on  the  origin  of  the  belief 
in  spiritual  agencies,  106;  on  the  prevalence  of  licentiousness  among 
savages,  134,  671;  on  the  primitive  barbarism  of  civilized  nations, 
162;  on  traces  of  the  custom  of  the  forcible  capture  of  wives,  163, 
676;  on  polyandry,  677. 

Macnamara,  Mr.,  susceptibility  of  Andaman  Islanders  and  Nepalese 
to  change,  214. 

McNeill,  Mr.,  on  the  use  of  the  antlers  of  deer,  582;  on  the  Scotch 
deerhound,  589;  on  the  long  hail's  on  the  throat  of  the  stag,  595;  on 
the  bellowing  of  stags,  600. 

Macropus,  courtship  of,  387. 

Macrorhinus  prohoscideuSy  structure  of  the  nose  of,  603. 

Magpie,  power  of  speech  of,  101;  vocal  organs  of  the,  421;  nuptial 
assemblies  of,  461;  new  mates  found  by,  462;  stealing  bright  objects, 
469;  young  of  the,  548;  coloration  of  the,  562. 

Maillard,  M.,  on  the  proportion  of  the  sexes  in  a  species  of  PapUio 
from  Bourbon,  283; 

Maine,  Sir  Henry,  on  the  absorption  of  one  tribe  by  another,  145; 
a  desire  for  improvement  not  general,  150. 

Major,  Dr.  C.  Forsyth,  on  fossil  Italian  apes,  177;  skull  of  Bos 
etruscus,  576;  tusks  of  miocene  pigs,  593. 

Makalolo,  perforation  of  the  upper  lip  by  the,  657. 

Malar  bone,  abnormal  division  of,  in  man,  44. 

Malay,  Archipelago,  marriage-customs  of  the  savages  of  the,  683. 

Malays,  line  of  separation  between  the  Papuans  and  the,  192;  gen- 
eral beardlessness  of  the,  639;  staining  of  the  teeth  among,  655; 
aversion  of  some,  to  hairs  on  the  face,  662;  and  Papuans,  contrasted 
characters  of,  191. 

Male  animals,  struggles  of,  for  the  possession  of  the  females,  239, 
241;  eagerness  of,  in  courtship,  250,  251;  generally  more  modified 
than  female,  250,  252;  differ  in  the  same  way  from  females  and 
young,  263;  characters,  developed  in  females,  257;  transfer  of,  to 
female  birds,  537;  sedentary,  of  a  hymenopterous  parasite,  251, 

Malefactors,  155. 

Males,  presence  of  rudimentary  female  organs  in,  184;  and  females, 
comparative  numbers  of,  241,  244  ;  comparative  mortality  of,  while 
young,  244. 

Malherbe,  on  the  woodpeckers,  521. 

Mallotus  Peronii,dl6;  viMoms,  375. 

Malthus,  T.,  on  the  rate  of  increase  of  population,  50,  51,  52. 

Maluridse,  nidification  of  the,  517. 

Malwnis,  young  of,  553. 

Mammae,  235;  rudimentary,  in  male  mammals,  12,  26,  183,  184, 
185;  supernumerary,  in  women,  41;  of  male  human  subject,  42. 

Mammalia,  Prof.  Owen's  classification  of,  168;  genealogy  of  the, 
180. 

Mammals,  recent  and  tertiary,  comparison  of  cranial  capacity  of, 
62;  nipples  of,  184;  pursuit  of  female,  by  the  males.  250;  secondary 
sexual  characters  of,  570;  wea])<)ns  of,  571;  relative  size  of  the  sexes 
of,  588;  parallelism  of,  with  birds  in  secondary  sexual  characters, 
618;  voices  of,  used  especially  during  the  breeding  season,  647. 


762  INDEX. 

Man,  variability  of,  29;  erroneously  regarded  as  more  domesticatett 
than  other  animals,  31;  migrations  of,  58;  wide  distribution  of,  53; 
causes  of  the  nakedness  of,  63;  supposed  physical  inferiority  of,  72; 
a  member  of  the  Catarrhine  group,  176;  early  progenitors  of,  182; 
transition  from  ape  indefinite,  205;  numerical  proportions  of  thfe 
sexes  in,  243;  difference  between  the  sexes,  252;  proportion  of  sexeS 
among  the  illegitimate,  276 ;  different  complexion  of  male  and 
female  negroes,  634  ;  secondary  sexual  characters  of,  634;  primeval 
condition  of,  678.    , 

Mandans,  correlation  of  color  and  texture  of  hair  in  the,  225. 

Mandible,  left,  enlarged  in  the  male  of  Taphruderes  distortus,  313. 

Mandibles,  use  of  the,  in  Ammophila,  312;  large,  of  Corydalis 
cornutus,  312;  large,  of  male  Lncanus  elaphus,  312. 

Mandrill,  number  of  caudal  vertebrje  in  the,  65;  colors  of  the  male, 
614,  617,  629. 

Mantegazza,  Prof.,  on  last  molar  teeth  of  man,  22;  bright  colors 
in  male  animale,  254;  on  the  ornaments  of  savages,  654  et  seq.;  on 
the  beardlessness  of  the  New  Zealanders,  663;  on  the  exaggeration 
of  natural  characters  by  man,  664. 

Mantell,  W.,  on  the  engrossment  of  pretty  girls  by  the  New  Zea- 
land chiefs,  680. 

Mantis,  pugnacity  of  species  of,  710. 

Maories,  mortality  of,  210;  infanticide  and  proportion  of  sexes, 
3^;  distaste  for  hairiness  among  men,  663; 

Marcus  Aurelius,  on  the  origin  of  the  moral  sense,  111;  on  the 
influence  of  habitual  thoughts,  139. 

Mareca  penelope,  471. 

Marks,  retained  throughout  groups  of  birds,  485. 

Marriage,  restraints  upon,  among  savages,  50;  influence  of,  upon 
morals,  134;  influence  of,  on  mortality,  157;  development  of,  673. 

Marriages,  early,  156  et  seq.;  commual,  670,  672. 

Marshall,  Dr.  W.,  protuberances  on  birds'  heads,  266,  435;  on  the 
moulting  of  birds,  445;  advantage  to  older  birds  of  paradise,  552; 
Marshall,  Col.,  interbreeding  among  Todas,  215  ;  infanticide  and 
proportion  of  sexes  with  Todas,  288 ;  choice  of  husband  among 
Todas,  677;  Marshall,  Mr.,  on  the  brain  of  a  Bush  woman,  191. 

Marsupials,  179;  development  of  the  nictitating  membrane  in,  19; 
uterus  of,  43  ;  possession  of  nipples  by,  185  ;  their  origin  from 
Monotremata,  188;  abdominal  sacs  of,  235;  relative  size  of  the  sexes 
of,  588;  colors  of,  609. 

Marsupium,  rudimentary,  in  male  marsupials,  183. 

Martin,  W.  C.  L.,  on  alarm  manifested  by  an  orang  at  the  sight  of 
a  turtle,  81;  on  the  hair  in  Ilylohates,  172;  on  a  female  American 
deer,  586;  on  the  voice  of  IJyluhntes  agilis,  602;  on  Semnopithecui 
nemceus,  630;  on  the  beards  of  the  inhabitants  of  St.  Kilda,  638. 

Martins  deserting  their  young,  122. 

Martin,  C,  on  death  caused  by  inflammation  of  the  vermiform 
appendages,  23. 

Mastoid  processes  in  man  and  apes,  59. 

Maudsley,  Dr.,  on  the  influence  of  the  sense  of  smell  in  man,  20; 
on  idiots  smelling  their  food,  41;  on  Laura  Bridgman,  99;  on  the 
development  of  the  vocal  organs,  101;  moral  sense  failing  in 
incipient  madness,  140;  change  of  mental  faculties  at  puberty  in  man, 
644. 


INDEX.  %t 

Mayers,  W.  F. ,  on  the  domestication  of  the  goldfish  in  China,  389. 
Mayhew,  E.,  on  the  affection  between  individuals  of  different  sexes 
in  the  dog,  596. 

Maynard,  C.  J.,  on  the  sexes  of  Ghrysemys picta,  397. 

Meckel,  on  correlated  variation  of  the  muscles  of  the  arm  and 
leg,  49. 

Medicines,  effect  produced  by,  the  same  in  man  and  in  monkeys,  7. 

MeduscE,  bright  colors  of  some,  295. 

Megalithic  structures,  prevalence  of,  204. 

Megapicus  validiis,  sexual  difference  of  color  in,  521. 

Megasoma,  large  size  of  males  of,  316. 

Meigs,  Dr.  A.,  on  variation  in  the  skulls  of  the  natives  of 
America,  29. 

Meinecke,  on  the  numerical  proportion  of  the  sexes  in  butter- 
flies, 283. 

Melanesians,  decrease  of,  211. 

Meldola,  Mr.,  colors  and  marriage  flight  of  Golias  and  Pieris,  362. 

Meliphagidae,  Australian  nidification  of,  517. 

Melita,  secondary  sexual  characters  of,  303. 

Meloe,  difference  of  color  in  the  sexes  of  a  species  of,  333. 

Memnon,  young,  192. 

Memory,  manifestations  of,  in  animals,  83. 

Mental  characters,  difference  of,  in  different  races  of  men,  191; 
faculties,  diversity  of,  in  the  same  race  of  men,  30;  inheritance  of, 
31;  variation  of,  in  the  same  species,  31,  74;  similarity  of  the,  in  dif- 
ferent races  of  man,  203;  of  birds,  466;  powers,  difference  of,  in  the 
two  sexes  in  man,  642. 

Menura  Alberti,  461;  song  of,  421;  menura  superba,  461;  long 
tails  of  both  sexes  of,  513. 

Merganser,  trachea  of  the  male,  425;  merganser  serrator,  male 
plumage  of,  446. 

Mergus  cucidlatus,  speculum  of,  267;  mergus  merganser,  young 
of,  532. 

Metallura,  splendid  tail-feathers  of,  503. 

Methoca  ichneumonides,  large  male  of,  316. 

Meves,  M.,  on  the  drumming  of  the  snipe,  428. 

Mexicans,  civilization  of  the,  not  foreign,  164. 

Meyer,  on  a  convoluted  body  at  the  extremity  of  the  tail  in  a 
Macacus  and  a  cat,  25. 

Meyer,  Dr.  A.,  on  the  copulation  of  Phryganidae  of  distinct 
species,  312. 

Meyer,  Prof.  L.,  on  development  of  helix  of  ear,  16  et  seq.;  men's 
ears  more  variable  than  women's,  253;  antennae  serving  as  ears,  318. 

Migrations  of  man,  effects  of,  53. 

Migratory  instinct  of  birds,  119;  vanquishing  the  maternal,  122, 128. 

Mill,  J.  S.,  on  the  origin  of  the  moral  sense.  111;  on  the  "greatest 
happiness  principle,"  135;  on  the  difference  of  the  mental  powers  in 
the  sexes  of  man,  644. 

Millipedes,  310. 

Milne-Edwards  H.,  on  the  use  of  enlarged  chelae  of  the  male 
Oelasimus,  303. 

Milvago  leucurus,  sexes  and  young  of,  546. 

Mimicry,  366. 


764  INDEX. 

Mimus  polyglottus,  467. 

Mind,  difference  of,  in  man  and  the  highest  animals,  143;  similarity 
of  the,  in  different  races,  203. 

Minnow,  proportion  of  the  sexes  in  the,  282. 

Mirror,  behavior  of  monkeys  before,  709. 

Mirrors,  larks  attracted  by,  469. 

Mitchell,  Dr.,  interbreeding  in  the  Hebrides,  215. 

Mitford,  selection  of  children  in  Sparta,  32. 

Mivart,  St.  George,  on  the  reduction  of  organs,  13;  on  the  ears  of 
the  lemuroidea,  17;  on  variability  of  the  muscles  in  leuiuroidea,  46, 
54;  on  the  caudal  vertebrae  of  monkeys,  65;  on  the  classification  of 
the  primates,  174;  on  the  orang  and  on  man,  175;  on  differences  in 
the  lemuroidea,  176;  on  the  crest  of  the  male  newt,  395. 

Mcibius,  Prof.,  on  reasoning  powers  in  a  pike,  85. 

Mocking-thrush,  partial  migration  of,  467;  young  of  the,  554. 

Modifications,  unserviceable,  69. 

Moggridge,  J.  T.,  on  habits  of  spiders,  77;  on  habits  of  ants,  168. 

Moles,  numerical  proportion  of  the  sexes  in,  279;  battles  of 
male,  570. 

Mollieneda  petenensis,  sexual  difference  in,  382. 

Mollusca,  beautiful  colors  and  shapes  of,  298;  absence  of  secondary 
sexual  characters  in  the,  296. 

MoUuscoida,  181,  296. 

Monacanthus  scopas  and  M.  Peronii,  376. 

Monboddo,  Lord,  on  music,  653. 

Mongolians,  perfection  of  the  senses  in,  38. 

Monkey,  protecting  his  keeper  from  a  baboon,  117,  125;  bonnet, 
171;  rhesus,  sexual  difference  in  color  of  the,  615,  629;  mustache, 
colors  of  the,  614. 

Monkeys,  liability  of,  to  the  same  diseases  as  man,  7;  male,  recog- 
nition of  women  by,  9;  diversity  of  the  mental  faculties  in,  31; 
breaking  hard  fruits  with  stones,  56;  hands  of  the,  56,  57;  basal 
caudal  vertebrae  of,  imbedded  in  the  body,  66;  revenge  taken  by,  78; 
maternal  affection  in,  79;  variability  of  the  faculty  of  attention  in, 
83;  American,  manifestation  of  reason  in,  87 ;  using  stones  and 
sticks,  91;  imitative  faculties  of,  98;  signal-«ries  of,  98;  mutual 
kindnesses  of,  115;  sentinels  posted  by,  114;  human  characters  of, 
171;  American,  direction  of  the  hair  on  the  arms  of  some,  172;  grada- 
tion of  species  of,  199;  beards  of,  607;  ornamental  characters  of, 
626;  analogy  of  sexual  differences  of,  with  those  of  man,  636; 
different  degrees  of  difference  in  the  sexes  of,  640;  expression  of 
emotions  by,  652;  generally  monogamous  habits  of,  674;  polygamous 
habits  of  some,  674;  naked  surfaces  of,  686:  courtship  of,  709. 

Monogamy,  not  primitive,  164. 

Monogenists,  200. 

Mononychus  pseudacori,  stridulation  of,  345. 

Monotremata,  179;  development  of  the  nictitating  membrane 
in,  19;  lactiferous  glands  of,  184;  connecting  mammals  with  reptiles, 
188. 

Monstrocities,  analogous  in  man  and  lower  animals,  33;  caused  by 
arrest  of  development,  40;  correlation  of,  49;  transmission  of,  197. 

Montagu,  U.,  on  the  habits  of  the  black  and  red  grouse,  248;  on 
the  pugnacity  of  the  ruff,  409,  410;  on  the  singing  of  birds,  418;  on 
the  double  moult  of  the  male  pintail,  446. 


INDEX.  765 

Monteiro,  Mr.,  on  the  Bucorax  abyssinicus,  435. 

Montes  de  Oca,  M.,  on  the  pugnacity  of  male  humming-birds,  408. 

Monticola  cyanea,  519. 

Monuments,  as  traces  of  extinct  tribes,  206. 

Moose,  battles  of,  571;  horns  of  the,  an  incumberance,  587. 

Moral  and  instinctive  impulses,  alliance  of,  125;  faculties,  their  in- 
fluence on  natural  selection  in  man,  144;  rules,  distinction  between 
the  higher  and  lower,  138;  sense,  so-called,  derived  from  the  social 
instincts,  136;  origin  of  the,  140;  tendencies,  inheritance  of,  140. 

Morality,  supposed  to  be  founded  in  selfishness,  135;  test  of,  the 
general  warfare  of  the  community,  137;  gradual  rise  of,  141;  in- 
fluence of  a  high  standard  of,  149. 

Morgan,  L.  H.,  on  the  beaver,  75;  on  the  reasoning  powers  of  the 
beaver,  84;  on  the  forcible  capture  of  wives,  163;  on  the  castoreum 
of  the  beaver,  604;  marriage  unknown  in  primeval  times,  671;  on 
polyandry,  677. 

Morley,  J.,  on  the  appreciation  of  praise  and  fear  of  blame,  163. 

Morris,  F.  0.,  on  hawks  feeding  an  orphan  nestling,  465. 

Morse,  Dr.,  colors  of  mollusca,  298. 

Morselli,  E.,  division  of  the  malar  bone,  44. 

Mortality,  comparative,  of  female  and  male,  244,  275. 

Morton,  on  the  number  of  species  of  man,  199. 

Moschkau,  Dr.  A.,  on  a  speaking  starling,  96. 

Moschus  moschiferus,  odoriferous  organs  of,  605. 

MotacillcB,  Indian,  young  of,  534. 

Moth,  odoriferous,  349. 

Moths,  355;  absence  of  mouth  in  some  males,  235;  apterous  female, 
235;  male,  prehensile  use  of  the  tarsi  by,  237;  male,  attracted  by 
females,  284;  sound  produced  by,  349;  coloration  of,  357;  sexual  dif- 
ferences of  color  in,  358. 

Motmot,  inheritance  of  mutilation  of  tail  feathers,  67,  689;  racket- 
shaped  feathers  in  the  tail  of  a,  436. 

Moult,  double,  526;  double  annual,  in  birds,  442. 

Moulting  of  birds,  551. 

Moults,  partial,  444. 

Mouse,  song  of,  648. 

Mustache-monkey,  colors  of  the,  614,  630. 

Mustaches,  in  monkeys,  171. 

Mud-turtle,  long  claws  of  the  male,  397. 

Mulattoes,  persistent  fertility  of,  194;  immunity  of,  from  yellow 
fever,  220. 

Mule,  sterility  and  strong  vitality  of  the,  195. 

Mules,  rational,  88. 

Muller,  Ferd.,  on  the  Mexicans  and  Peruvians,  164;  Fritz;  on  asto- 
matous  males  of  Taitais,  235;  on  the  disappearance  of  spots  and 
stripes  in  adult  mammals,  625;  on  the  proportions  of  the  sexes  in 
some  Crustacea,  287  ;  on  secondary  sexual  characters  in  various 
Crustaceans,  300,  et  seq.;  musical  contest  between  male  Cicidce,  320; 
mode  of  holding  wings  in  Castina,  357;  on  birds  showing  a  preference 
for  certain  colors,  359;  on  the  sexual  maturity  of  young  amphipod 
Crustacea,  552. 

Miiller,  Hermann,  emergence  of  bees,  from  pupa,  242;  pollen- 
gathering  of  bees,  258;  proportion  of  sexes  in  bees,  286;  courting  of 


766  INDEX. 

Rristalis,  318;  color  and  sexual  selection  with  bees,  331;  J.,  on  the 
nictitating  membrane  and  semilunar  fold,  19;  Max,  on  tlie  origin  of 
language,  98;  language  imjilies  power  of  general  conception,  100; 
struggle  for  life  among  the  words,  etc.,  of  languages,  102;  S.,  on  the 
banteng,  613;  on  the  colors  of  Semnopithecus  chrysomelas,  613. 

Muntjac-deer,  weapons  of  the,  586. 

Murie,  J.,  on  the  reduction  of  organs,  13;  on  the  ears  of  the  Lemu- 
roidea,  17;  on  variability  of  the  muscles  in  the  Lemuroidea,  46,  54; 
basal  caudal  vertebrae  of  Mncaeus  hrunueus  imbedded  in  the  body, 
67;  on  the  manner  of  sitting  in  short-tailed  apes,  67;  on  differences 
in  the  Lemuroidea,  176  ;  on  the  throat-pouch  of  the  male  bustard, 
423;  on  the  mane  of  Otaria  jvhata,  594;  on  the  sub-orbital  pits  of 
Ruminants,  605;  on  the  colors  of  the  sexes  in  Otaria  nigrescens,  610. 

Murray,  A.,  on  the  Pediculi  of  different  races  of  men,  193;  T.  A., 
on  the  fertility  of  Australian  women  with  white  men,  194. 

Mus  coninga,  91;  mi?iutu8,  sexual  difference  in  the  color  of,  610. 

Miisca  vomitoria,  61. 

Muscicapa  grisola,  518;  Itictuosa^  518;  ruticilla,  breeding  in  imma- 
ture plumage,  551. 

Muscle,  isciiio-pubic,  46. 

Muscles,  rudimentary,  occurrence  of,  in  man,  13  ;  variability  of 
the  30;  effects  of  use  and  disuse  upon,  36;  animal-like  abnormalities 
of,  in  man,  46;  correlated  variation  of,in  the  arm  and  leg,  49;  variability 
of,  in  the  hands  and  feet,  54;  of  the  jaws,  influence  of,  on  the  phy- 
siognomy of  the  apes,  50;  habitual  spasms  of,  causing  modifications  of 
the  facial  bones,  62;  of  the  early  progenitors  of  man,  182;  greater 
variability  of  the,  in  men  than  in  women,  252. 

Muculus  sternalis.  Prof.  Turner,  on  the,  14. 

Music,  203;  of  bird,  417,  discordant,  love  of  savages  for,  431; 
reason  of  power  of  perception  of  notes  in  animals,  648;  power  of  dis- 
tinguishing notes  649;  its  connection  with  primeval  speech,  652;  dif- 
ferent appreciation  of,  by  different  peoples, 651;  origin  of,  650,  653; 
effects  of,  651 . 

Musical  cadences,  perception  of,  by  animals,  649;  powers  of  man, 
645,  et  seq. 

Musk-deer,  canine  teeth  of  male,  572,  586 ;  male,  odoriferous 
organs  of  the,  604;  winter  change  of  the,  619. 

Musk-duck,  Australian,  407;  large  size  of  male,  411;  of  Guiana, 
pugnacity  of  the  male,  411. 

Musk-ox,  horns  of,  576. 

Musk-rat,  protective  resemblance  of  the,  to  a  clod  of  earth,  619. 

Musoj)1inga>,  colors  and  nidification  of  the,  518;  both  sexes  of, 
equally  brilliant,  523, 

Mussels  opened  by  monkeys,  56. 

Mustela,  winter  change  of  two  species  of,  619. 

Musters,  Capt.,  on  Rhea  Darwinii,  545;  marriages  among  Pata- 
gonians,  683. 

Mutilations,  healing  of,  8;  inheritance  of,  67. 

MutUla  europcea,  stridulation  of,  332. 

Mutillidae,  absence  of  ocelli  in  female,  311. 

Mycetes  caraya,  polygamous,  245;  vocal  organs  of,  602;  beard  of, 
607;  sexual  differences  of  color  in,  613;  voice  of,  647;  mycetes  seni- 
culus,  sexual  differences  of  color  in,  613, 


INDEX.  767 

Myriapoda,  310. 

Nageli,  on  the  influence  of  natural  selection  on  plants,  68;  on  the 
gradation  of  species  of  plants,  199. 

Nails,  colored  yellow  or  purple  in  part  of  Africa,  655. 

Narwhal,  tusks  of  the,  572,  578. 

Nasal  cavities,  large  size  of,  in  American  aborigines,  38. 

Nascent  organs,  12. 

Nathusius,  H.  von,  on  the  improved  breeds  of  pigs,  201  ;  male 
domesticated  animals  more  variable  than  females,  252  ;  horns  of 
castrated  sheep,  577;  on  the  breeding  of  domestic  animals,  680. 

Natural  selection,  its  effects  on  the  early  progenitors  of  man,  53; 
influence  of,  on  man,  67,  70  ;  limitation  of  the  principle,  68;  in- 
fluence of,  on  social  animals,  70;  Mr.  Wallace  on  the  limitation  of, 
by  the  influence  of  the  mental  faculties  in  man,  144;  influence  of, 
in  the  progress  of  the  United  States,  161 ;  in  relation  to  sex,  292. 

Natural  and  sexual  selection  contrasted,  256. 

Naulette,  jaw  from,  large  size  of  the  canines  in,  46. 

Neanderthal  skull,  capacity  of  the,  61. 

Neck,  proportion  of,  in  soldiers  and  sailors,  36. 

Necrophoru8y  stridulation  of,  342,  345. 

Nectarinia,  young  of,  533. 

NectaHnim,  moulting  of  the,  444;  nidification  of,  517. 

Negro,  resemblance  of  a,  to  Europeans  in  mental  characters,  203. 

Negro- women,  their  kindness  to  Mungo  Park,  133. 

Negroes,  Caucasian  features  in,  190;  character  of,  191;  lice  of,  193; 
fertility  of,  when  crossed  with  other  races,  194;  blackness  of,  194, 
197,  variability  of,  198,  199;  immunity  of,  from  yellow  fever,  220; 
difference  of,  from  Americans,  224;  disfigurements  of  the,  617;  color 
of  new-born  children  of,  635;  comparative  beardlessness  of,  639; 
readily  become  musicians,  650;  appreciation  of  beauty  of  their  women 
by,  659,  661;  idea  of  beauty  among,  664;  compression  of  the  nose  by 
some,  665. 

Nemertians,  colors  of,  299. 

Neolithic  period,  164. 

NeomorpJia,  sexual  difference  of  the  beak  in,  408. 

Nephila,  size  of  male,  309. 

Nests,  made  by  fishes,  391;  decoration  of,  by  humming-birds,  469. 

Neumeister,  on  a  change  of  color  in  pigeons  after  several  moult- 
ings,  269. 

Neuration,  difference  of,  in  the  two  sexes  of  some  butterflies  and 
hymenoptera,  314. 

Neuroptera,  287,  327. 

Neurothemis,  dimorphism  in,  329. 

New  Zealand,  expectation  by  the  natives  of,  of  their  extinction, 
218;  practice  of  tattooing  in,  657;  aversion  of  natives  of,  to  hairs  on 
the  face,  662;  pretty  girls  engrossed  by  the  chiefs  in,  680. 

Newton,  A.,  on  the  throat-pouch  of  the  male  bustard,  423;  on  the 
difference  between  the  females  of  two  species  of  Oxynotus,  536;  on 
the  habits  of  the  Phalarope,  dotterel  and  godwit,  544. 

Newts,  394. 

Nicholson,  Dr.,  on  the  non-immunity  of  dark  Europeans  from 
yellow  fever,  222. 

Nictitating^  membrane,  19,  182. 


768  INDEX. 

Nidification,  of  fishes,  391;  relation  of,  to  color,  515,  519;  of 
British  birds,  517. 

Night-heron,  cries  of  the,  417. 

Nightingale,  arrival  of  the  male  before  the  female,  240;  object  of 
the  song  of  the,  418. 

Nightingales,  new  mates  found  by,  463. 

Nightjar,  selection  of  a  mate  by  the  female,  473;  Australian,  sexes 
of,  546;  coloration  of  the  559. 

Nightjars,  noise  made  by  some  male,  with  their  wings,  426;  elon- 
gated feathers  in,  436,  457. 

Nilghau,  sexual  differences  of  color  in  the,  611. 

Nillson,  Prof.,  on  the  resemblance  of  stone  arrow-heads  from 
various  places,  203;  on  the  development  of  the  horns  in  the  rein- 
deer, 265. 

Nipples,  absence  of,  in  Monotremata,  184. 

Nitsche,  Dr.,  ear  of  fetal  orang,  18. 

Nitzsch,  C.  L.,  on  the  down  of  birds,  442. 

Noctuae,  brightly  colored  beneath,  357. 

Noctuidae,  coloration  of,  355. 

Nomadic  habits,  unfavorable  to  human  progress,  150. 

Nordmann,  A.,  on  Tetrao  urogalloides,  460. 

Norfolk  Island,  half-breeds  on,  217. 

Norway,  numerical  proportion  of  male  and  female  births  in,  275. 

Nose,  resemblance  of,  in  man  and  the  apes,  174;  piercing  and 
ornamentation  of  the,  656;  very  fiat,  not  admired  in  negroes,  664; 
flattening  of  the,  665. 

Nott  and  Gliddon,  on  the  features  of  Ramesis  II,  192;  on  the 
features  of  Amunoph  III,  192;  on  skulls  from  Brazilian  caves,  192; 
on  the  immunity  of  negroes  and  mulattoes  from  yellow  fever, 
220;  on  the  deformation  of  the  skull  among  American  tribes,  665. 

Nudibranch  Mollusca,  bright  colors  of,  296. 

Numerals,  Roman,  163. 

Nunemaya,  natives  of,  bearded,  639. 

Nuthatch,  of  Japan,  intelligence  of,  466;  Indian,  555. 

Obedience,  value  of,  147. 

Observation,  powers  of,  possessed  by  birds,  467. 

Occupations,  sometimes  a  cause  of  diminished  stature,  34;  effect 
of,  upon  the  proportions  of  the  body,  34. 

Ocelli,  absence  of,  in  female  Mutillidae,  311;  of  birds,  formation 
and  variability  of  the,  486. 

Ocelot,  sexual  differences  in  the  coloring  of  the,  610. 

OcypJiaps  lophote8,4:56. 

Odonata,  287. 

Odonestis  potatoria,  sexual  difference  of  color  in,  358. 

Odor,  correlation  of,  with  color  of  skin,  225;  of  moths,  349; 
emitted  by  snakes  in  the  breeding-season,  399;  of  mammals,  603. 

(Ecanthus  nivalis,  difference  of  color  in  the  sexes  of,  328;  cecanthus 
pellucid  us,  328. 

Ogle,  Dr.  W.,  relation  between  color  and  power  of  smell,  19. 

Oidemia,  559. 

Olivier,  on  sounds  produced  by  Pimelia  striata,  347. 

Omaloplia  hrunnea,  stridulation  of,  344. 

Onitis  furcifer,  processes  of  anterior  femora  of  the  male,  and  on 
the  head  and  thorax  of  the  female,  337,  338, 


INDEX,  769 

Ojithophagtis,  336;  onthopJiagus  rangifer,  sexual  differences  of,  335; 
variation  in  the  horns  of  the  male,  336. 
Ophidia,  sexual  differences  of,  398. 

Ophidium,  394. 

Opossum,  wide  range  of,  in  America,  193. 

Optic  nerve,  atrophy  of  the,  caused  by  destruction  of  the  eye,  36. 

Orang  outang,  640;  Bischoff  on  the  agreement  of  the  brain  of  the, 
with  that  of  man,  6;  adult  age  of  the,  9;  ears  of  the,  15;  vermiform 
appendage  of,  23;  hands  of  the,  56;  absence  of  mastoid  processes  in 
the,  59;  platforms  built  by  the,  75;  alarmed  at  the  sight  of  a  turtle, 
81;  using  a  stick  as  a  lever,  91;  using  missiles,  92;  using  the  leaves 
of  the  Paiidanns  as  a  night  covering,  93;  direction  of  the  hair  on 
the  arms  of  the,  172;  its  aberrant  characters,  175;  supposed  evolu- 
tion of  the,  202;  voice  of  the,  602;  monogamous  habits  of  the,  674; 
male,  beard  of  the,  607. 

Oranges,  treatment  of,  by  monkeys,  56. 

Orange  tip  butterfly,  350,  354. 

iyrchestia  Dancinii,  dimorphism  of  males  of,  303 ;  orehestia 
tucuratinga,  limbs  of,  302,  307. 

Ordeal,  trial  by,  108. 

Oreas  canna,  colors  of  612;  oreas  derbianus,  colors  of,  612,  621. 

Organs,  prehensile,  237;  utilized  for  new  purposes,  651. 

Organic  scale,  von  Baer's  definition  of  progress  in,  186. 

Orioles,  nidification  of,  516. 

Oriolus,  species  of,  breeding  in  immature  plumage,  552;  oriolua 
mdanocephalus,  coloration  of  the  sexes  in,  524. 

Ornaments,  prevalence  of  similar,  203;  of  male  birds,  416;  fond- 
ness of  savages  for,  654. 

Ornamental  characters,  equal  transmission  of,  to  both  sexes,  in 
mammals,  619;  of  monkeys,  626. 

Omithoptera  crcesus,  283. 

OrnitJiorynchus,  178  ;  reptilian  tendency  of,  180  ;  spur  of  the 
male,  573. 

Orocetes  erythrogastra,  young  of,  554. 

Orrony,  Grotto  of,  24. 

Orsodacna  aira,  difference  of  color  in  the  sexes  of,  333;  orsodacita 
ruficoUis,  333. 

Orthoptera,  320;  metamorphosis  of,  268;  stridulating  apparatus  of, 
321,  326;  colors  of,  327;  rudimentary  stridulating  organs  in  female, 
326;  stridulation  of  the,  and  Homoptera,  discussed,  327. 

Ortygornis  gulaiis,  pugnacity  of  the  male,  412. 

Oryctes,  stridulation  of,  344;  sexual  differences  in  the  stridulant 
organs  of,  345. 

Oryx  leucoryx,  use  of  the  horns  of,  580,  585.  590. 

Osphranter  rufus,  sexual  difference  in  the  color  of,  609. 

Ostrich,  African,  sexes  and  incubation  of  the,  544. 

Ostriches,  stripes  of  young,  529. 

Otana  jiihata,  mane  of  the  male,  594;  otaj'ia  nigrescens,  difference 
in  the  coloration  of  the  sexes  of,  610. 

Otis  bengalensis,  love-antics  of  the  male,  432;  otis  tarda,  throat- 
pouch  of  the  male,  423;  polygamous,  248. 

Ouzel,  ring,  colors  and  nidification  of  the,  518;  water,  singing  in 
the  autumn,  420;  colors  and  nidification  of  the,  518. 


770  INDEX, 

Ovibos  moscTiatuSy  horns  of,  576. 

Ovi|x>sitor  of  insects,  235. 

Ocw  ct/diKiros,  nunie  of  fighting  of,  579,  585. 

Ovule  of  man,  9. 

Owen,  Pn)f. ,  on  the  CorjK)ra  Woltfiana,  10;  on  the  e^reat  toe  in 
man,  10;  on  the  nictitAting  membrane  and  semilunar  fold,  19;  on  the 
development  of  the  posterior  molars  in  different  races  of  man,  22; 
on  the  length  of  the  caecum  in  the  Koala,  23;  on  the  coccygeal  verte- 
brae, 25;  on  rudimentary  structures  belonging  to  the  reprtxluctive 
system,  20;  on  abnornuil  conditions  of  the  human  uterus,  43;  on  the 
number  of  digits  in  the  Ichthvopt<»rygia.  42;  on  the  canine  teeth  in 
man,  45;  on  the  walking  of  tLe  chimiMinzee  and  orang,  56;  on  the 
mastoid  processes  in  the  higher  aj^es,  59;  on  the  hairiness  of  ele- 
phants in  elevated  districts,  04;  on  the  caudal  vertebrae  of  monkeys, 
65;  cla^sitication  of  nuimmalia,  108;  on  the  hair  in  monkeys,  171;  on 
the  piscine  affinities  of  the  Ichthyosaurians.  180;  on  jx>lygamy  and 
monogamy  among  the  anteloj>es,  246;  on  the  horns  of  AntiitKapra 
ameriaina,  265;  on  the  musky  odor  of  the  cnx'iKliles  during  the 
breeding- season,  398;  on  the  scent  glands  of  snakes,  399;  on  the 
Dugong.  Cachalot  and  Ornit/iorfif/nc/tus,  572,  573;  on  the  antlers  of 
the  red  deer,  582;  on  the  dentition  of  the  Camelid«e,  586;  on  the 
horns  of  the  Irish  elk,  587;  on  the  voice  of  the  giraffe,  porcupine  and 
stag.  600;  on  the  laryngeal  sjic  of  the  gorilla  and  orang,  602;  on  the 
odoriferous  glands  of  mammals.  604,  606;  on  the  effects  of  emascula- 
tion on  the  vocal  organs  of  men.  645;  on  the  voice  of  Hylobat^s 
Uffiliit,  647;  on  American  monogamous  monkeys.  674. 

Owls,  white,  new  mates  found  by,  463. 

Oxi/uotus,  difference  of  the  females  of  two  species  of,  536. 

Pachydermata,  247. 

Parhytylus  migrdtorius.  321. 

Paget,  on  the  abnormal  development  of  hairs  in  man.  20;  on  the 
thickness  of  the  skin  on  the  soles  of  the  feet  of  infants,  37. 

Pagurus,  carrying  the  female.  303. 

Painting,  pleasure  of  savages  in,  203. 

Paltrmon,  chela*  of  a  si>ecies  of,  302. 
•  Palaoriiis,  sexual  differences  of  color  in,  562;  pt^mfmia  jaetmicuty 
color  of  beak  of.  525;  pahrornis  i'(mi,  young  of,  532. 

Palamedea  comutti,  spurs  on  the  wings,  414. 

Palet>lithic  j)eriod,  164, 

Palestine,  habits  of  the  chaffinch  in,  281. 

Pallas,  on  the  i>erfection  of  the  senses  in  the  Mongolians,  38;  on 
the  want  of  connection  between  climate  and  the  color  of  the  skin, 
219;  on  the  ix>lygamous  habiti?  of  Antilopt  Sitiga.  246;  on  the  lighter 
color  of  horses  and  cattle  in  winter  in  Siberia.  260;  on  the  tusks  of 
the  musk-deer,  586;  on  the  odoriferous  glands  of  mammals.  604;  on 
the  odoriferous  glands  of  the  musk-deer,  605;  on  winter  changes 
of  color  in  mammals,  619;  on  the  ideal  of  female  beauty  in  North 
China,  659. 

Palmai-is  aceessorius,  muscle  variations  of  the,  80. 

Pampas,  horses  of  the,  206. 

Pangenesis,  hyix>thesis  of,  258,  261. 

Pannieuius  earnotttis,  14. 

Pausch,  on  the  brain  of  a  foetal  Ctbu9  apeiiay  289. 


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772  INDEX. 

Payaguas  Indians,  thin  legs  and  thick  arms  of  the,  37. 

Payan,  Mr.,  on  the  proportion  of  the  sexes  in  sheep,  279. 

Peacock,  polygamous,  248;  sexual  characters  of,  267;  pugnacity  of 
the,  413;  Javan,  possessing  spurs,  413;  rattling  of  the  quills  by,  426; 
elongated  tail-coverts  of  the,  435,  457;  love  of  display  of  the, 
447,  490;  ocellated  spots  of  the,  489;  inc(mvenience  of  long  tail  of 
the,  to  the  female,  505,  513,  514;  continued  increase  of  beauty 
of  the,  552;  butterfly,  354. 

Peafowl,  preference  of  females  for  a  particular  male,  475;  first 
advances  made  by  the  female,  477. 

Pediculi  of  domestic  animals  and  man,  193. 

Pedigree  of  man,  188. 

Pedionomus  torquatus,  sexes  of,  542. 

Peel,  J.,  on  horned  sheep,  576. 

Peewit,  wing-tubercles  of  the  male,  414. 

Pelagic  animals,  transparency  of,  295. 

Pelecanus  ei'ythrorhynchus,  horny  crest  on  the  beak  of  the  male, 
during  the  breeding-season,  442 ;  pelecanus  onocrotalus,  spring 
plumage  of,  446. 

Pelele,  an  African  ornament,  657. 

Pelican,  blind,  fed  by  his  companions,  116;  young,  guided  by  old 
birds,  116;  pugnacity  of  the  male,  411. 

Pelicans,  fishing  in  concert,  114. 

Pelobius  liermauui,  stridulation  of,  343,  345. 

Pelvis,  alteration  of,  to  suit  the  erect  attitude  of  man,  59;  diflEer- 
ences  of  the,  in  the  sexes  of  man,  635. 

Penelope  nigra,  sound  produced  by  the  male,  429. 

Pennant,  on  the  battles  of  seals,  571;  on  the  bladder-nose 
seal,  603. 

Pentlie,  antennal  cushions  of  the  male,  313. 

Perch,  brightness  of  the  male,  during  breeding-season,  386. 

Peregrine  falcon,  new  mate  found  by,  463. 

Period  of  variability,  relation  of,  to  sexual  selection,  271. 

Periodicity,  vital.  Dr.  Lay  cock  on,  8. 

Periods,  lunar,  followed  by  functions  in  man  and  animals,  8,  187; 
of  life,  inheritance  at  corresponding,  258,  262. 

Perisoreus  canadensis,  young  of,  549. 

Peritrichia,  difference  of  color  in  the  sexes  of  a  species  of,  333. 

Periwinkle,  296. 

Pernis  cristata,  481. 

Perrier,  M.,  on  sexual  selection,  237;  on  bees,  332. 

Perseverance,  a  characteristic  of  man,  644. 

Persians,  said  to  be  improved  by  intermixture  with  Georgians  and 
Circassians,  669. 

Personnat,  M.,  on  Bombyx  Tamamai,  283. 

Peruvians,  civilization  of  the,  not  foreign,  164 

Petrels,  colors  of,  562. 

Petrocincla  cyanea,  young  of,  554. 

Petrocossyphus,  525. 

Petronia,  550. 

Pfeiffer,  Ida,  on  Javan  ideas  of  beauty,  661. 

Phacochcerus  cethiopicus,  tusks  and  pads  of,  592. 

Phalanger,  Vulpine,  black  varieties  of  the,  616. 


INDEX.  *t1t 

PTialaropus  fulicarius,  544;  phaZaropus  Tiyperhoreus,  544. 

PhniKBUs,  338;  phancetis  carnifex,  variation  of  the  hortis  of  the 
male,  336;  phaiKBUs  f annus,  sexual  difference  of,  335;  phancmis 
lancifer,  336. 

Phaseolarctus  cinereus,  taste  for  rum  and  tobacco,  7. 

Phasgaiiura  viridissima,  stridulation  of,  322,  328. 

Phadanus  Scemmerringii,  507;  plmsianus  versicolor,  449;  ph/mantis 
Wallichii,  454,  538. 

Phea-sant,  polygamous,  248;  and  black  grouse,  hybrids  of,  470; 
production  of  hybrids  with  the  common  fowl,  477;  immature 
plumage  of  the,  532;  Amherst,  display  of,  449;  Argus,  435,  526; 
display  of  plumage  by  the  male,  451;  ocellated  spots  of  th£,  488, 
493;  gradation  of  characters  in  the,  493;  blood,  413;  cheer,  454; 
eared,  267,  454,  538;  length  of  the  tail  in  the,  513;  sexes  alike  in 
the,  524  ;  fire- backed,  possessing  spurs,  413 ;  golden,  display  of 
plumage  by  the  male,  449;  age  of  mature  plumage  in  the,  551;  sex 
of  young,*  ascertained  by  pulling  out  head-feathers,  551;  Kalij, 
drumming  of  the  male,  426,  533;  Reeve's,  length  of  the  tail  in,  514; 
silver,  triumphant  male,  deposed  on  account  of  spoiled  plumage, 
476 ,  sexual  coloration  of  the,  560  ;  Soemmerring's,  507,  514 ; 
Tragopan,  434;  display  of  plumage  by  the  male,  451;  marking  of  the 
sexes  of  the,  487. 

Pheasants,  period  of  acquisition  of  male  characters  in  the 
family  of  the,  266;  proportion  of  sexes  in  chicks  of,  280;  length  of 
the  tail  in,  507,  513,  514. 

Philters,  worn  by  women,  659. 

Phoca  gr(B7ilandica,  sexual  difference  in  the  coloration  of,  611. 

PJmnicura  rutieiUa,  464. 

Pliosphorescence  of  insects,  314. 

Phryganidae,  copulation  of  distinct  species  of,  312. 

Phryniscus  nigricans,  396. 

Physical  inferiority,  supposed,  of  man,  67. 

Pickering,  on  the  number  of  species  of  man,  199. 

Picton,  J.  A.,  on  the  soul  of  man,  700. 

Picus  auratus,  411;  picas  major,  456. 

Pieiis,  354,  361. 

Pigeon,  female,  deserting  a  weakened  mate,  242 ;  carrier,  late 
development  of  the  wattle  in,  269;  pouter,  late  deveh)pment  of  the 
crop  in,  269;  domestic,  breeds  and  sub-breeds  of,  523. 

Pigeons,  nestling,  fed  by  the  secretion  of  the  crop  of  both  parents, 
185;  changes  of  plumage  in,  259;  transmission  of  sexual  peculiarities 
in,  261;  Belgian,  with  black-streaked  males,  262,  269,  507;  changing 
color  after  several  moultings,  269;  numerical  proportion  of  the  sexes 
in,  280;  cooing  of,  425;  variations  in  plumage  of,  438;  display  of 
plumage  by  male,  456;  local  memory  of,  467;  antipathy  of  female, 
to  certain  males,  475;  pairing  of,  475;  profligate  male  and  female, 
475;  wing-bars  and  tail-feathers  of,  486;  supposititious  breed  of,  506; 
pouter  and  carrier,  peculiarities  of,  predominant  in  males,  508;  nidifi- 
cation  of,  516;  Australian,  522;  immature  plumage  of  the,  532. 

Pigs,  origin  of  the  improved  breeds  of,  202;  numerical  proportion 
of  the  sexes  in,  279;  stripes  of  young,  529,  623;  tusks  of  miocene, 
593;  sexual  preference  shown  by,  598. 

Pike,  American,  brilliant  colors  of  the  male,  during  the  breeding- 


774  INDEX. 

seasons,  386;  reasoning  powers  of,  85;  male,  devoured  by  females, 
281. 

Pike,  L.  O.,  on  tlie  psychical  elements  of  religion,  108. 

Pimelia  striata,  sounds  produced  by  the  female,  S47. 

Pinel,  hairiness  in  idiots,  41. 

Pintail,  drake,  plumage  of,  446;  pairing  with  a  wild  duck,  471; 
duck,  pairing  with  a  widgeon,  471. 

Pipe-fish,  filamentous,  390;  marsupial  receptacles  of  the  male,  392. 

Pipits,  moulting  of  the,  444. 

Pipra,  modified  secondary  wing-feathers  of  the  male,  429;  pipra 
deliciosa,  429,  430. 

Pirates  stridulus,  stridulation  of,  319. 

Pitcairn  Island,  half-breeds  on,  217. 

Pithecia  leucocepliala,  sexual  differences  of  color  in,  613;  pithecia 
satanas,  beard  of,  607;  resemblance  of,  to  a  negro,  690. 

Pits,  suborbital,  of  Ruminants,  604. 

Pittidse,  nidification  of,  516. 

Placentata,  179. 

Plagiostomous  fishes,  375. 

Plain- wanderer,  Australian,  542. 

PlanaricB,  bright  colors  of  some,  295. 

Plantain-eaters,  colors  and  nidification  of  the,  518;  both  sexes  of, 
equally  brilliant,  523. 

Plants,  cultivated,  more  fertile  than  wild,  50;  Niigeli,  on  natural 
selection  in,  68;  male  flowers  of,  mature  before  the  female,  240; 
phenomena  of  fertilization  in,  251. 

Platalea,  425;  change  of  plumage  in,  525. 

Platyblemnus,  328. 

Platycercus,  young  of,  549. 

Platyphyllam  concavum,  321,  324. 

Platyrrhine  monkeys,  174. 

Platysma  myoides,  14. 

Plecostomus,  head-tentacles  of  the  males  of  a  species  of,  884; 
plecostomus  harhatus,  peculiar  beard  of  the  male,  383. 

Pkctropterus  gambends,  spurred  wings  of,  414 

Ploceus,  420,  426,  460. 

Plovers,  wing-spurs  of,  414,  double  moult  in,  442,  444. 

Plumage,  changes  of,  inheritance  of,  by  fowLs,  259;  tendency  it, 
analogous  variation  in,  438;  display  of,  by  male  birds,  447,  455; 
changes  of,  in  relation  to  season,  526;  immature,  of  birds,  529,  530; 
color  of,  in  relation  to  protection,  556. 

Plumes  on  the  head  in  birds,  differences  of,  in  the  sexes,  513. 

Pneumora,  structure  of,  325. 

Podica,  sexual  difference  in  the  color  of  the  irides  of,  483. 

Poeppig,  on  the  contact  of  civilized  and  savage  races,  208. 

Poison,  avoidance  of,  by  animals,  90. 

Poisonous  fruits  and  herbs  avoided  by  animals,  75. 

Poisons,  immunity  from,  correlated  with  color,  220. 

Polish  fowls,  origin  of  the  crest  in,  261. 

Pollen  and  van  Dam,  on  the  colors  of  Lemur  macaco,  613. 

Polyandry,  677;  in  certain  Cyprinidae,  282;  among  the  Elateridse, 
386. 

Polydactylism  in  man,  42. 


IKDBX.  775 

Polygamy,  influence  of,  upon  sexual  selection,  245;  superinduced 
by  domestication,  249;  supposed  increase  of  female  births  by,  277;  in 
the  stickleback,  376. 

Polygenists,  200. 

Polynesia,  prevalence  of  infanticide  in,  676. 

Polynesians,  wide  geographical  range  of,  33;  difference  of  stature 
among  the,  35;  crosses  of,  198;  variability  of,  198;  heterogeneity  of 
the.  219;  aversion  of,  to  hairs  on  the  face,  662. 

Polyplectron,  number  of  spurs  in,  413;  display  of  plumage  by  the 
mal«,  450;  gradation  of  characters  in,  490,  female  of,  536;  polyplect- 
ron  chinquu,  450,  491 ;  polyplectron  hardwickii,  491  ;  polypleetron 
malac4^^n«e,  491,  492. 

Polyplectron  Napokonis,  490,  492. 

Polvzoa,  296. 

Pomotis,  391. 

Pontoporeia  affinis,  300. 

Porcupine,  mute,  except  in  the  rutting-season,  600. 

Pores,  excretory,  numerical  relation  of,  to  the  hairs  in  sheep,  225. 

PorpitcB,  bright  colors  of  some,  295. 

Portax  picta,  dorsal  crest  and  throat-tuft  of,  606;  sexual  differences 
of  color  in,  611,  612,  621. 

Portuniis  puber,  pugnacity  of,  304. 

Potamocharus  penicillatus,  tusks  and  facial  knobs  of  the,  593, 

Pouchet  U.,  the  relation  of  instinct  to  intelligence,  75;  on  the 
instincts  of  ants,  168;  on  the  caves  of  Abou-Simbel,  191;  on  the 
immunitv  of  negroes  from  vellow  fever,  220;  change  of  color  in 
fishes,  390. 

Pouter-pigeon,  late  development  of  the  large  crop  in,  269. 

Powell,  Dr.,  on  stridulation,  319. 

Power,  Dr.,  on  the  different  colors  of  the  sexes  in  a  species  of 
Squilla,  306. 

Powys,  Mr.,  on  the  habits  of  the  chaflBnch  in  Corfu,  281. 

Pre-eminence  of  man,  54. 

Preference  for  males  by  female  birds,  470, 477;  shown  by  mammals, 
in  pairing,  595. 

Prehensile  organs,  237. 

Presbytis  entellus,  fighting  of  the  male,  641. 

Preyer,  Dr.,  on  function  of  shell  of  ear,  15;  on  supernumerary 
mammae  in  women,  41. 

Prichard,  on  the  difference  of  stature  among  the  Polynesians,  35; 
on  the  connection  between  the  breadth  of  the  skull  in  the  Mongolians 
and  the  perfection  of  their  senses,  38;  on  the  capacity  of  British 
skulls  of  different  ages,  61 ;  on  the  flattened  heads  of  the  Colombian 
savages,  655;  on  Siamese  notions  of  beauty,  659;  on  the  beard lessness 
of  the  Siamese,  663;  on  the  deformation  of  the  head  among  American 
tribes  and  the  natives  of  Arakhan,  665. 

Primary  sexual  organs,  234. 

Primates,  170,  233;  sexual  differences  of  color  in,  613. 

Primogeniture,  evils  of,  153. 

Prionidae,  difference  of  the  sexes  in  color,  333. 

Proctotretns  multimaculatus^  406;  proetotretus  tenuis,  sexual  differ- 
ence in  the  color  of,  406. 

Profligacy,  155. 


1!%  INDEX. 

Progenitors,  early,  of  man,  182. 

Progress,  not  the  normal  rule  in  human  society,  150;  elements 
of,  159. 

Prong-horn  antelope,  horns  of,  265. 

Proportions,  difference  of,  in  distinct  races,  190. 

Protective  coloring  in  butterflies,  353;  in  lizards,  406;  in  birds, 
539,  556;  in  mammals,  619;  nature  of  the  dull  coloring  of  female 
Lepidoptera,  363,  364,  367;  resemblances  in  fishes,  390. 

Protozoa,  absence  of  secondary  sexual  characters  in,  294. 

Pruner-Bey,  on  the  occurrence  of  the  supra-condyloid  foramen  in 
the  humerus  of  man,  24;  on  the  color  of  negro  infants,  636. 

Prussia,  numerical  proportion  of  male  and  female  births  in,  275. 

Psocus,  proportions  of  the  sexes  in,  287. 

Ptarmigan,  monogamous,  248;  summer  and  winter  plumage  of  the, 
443,  444;  nuptial  assemblages  of,  460;  triple  moult  of  the,  526;  pro- 
tective coloration  of,  540. 

Puff-birds,  colors  and  nidification  of  the,  518. 

Pugnacity  of  fine-plumaged  male  birds,  454. 

Pumas,  stripes  of  young,  528. 

Puppies  learning  from  cats  to  clean  their  faces,  82. 

Pycnonotus  hcemorrhous^  pugnacity  of  the  male,  409;  display  of 
under  tail  coverts  by  the  male,  456. 

Pyranga  (Estiva,  male  aiding  in  incubation,  515;  male  characters  in 
female  of,  525. 

Pyrodes,  difference  of  the  sexes  in  color,  333. 

Quadrumana,  hands  of,  56;  differences  between  man  and  the,  170; 
sexual  differences  of  color  in,  612;  ornamental  characters  of,  626; 
analogy  of  sexual  differences  of,  with  those  of  man,  634;  fighting  of 
males  for  the  females,  641;  monogamous  habits  of,  674;  beards  of 
the,  688. 

Quain,  R.,  on  the  variation  of  the  muscles  in  man,  30. 

Quatrefages,  A.  de,  on  the  occurrence  of  a  rudimentary  tail  in  man, 
25;  on  variability,  33;  on  the  moral  sense  as  a  distinction  between 
man  and  aninuls,  110;  civilized  men  stronger  than  savages,  154;  on 
the  fertility  of  Australian  women  with  white  men,  194 ;  on  the 
Paulistas  of  Brazil,  197;  on  the  evolution  of  the  breeds  of  cattle, 
201;  on  the  Jews,  220;  on  the  liability  of  negroes  to  tropical  fevers 
after  residence  in  a  cold  climate,  221;  on  the  difference  between 
field  and  house  slaves,  223;  on  the  influence  of  climate  on  color,  223; 
colors  of  annelids,  299;  on  the  Ainos,  639;  on  the  women  of  San 
Giuliano,  670. 

Quechua,  see  Quichua. 

Querquedula  acuta,  471. 

Quetelet,  proportion  of  sexes  in  man,  275;  relative  size  in  man  and 
woman,  276. 

Quichua  Indians,  38;  local  variation  of  color  in  the,  223;  no  gray 
hair  among  the,  637;  hairlessness  of  the,  640;  long  hair  of  the,  662. 

Quiscalus  major,  255;  proportion  of  the  sexes  of,  in  Florida  and 
Honduras,  281. 

Rabbit,  white  tail  of  the,  619. 

Rabbits,  domestic,  elongation  of  the  skull  in,  63;  modification  of 
the  skull  in,  by  the  lopping  of  the  ear,  63;  danger-signals  of,  114; 
numerical  proportion  of  the  sexes  in.  279. 


INDEX.  777 

Races,  distinctive  characters  of,  190,  191;  or  species  of  man,  191; 
crossed,  fertility  or  sterility  of,  194;  of  man,  variability  of  the,  198; 
of  man,  resemblance  of,  iii  mental  characters,  203;  formation  of,  206; 
of  man,  extinction  of,  206;  effects  of  the  crossing  of,  218;  of  man, 
formation  of  the,  218;  of  man,  children  of  the,  635;  beardless,  aver- 
sion of,  to  hairs  on  the  face,  662. 

Raffles,  Sir  S.,  on  the  banteng,  613. 

Rafts,  use  of,  54,  205. 

Rage,  manifested  by  animals,  77. 

Raia  Ji/xtis,  teeth  of,  379;  raia  clavata,  female  spined  on  the  back, 
375;  sexual  difference  in  the  teeth  of,  379;  raia  maculata,  teeth  of, 
379. 

Rails,  spur- winged,  414. 

Ram,  mode  of  fighting  of  the,  579;  African,  mane  of  an,  608;  fat- 
tailed,  608. 

Rameses  II,  features  of,  192. 

Ramsay,  Mr.,  on  the  Australian  muck-duck,  407;  on  the  regent- 
bird,  470;  on  the  incubation  of  Menura  superba,  513. 

Rana  esculenta,  vocal  sacs  of,  397. 

Rat,  common,  general  dispersion  of,  a  consequence  of  superior 
cunning,  91;  supplantation  of  the  native,  in  New  Zealand,  by  the 
European  rat,  218;  common,  said  to  be  polygamous,  247;  numerical 
proportion  of  the  sexes  in,  279. 

Rats,  enticed  by  essential  oils,  603. 

Rationality  of  birds,  466. 

Rattlesnakes,  difference  of  the  sexes  in  the,  398;  rattles  as  a 
call,  401. 

Raven,  vocal  organs  of  the,  421;  stealing  bright  objects,  469;  pied, 
of  the  Feroe  Islands,  482. 

Rays,  prehensile  organs  of  male,  375. 

Razor-bill,  young  of  the,  553. 

Reade,  Winwood,  suicide  among  savages  in  Africa,  133;  mulattoes 
not  prolific,  195;  effect  of  castration  of  horned  sheep,  577;  on  the 
Guinea  sheep,  266;  on  the  occurrence  of  a  mane  in  an  African  ram, 
608;  on  singing  of  negroes,  652;  on  the  negroes  appreciation  of  the 
beauty  of  their  women,  658;  on  the  admiration  of  negroes  for  a 
black  skin,  660;  on  the  idea  of  beauty  among  negroes,  663;  on  the 
Jollofs,  670;  on  the  marriage-customs  of  the  negroes,  684. 

Rea.son  in  animals,  84. 

Redstart,  American,  breeding  in  immature  plumage,  552. 

Redstarts,  new  mates  found  by,  464. 

Reduvidae,  stridulation  of,  319. 

Reed-bunting,  head-feathers  of  the  male,  455;  attacked  by  a  bull- 
finch, 468. 

Reefs,  fishes  frequenting,  389. 

Reeks,  H.,  retention  of  horns  by  breeding  deer,  574;  cow  rejected 
by  a  bull,  598;  destruction  of  piebald  rabbits  by  cats,  619. 

Regeneration,  partial,  of  lost  parts  in  man,  8. 

Regentrbirds,  470. 

Reindeer,  horns  of  the.  264;  battles  of,  571;  horns  of  the  female, 
574;  antlers  of,  with  numerous  points,  582;  winter  change  of  the, 
619;  sexual  preferences  shown  by,  598. 

Relationship,  terms  of,  675. 


778  INDEX. 

Religion,  deficiency  of  among  certain  races,  106;  psychical  elements 
of,  107. 

Remorse,  129;  deficiency  of,  among  savages,  149. 

Rengger,  on  tbe  diseases  of  Cebus  AzarcB,  7;  on  the  diversity  of 
the  mental  faculties  of  monkeys,  31;  on  tbe  Payaguas  Indians,  37; 
on  the  inferiority  of  Europeans  to  savages  in  their  senses,  38;  revenge 
taken  by  monkeys,  78;  on  maternal  affection  in  a  Cebus,  79;  on  the 
reasoning  powers  of  American  monkeys,  87;  on  the  use  of  stones  by 
monkeys  for  cracking  hard  nuts,  91;  on  the  sounds  uttered  by  Cebus 
Azarcel  95;  on  the  signal-cries  of  monkeys,  98;  on  the  polygamous 
habits  of  Mycetes  car  ay  a,  246;  on  the  voice  of  the  howling  monkeys, 
602;  on  the  odor  of  Cervus  campcstris,  604;  on  the  beards  of  Mycetes 
caraya  and  Pithecia  Satanas,  607;  on  the  colors  of  Felis  mitis,  610; 
on  the  colors  of  Cervus  paludosus,  613;  on  sexual  differences  of  color 
in  Mycetes,  613;  on  the  color  of  the  infant  Guaranys,  636;  on  the 
early  maturity  of  the  female  of  Cehes  Azarcp,  636;  on  the  beards  of  the 
Guaranys,  639;  on  the  emotional  notes  employed  by  monkeys,  652; 
on  American  polygamous  monkeys,  674. 

Representative  species,  of  birds,  533. 

Reproduction,  unity  of  phenomena  of,  throughout  the  mammalia, 
8;  period  of,  in  birds,  551. 

Reproductive  system,  rudimentary  structures  in  the,  26;  accessory 
parts  of,  183. 

Reptiles,  397. 

Reptiles  and  birds,  alliance  of,  188. 

Resemblances,  small,  between  man  and  the  apes,  171. 

Retrievers,  exercise  of  reasoning  faculties  by,  88. 

Revenge,  manifested  by  animals,  78. 

Reversion,  41 ;  perhaps  the  cause  of  some  bad.  dispositions,  155. 

Rhagium,  difference  of  color  in  the  sexes  of  a  species  of,  333. 

Rhamphastos  carinatus,  560. 

Rhea  Darwinii,  545. 

Rhinoceros,  nakedness  of,  64;  horns  of,  576;  horns  of,  used  defens- 
ively, 590;  attacking  white  or  gray  horses,  617. 

RJiynchcBa,  sexes  and  young  of,  543 ;  rhynclioBa  australis,  543; 
rhynchma  bengalensis,  543;  rhynchma  capensis,  543. 

Rhythm,  perception  of,  by  animals,  649. 

Richard,  M.,  on  rudimentary  muscles  in  man,  13. 

Richard,  Sir  J.,  on  the  pairing  of  Tetrao  umbellus,  416;  on  Tetrno 
urophasiarms,  423;  on  the  drumming  of  grouse,  423,  427;  on  the 
dances  of  Tetrao  phasianellus,  431;  on  assemblages  of  grouse,  460; 
on  the  battles  of  male  deer,  571;  on  the  reindeer,  574;  on  the  horns 
of  the  musk-ox,  576 ;  on  antlers  of  the  reindeer  with  numerous 
points,  582;  on  the  moose,  587;  on  the  Scotch  deerhound,  589. 

Richter,  Jean  Paul,  on  imagination,  84. 

Riedel,  on  profligate  female  pigeons,  475. 

Riley,  Mr.,  on  mimicry  in  butterflies,  367;  bird's  disgust  at  taste  of 
certain  caterpillars,  370. 

Ring-ouzel,  colors  and  nidification  of  the,  518. 

Ripa,  Father,  on  the  difficulty  of  distinguishing  the  races  of  the 
Chinese,  190. 

Rivalry,  in  singing,  between  male  birds,  419. 

Kiver-hog,  African,  tusks  and  knobs  of  the,  598. 


INDEX.  779 

Rivers,  analogy  of,  to  islands,  181. 

Koacb,  briglitness  of  the  male  during  breeding-season,  386. 

Robbery,  of  strangers,  considered  honorable,  133. 

Rol>ertson,  Mr.,  remarks  on  the  development  of  the  horns  in  the 
roebuck  and  red-deer,  265. 

Robin,  pugnacity  of  the  male,  408;  autumn  song  of  the,  420; 
female  singing  of  the,  420;  attacking  other  birds  with  red  in  their 
plumage,  408;  young  of  the,  547. 

Robinet,  on  the  difference  of  size  of  the  male  and  female  cocoons 
of  the  silk-moth,  315. 

Rodents,  uterus  in  the,  43;  absence  of  secondary  sexual  characters 
in,  247;  sexual  differences  in  the  colors  of,  609. 

Roe,  winter  changes  of  the,  619. 

Rohfs,  Dr.,  Caucasian  features  in  negro,  190;  fertility  of  mixed 
races  in  Sahara,  195;  colors  of  birds  in  Sahara,  557;  ideas  of  beauty 
among  the  Bornuans,  663. 

RoUe,  F.,  on  the  origin  of  man,  3;  on  a  change  in  German  families 
settled  in  Georgia,  223. 

Roller,  harsh  cry  of,  421. 

Romans,  ancient,  gladiatorial  exhibitions  of  the,  139. 

Rook,  voice  of  the,  426. 

Rossler,  Dr. ,  on  the  resemblance  of  the  lower  surface  of  butterflies 
to  the  bark  of  trees,  353. 

Rostrum,  sexual  difference  in  the  length  of,  in  some  weevils,  235. 

Royer,  Madlle.,  mammals  giving  suck,  186. 

Rudimentary  organs,  12;  origin  of,  26. 

Rudiments,  presence  of,  in  languages,  102. 

Rudolphi,  on  the  want  of  connection  between  climate  and  the  color 
of  the  skin,  219. 

Ruff,  supposed  to  be  polygamous,  248;  proportion  of  the  sexes  in 
the,  280;  pugnacity  of  the,  409;  double  moult  in,  443,  445;  duration 
of  dances  of,  460;  attraction  of  the,  to  bright  objects,  469. 

Ruminants,  male,  disappearance  of  canine  teeth  in,  60,  641  ; 
generally  polygamous,  246;  suborbital  pits  of,  604;  sexual  differences 
of  color  in,  6il. 

Rupicola  crocea,  display  of  plumage  by  the  male,  448. 

Riippell,  on  canine  teeth  iu  deer  and  antelopes,  586. 

Russia,  numerical  proportion  of  male  and  female  births  in, 
243.  275. 

Euticilla,  525. 

RQtmeyer,  Prof.,  on  the  physiognomy  of  the  apes,  60;  on  tusks  of 
miocene  boar,  593;  on  the  sexual  differences  of  monkeys,  640. 

Rutlandshire,  numerical  proportion  of  male  and  female  births 
in,  274. 

Sachs,  Prof. ,  on  the  behavior  of  the  male  and  female  elements  in 
fertilization,  252. 

Sacrifices,  human,  108. 

Sagittal  crest  in  male  apes  and  Australians,  636. 

Sahara,  fertility  of  mixed  races  in,  195;  birds  of  the,  519;  animal 
inhabitants  of  the,  557. 

Sailors,  growth  of,  delayed  by  conditions  of  life,  34  ;  long- 
sighted, 38. 

Sailors  and  soldiers,  difference  in  the  proportions  of,  36. 


•J'SO  INDEX. 

St.  John,  Mr.,  on  the  attacliraent  of  mated  birds,  466. 

St.  Kilda,  beards  of  the  inhabitants  of,  638. 

Siilmo  eriox  and  S.  umbla,  coloring  of  the  male,  during  the  breed- 
ing-season, 386. 

Halmo  lycaodoii,  378;  8<ilmo  solar,  377. 

Salmon,  leaping  out  of  fresh  water,  122;  male,  ready  to  breed 
before  the  female,  240;  proportion  of  the  sexes  in,  282;  male,  pug- 
nacity of  the,  377;  male,  characters  of,  during  the  breeding-season, 
377,  386;  spawning  of  the,  390;  breeding  of  immature  male,  552. 

Salvin,  O.,  inheritance  of  mutilated  feathers,  67,  436,  689;  on  the 
humming-birds,  248,  516;  on  the  numerical  proportion  of  the  sexes 
in  humming-birds,  281,  555;  on  Chamo'petes  and  Penelope,  429;  on 
Selaspharus  platycercus,  429;  Pipra  deliciosa,  429;  on  (Jhasmorhyn- 
chus,  442. 

Samoa  Islands,  beardlessness  of  the  natives  of,  639,  663. 

Sandhoppers,  claspers  of  male,  307. 

Sand-skipper,  305. 

Sandwich  Islands,  variation  in  the  skulls  of  the  natives  of  the^  29; 
decrease  of  native  population,  211;  population  of,  290;  superiority  of 
the  nobles  in  the,  669;  Islanders,  lice  of,  193. 

San-Giuliano,  women  of,  670. 

Santali,  recent  rapid  increase  of  the,  51;  Mr.  Hunter  on  the,  218. 

Saphirina,  characters  of  the  males  of,  306. 

Sarkidiornis  irielanonotus,  characters  of  the  young,  529. 

Sars,  O.,  on  Pontoporeia  affinis,  300. 

Saturnia  carpitii,  attraction  of  males  by  the  female,  284;  saturnia 
lo,  difference  of  coloration  in  the  sexes  of,  358. 

Saturniidm,  coloration  of  the,  356,  358. 

Savage,  Dr.,  on  the  fighting  of  the  male  gorillas,  641;  on  the  habits 
of  the  gorilla,  675. 

Savage  and  Wyman  on  the  polygamous  habits  of  the  gorilla,  246. 

Savages,  uniformity  of,  exaggerated,  32;  long-sighted,  37;  rate  of 
increase  among,  usually  small,  50;  retention  of  the  prehensile  power 
of  the  feet  by,  58;  imitative  faculties  of,  98,  146;  causes  of  low 
morality  of,  135;  tribes  of,  supplanting  one  another,  145;  improve- 
ments in  the  arts  among,  164;  arts  of,  203;  fondness  of,  for  rough 
music,  431;  on  long-enduring  fashions  among,  563;  attention  paid 
by,  to  personal  appearance,  654;  relation  of  the  sexes  among,  675. 

Saviotti,  Dr.,  division  of  malar  bone,  44. 

Saw-fly,  pugnacity  of  a  male,  330. 

Saw-llies,  proportions  of  the  sexes  in,  286. 

Saxicola  rubicola,  young  of,  555. 

Scalp,  motion  of  the,  14. 

Scent-glands  in  snakes,  399. 

Schaaffhausen,  Prof.,  on  the  development  of  the  posterior  molars 
in  different  races  of  man,  22;  on  the  jaw  from  La  Naulette,  46;  on 
the  correlation  between  muscularity  and  prominent  supraorbital 
ridges,  49;  on  the  mastoid  processes  of  man,  59;  on  modifications  of 
the  cranial  bones,  62;  on  human  sacrifices,  163;  on  the  probable 
speedy  extermination  of  the  anthropomorphous  apes,  178;  on  the 
ancient  inhal)itants  of  Europe,  207;  on  the  effects  of  use  and  disuse 
of  ])arts,  225,  on  the  superciliary  ridge  in  man,  634;  on  the  absence 
of  race  differences  in  the  infant  skull  in  man,  635;  on  ugliness,  666. 


INDEX,  781 

Scbaum,  H,,  on  the  elytra  of  Dytiscus  and  Hydnrporus,  313. 

Scherzer  and  Scliwarz,  measurements  of  savages,  038. 

Schelver,  on  dragon -flies,  329. 

Schiodte,  on  the  stridulation  of  Heterocerua,  343. 

Schlegel,  h\  von,  on  the  complexity  of  the  languages  of  uncivilized 
peoples,  103. 

Schlegel,  Prof.,  on  Tanysiptera,  533. 

Schleicher,  Prof.,  on  the  origin  of  language,  98. 

Schomburgk,  Sir  R.,  on  the  pugnacity  of  the  male  musk-duck  of 
Guiana,  411;  on  the  courtship  of  Rupicula  crocea,  448. 

Schoolcraft,  Mr.,  on  the  difficulty  of  fashioning  stone  imple- 
ments, 55. 

Schopenhauer,  on  importance  of  courtship  to  mankind,  669. 

Schweinfurth,  complexion  of  negroes,  634. 

Scicena  aguila,  394. 

Sclater,  P.  L.,  on  modified  secondary  wing-feathers  in  the  males  of 
Pipra,  429,  430 ;  on  elongated  feathers  in  nightjars,  436  ;  on  the 
species  of  G hasmorhynchus,  442;  on  the  plumage  of  Pelecanus 
onocrotaius,  446;  on  the  plantain-eaters,  523;  on  the  sexes  and  young 
of  T'adorna  vanegata,  546;  on  the  colors  of  Lemur  macaco,  613;  on 
the  stripes  in  asses,  626. 

Scolecida,  absence  of  secondary  sexual  characters  in,  294. 

Scolopax  frenata,  tail  -  feathers  of,  428;  scolopax  gallinago, 
drumming  of,  427;  scolopax  javensis,  tail-feathers  of,  428;  scolopax 
maj(/r,  assemblies  of,  460;  scolopax  icilsonii,  sound  produced  by,  428. 

Scolytus,  stridulation  of,  342. 

Scoter-duck,  black,  sexual  difference  in  coloration  of  the,  559 ; 
bright  beak  of  male,  559. 

Scott,  Dr.,  on  idiots  smelling  their  food,  41. 

Scott,  J. ,  on  the  color  of  the  beard  in  man,  637. 

Scrope,  on  the  pugnacity  of  the  male  salmon,  377;  on  the  battles 
of  stags,  571. 

Scudder,  S.  H.,  imitation  of  the  stridulation  of  the  Orthoptera, 
321;  on  the  stridulation  of  the  Acridiidae,  324;  on  a  Devonian  insect, 
327;  on  stridulation,  646. 

Sculpture,  expression  of  the  ideal  of  beauty  by,  663. 

Sea-anemones,  bright  colors  of,  294. 

Sea-bear,  polygamous,  247. 

Sea-elephant,  male,  structure  of  the  nose  of  the,  603;  polygamous, 
247. 

Sea-lion,  polygamous,  247. 

Seal,  bladder-nose,  603. 

Seals,  their  sentinels  generally  females,  114;  evidence  furnished 
by,  on  classification,  170;  polygamous  habits  of,  247;  battles  of  male, 
570;  canine  teeth  of  male.  572;  sexual  differences,  588  ;  pairing  of, 
596;  sexual  peculiarities  of,  603;  in  the  coloration  of,  610;  apprecia- 
tion of  music  by,  649. 

Sea-scorpion,  sexual  differences  in,  381. 

Season,  changes  of  color  in  birds,  in  accordance  with  the,  442; 
changes  of  plumage  of  birds  in  relation  to,  526. 

Sea.sons,  inheritance  at  corresponding,  259. 

Sebituani,  African  chief,  trying  to  alter  a  fashion,  656. 

Sebright  Bantam,  270. 


782  INDEX, 

Secondary  Rexual  characters,  284;  relations  of  jwlygainy  to,  245, 
transmitted  through  both  sexes,  255;  gradation  of,  in  birds,  488. 

iSedgwick,  VV.,  on  her«.'ditary  tendency  to  pnxluce  twins,  51. 

Seeniann,  Dr.,  on  the  different  appreciation  of  music  by  different 
peoples,  650;  on  the  effects  of  music,  651. 

Seldlitz,  on  horns  of  reindeer,  577. 

JSeUmp/iorutf  platycereuti,  acuminate  first  primary  of  the  male,  429. 

fcfelby,  P.  J.,  on  the  habits  of  the  black  and  red  grouse,  248. 

Selection,  as  applied  to  primeval  man,  'A2;  double,  255;  injurious 
forms  of,  in  civilized  nations,  152;  of  male  by  female  birds,  459,  477; 
methodical,  of  Prussian  grenadiers,  32;  sexual,  explanation  of,  236, 
241,  249;  influence  of,  on  the  coloring  of  Lepidoptera,  363;  sexual 
and  natural,  contrasted,  256. 

Self-command,  habit  of,  inherited,  131;  estimation  of,  134. 

Self -consciousness,  in  animals,  93. 

Self-preservation,  instinct  of,  127. 

Self-sacrifice,  by  savages,  126;  estimation  of,  134. 

Semilunar  fold,  19. 

iSemnopitheeux,  175;  long  hair  on  the  heads  of  species  of,  171, 
689;  semnopithecuit  chrymymdas,  sexual  differences  of  color  in,  614; 
semnopithtcuH  a/inatuH,  ornamental  hair  on  the  head  of,  627;  nemnopi- 
thecus  frontatug,  beard,  etc.,  of,  629;  tiemnopithecnit  nadca,  nose  of, 
171;  semnopithecus  nemomis,  coloring  of ,  629;  gemnopithecus  rubicMn- 
duM,  ornamental  hair  on  the  head  of,  625. 

Senses,  inferiority  of  Europeans  to  savages  in  the,  38. 

Sentinels,  among  animals,  114,  121. 

Serpents,  instinctively  dreaded  by  apes  and  monkeys,  75,  80. 

SerranuH,  hermaphroditism  in,  184. 

Setina,  noise  produced  by,  349. 

Sex,  inheritance  limited  by,  260. 

Sexes,  relative  proportions  of,  in  man,  274,  636;  proportions  of, 
sometimes  influenced  by  selection,  288;  probable  relation  of  the,  in 
primeval  man,  674. 

Sexual  and  natural  selection,  contrasted,  256;  characters,  effects  of 
the  loss  of,  261;  limitation  of,  262;  characters,  secondary,  234;  rela- 
tions of  polygamy  to,  245;  transmitted  through  both  sexes,  255; 
gradation  of,  in  birds,  488. 

Sexual  differences  in  man,  8;  selection,  explanation  of,  236,  241, 
249;  influence  of,  on  the  coloring  of  Lepidoptera,  363;  objections  to, 
563;  action  of,  in  mankind,  679;  selection  in  spiders,  307;  selection, 
supplemental  note  on,  709;  similarity,  288. 

Shaler,  Prof.,  sizes  of  sexes  in  whales,  588. 

Shame,  129. 

Sharks,  prehensile  organs  of  male,  375. 

Sharpe,  Dr.,  Europeans  in  the  tropics,  222. 

Sharpe,  R.  B.,  on  Tanyidptera  sylmn,  514;  on  Ceryle,  520;  on  the 
young  male  of  Dacelo  Gaudichaudi,  532. 

Shaw,  Mr,,  on  the  pugnacity  of  the  male  salmon,  377. 

Shaw,  J.,  on  the  decorations  of  birds,  434. 

Sheep,  danger-signals  of,  114;  sexual  differences  in  the  horns  of, 
260;  horns  of,  266,  576;  domestic,  sexual  differences  of.  late  devel- 
oped, 269;  numerical  proportion  of  the  sexes  in,  279;  inheritance  of 
horns  by  one  sex,  576;  effect  of  castration,  577;  mode  of  fighting  of, 


INDEX.  783 

579;  arched  foreheads  of  some,  608;  merino,  loss  of  horns  in  females 
of.  201;  horns  of,  266. 

Sliells,  difference  in  form  of,  in  inale  and  female  GaHteropoda,  297; 
beautiful  colors  and  shapes  of,  298. 

Shield  drake,  pairing  with  a  common  duck,  471;  New  Zealand, 
sexes  and  youn^  of,  546. 

8ho<iter,  J.,  on  the  Kaffirs,  661;  on  the  marriage-customs  of  the 
Kaffirs,  661. 

Shrew-mice,  odor  of,  604. 

Shrike,  Drongo,  524. 

Shrikes,  characters  of  young,  529. 

Shuckard,  W.  E.,  on  sexual  differences  m  the  wings  of  Hymenop- 
tera,  314. 

SLiyness  of  adorned  male  birds,  457. 

Siagoniam,  proportions  of  the  sexes  in,  286;  dimorphism  in  males 
of,  889. 

Siam,  proportion  of  male  and  female  births  in,  277. 

Siamese,  general  beard le.ssness  of  the,  639;  notions  of  beauty  of 
the,  660.  hairy  family  of.  687. 

Sidgwick,  11.,  on  morality  in  hypothetical  bee  community,  113;  our 
actions  not  entirely  directed  by  pain  and  pleasure.  136. 

Siel)o]d,  (',  T.  von,  on  the  ])roportion  of  sexes  in  the  ApU8,  287;  on 
the  auditory  apparatus  of  the  stridulant  Orthoptera,  321. 

Sight,  inheritance  of  long  and  short,  88. 

Signal -cries  of  monkeys,  98. 

Silk-moth,  proportion  of  the  sexes  in.  282,  284;  A'Uanthtcs,  Prof. 
Canestrini,  on  the  destruction  of  its  larva)  by  wasps,  284;  difference 
of  size  of  the  male  and  female  cocoons  of  the,  315;  pairing  of 
the.  360. 

Siraiadae,  178;  their  origin  and  divisions,  188. 

Similarity,  sexual,  254. 

Singing,  of  the  Cicadte  and  Fulgoridae,  319;  of  tree-frogs,  897;  of 
birds,  object  of  the,  417. 

SirenUi,  nakedness  of,  68. 

Sirex  juveruius,  831. 

Siricitfae,  difference  of  the  sexes  in,  881. 

Siskin,  446;  pairing  with  a  canary,  472. 

Sitnna,  throat-pouch  of  the  males  of,  402,  406. 

Size,  relative,  of  the  sexes  of  insects,  815. 

Skin,  dark  color  of,  a  protection  against  heat,  228. 

Skin,  movement  of  the,  14;  nakedness  of,  in  man,  68;  color  of 
the,  219;  and  hair,  correlation  of  color  of,  225. 

Skull,  variation  of,  in  man,  29;  cubic  contents  of,  no  absolute  test 
of  intellect,  61;  Neanderthal,  capacity  of  the,  61;  causes  of  modifica 
tion  of  the,  62;  difference  of,  in  form  and  capacity,  in  different  races 
of  men,  192;  variability  of  the  shape  of  the,  198;  differences  of,  in 
the  sexes  in  man,  635;  artificial  modification  of  the  shape  of,  655. 

Skunk,  odor  emitted  by  the,  603;  white  tail  of,  protective,  621. 

Slavery,  prevalence  of,  133;  of  women,  677. 

Slaves,  difference  l)etween  tichl  and  house-slaves,  224. 

Sloth,  ornaments  of  male.  610. 

Smell,  sense  of,  in  man  and  animals,  19. 

j^mith,  Adam,  on  the  basis  of  syinpathy,  120. 


784  INDEX. 

Smith,  Sir  A.,  on  the  recognition  of  women  by  male  Cynocepliali, 
9;  on  revenge  by  a  baboon,  78;  on  an  instance  of  memory  in  a 
baboon,  83;  on  the  retention  of  their  color  by  the  Dutch  in  South 
Africa,  219;  on  the  polygamy  of  the  South  African  antelopes,  246; 
on  the  polygamy  of  the  lion,  247;  on  the  proportion  of  the  sexes  in, 
Kohus  ellipsij^rymnus.  279;  on  BucephnluH  capensis,  398;  on  South 
African  lizards,  406;  on  fighting  gnus.  571;  on  the  horns  of  rhinoce- 
roses, 576;  on  the  fighting  of  lions,  594;  on  the  colors  of  the  Cape 
eland,  612;  on  the  colors  of  the  gnu,  612;  on  the  Hottentot  notions 
of  beauty,  660;  disbelief  in  communistic  marriages,  671 

Smith,  F.,  on  the  Cynipidae  and  Tenthredinidae,  286;  on  the  rela- 
tive size  of  the  sexes  of  Aculeate  Hymenopetra,  316;  on  the  difference 
between  the  sexes  of  ants  and  bees,  331;  on  the  stridulation  of  Trox 
sabulosus,  343;  on  the  stridulation  of  Moiionychus  pseudacori,  345. 

Smynthurus  luteus,  courtship  of,  317. 

Snakes,  sexual  differences  of,  398;  mental  powers  of,  399;  male, 
ardency  of,  399. 

"  Snarling  muscles,"  46. 

Snipe,  drumming  of  the,  427;  coloration  of  the,  558;  painted, 
sexes  and  young  of,  542;  solitary,  assemblies  of,  461. 

Snipes,  arrival  of  male  before  the  female,  240;  pugnacity  of  male, 
411;  double  moult  in,  442. 

Snow-goose,  whiteness  of  the,  560. 

Sociability,  the  sense  of  duty  connected  with.  111;  impulse  to,  in 
animals,  119,  manifestations  of,  in  man,  123;  instinct  of,  in  ani- 
mals, 124. 

Social  animals,  affection  of,  for  each  other,  115,  defense  of,  by  the 
males,  121. 

Sociality,  probable,  of  primeval  men,  70;  influence  of,  on  the  de- 
velopment of  the  intellectual  faculties,  146;  origin   of,  in   man,  147, 

Soldiers,  American,  measurements  of,  34;  and  sailors,  difference  in 
the  proportions  of,  36, 

Solenostoma,  bright  colors  and  marsupial  sac  of  the  females 
of,  393 

Song,  of  male  birds  appreciated  by  their  females,  104;  want  of,  in 
brilliant  plumaged  birds,  454;  of  birds,  512. 

Sorex,  odor  of,  603. 

Sounds,  admired  alike  by  man  and  animals,  104;  produced  by 
fishes,  393;  produced  by  male  frogs  and  toads,  397;  instrumentally 
produced  by  birds,  426  et  seq. 

Spain  decadence  of,  160. 

SparassuH  smaragdidus,  difference  of  color  in  the  sexes  of,  307. 

Sparrow,  pugnacity  of  the  male,  409;  acquisition  of  the  linnet's 
song  by  a,  420;  coloration  of  the,  539;  immature  ])lumage  of  the, 
532;  white-crowned,  young  of  the,  553. 

Sparrows,  house  and  tree,  518,  550;  new  mates  found  by,  463; 
sexes  and  young  of,  550;  learning  to  sing,  651. 

Spathura  Underiroodi,  440. 

Spawning  of  fishes,  387,  391. 

Spear,  used  before  dispersion  of  man,  204. 

Species,  causes  of  the  advancement  of,  156;  distinctive  characters 
of,  190;  or  races  of  man,  191;  sterility  and  fertility  of,  when 
crossed,  194;  supposed,  of  man,  198;  gradation  of,  198;  difficulty  of 


INDEX,  785 

defining,  199;  representative,  of  birds,  533;  of  birds,  comparative 
differences  between  the  sexes  of  distinct,  534. 

Spectrum  femaratum,  difference  of  color  in  the  sexes  of,  328. 

Speech,  connection  between  the  brain  and  the  faculty  of,  99;  con- 
nection of  intonation  with  music,  653. 

"  Spel  "  of  the  black-cock,  425. 

Spencer,  Herbert,  on  the  influence  of  food  on  the  size  of  the  jaws, 
37;  on  the  dawn  of  intelligence,  75;  on  the  origin  of  the  belief  in 
spiritual  agencies,  106;  on  the  origin  of  the  moral  sense,  139;  on 
music,  652,  653. 

Spengel,  disagrees  with  explanation  of  man's  hairlessness,  687. 

Sperm-whales,  battles  of  male,  570. 

Sphingidae,  coloration  of  the,  356. 

Sphinx,  humming-bird,  359;  Mr.  Bates  on  the  caterpillar  of  a,  369. 

Sphinx  moth,  musky  odor  of,  349. 

Spiders,  307;  parental  feeling  in,  120;  male,  more  active  than 
female,  250;  proportion  of  the  sexes  in,  287;  secondary  sexual  char- 
acters of,  308;  courtship  of  male,  308;  attracted  by  music,  309;  male, 
small  size  of,  308. 

SpUosoma  mentJiastri,  rejected  by  turkeys,  358. 

Spine,  alteration  of,  to  suit  the  erect  attitude  of  man,  59. 

Spirits,  fondness  of  monkeys  for,  7. 

Spiritual  agencies,  belief  in,  almost  universal,  106. 

Spiaa  cyanea  and  cirU,  468. 

Spoonbill,  425;  Chinese,  change  of  plumage  in,  525. 

Spots,  retained  tliroughout  groups  of  birds,  485;  disappearance  of, 
in  adult  mammals,  623. 

Sprengel,  C.  K.,  on  the  sexuality  of  plants,  240. 

Spring-boc,  horns  of  the,  580. 

Sproat,  Mr.,  on  the  extinction  of  savages  in  Vancouver  Island,  208; 
on  the  eradication  of  facial  hair  by  the  natives  of  Vancouver  Island, 
662;  on  the  eradication  of  the  beard  by  the  Indians  of  Vancouver 
Island,  689. 

Spurs,  occurrence  of,  in  female  fowls,  257,  261;  development  of, 
in  various  species  of  Phasianidae,  267;  of  Gallinaceous  birds,  412, 
413;  development  of,  in  female  Gallinaceae,  511. 

SquUla,  different  colors  of  the  sexes  of  a  species  of,  306. 

Squirrels,  battles  of  male,  570;  African,  sexual  differences  in  the 
coloring  of,  609;  black,  616. 

Stag,  long  hairs  of  the  throat  of,  595;  horns  of  the,  257,  260; 
battles  of,  571;  horns  of  the,  with  numerous  branches,  581;  bellow- 
ing of  the,  601;  crest  of  the,  606;  beetle,  numerical  proportion  of 
sexes  of,  286;  use  of  jaws,  312;  large  size  of  male,  316;  weapons  of 
the  male,  339. 

Stainton,  H.  T.,  on  the  numerical  proportion  of  the  sexes  in  the 
smaller  moths,  283;  habits  of  Klachistn  rufocinerea,  284  ;  on  the 
coloration  of  moths,  357;  on  the  rejection  of  SpUosoma  meiithastri  hj 
turkeys,  358;  on  the  sexes  of  Agrotis  exclamatimiis,  358. 

Staley,  Bishop,  mortality  of  infant  Maories,  213.  ^ 

Stallion,  mane  of  the,  594. 

Stallions,  two,  attacking  a  third,  115;  fighting,  571;  small  canine 
teeth  of,  586. 

Stansbury,  Capt.,  observations  on  pelicans,  116. 


786  INDEX, 

Staphylinidae,  hornlike  processes  in  male,  338. 

Starfishes,  parental  feeling  in,  120;  bright  colors  of  some,  295. 

Stark,  Dr.,  on  the  death-rate  in  towns  and  rural  districts,  157;  on 
the  influence  of  marriage  on  mortality,  158;  on  the  higher  mortality 
of  males  in  Scotland,  275. 

Starling,  American  field,  pugnacity  of  male,  417  ;  red-winged, 
selection  of  a  mate  by  the  female,  472. 

Starlings,  three,  frequenting  the  same  nest,  248,  464;  new  mates 
found  by,  464. 

Statutes,  Greek,  Egyptian,  Assyrian,  etc.,  contrasted,  663. 

Stature,  dependence  of,  upon  local  influences,  34. 

Staudinger,  Dr.,  on  breeding  Lepidoptera,  284;  his  list  of  Lepidop- 
tera,  284. 

Staunton,  Sir  G.,  hatred  of  indecency  a  modern  virtue,  135. 

Stealing  of  bright  objects  by  birds,  469. 

Stebbing,  T.  R. ,  on  the  nakedness  of  the  human  body,  685. 

Stemmatopus,  603. 

Stendhal,  see  Bombet. 

Stenohothrun  pratorum,  stridulation,  324. 

Stephen,  Mr.  L.,  on  the  difference  in  the  minds  of  men  and 
animals,  88;  on  general  concepts  in  animals,  100;  distinction  between 
material  and  formal  morality,  125. 

Sterility,  general,  of  sole  daughters,  153;  when  crossed,  a  dis- 
tinctive character  of  species,  189  ;  under  changed  conditions 
215,  217. 

Sterna,  seasonal  change  of  plumage  in,  561. 

Stickle-back,  polygamous,  249;  male,  courtship  of  the,  376;  male, 
brilliant  coloring  of,  during  the  breeding-season,  386.  nidification  of 
the,  391. 

Sticks  used  as  implements  and  weapons  by  monkeys,  91. 

Sting  in  bees,  235. 

Stokes,  Capt.,  on  the  habits  of  the  great  bower-bird,  434. 

Stoliczka,  Dr.,  on  colors  in  snakes,  399. 

Stoliczka,  on  the  pre-anal  pores  of  lizards,  402. 

Stonechat,  young  of  the,  555. 

Stone  implements,  difficulty  of  making,  55;  as  traces  of  extinct 
tribes,  206. 

Stones,  used  by  monkeys  for  breaking  hard  fruits  and  as  missiles, 
56;  piles  of,  204. 

Stork,  black,  sexual  differences  in  the  bronchi  of  the,  425;  red 
beak  of  the,  559. 

Storks,  559,  562;  sexual  difference  in  the  color  of  the  eyes  of,  483. 

Strange,  Mr.,  on  the  satin  bower-bird,  434. 

Strepsiceros  kudu,  horns  of,  583;  markings  of,  621. 

Stretch,  Mr.,  on  the  numerical  proportions  in  the  sexes  of 
chickens,  280. 

Stridulation,  by  males  of  TheHdion,  309;  of  Homiptera,  319;  of 
the  Orthoptera  and  Homoptera  discussed,  327;  of  beetles,  341. 

Stripes,  retained  throughout  groups  of  birds,  485;  disappearance 
of,  in  adult  mammals,  624. 

Strix  jlammea,  463. 

Structure,  existence  of  unserviceable  modifications  of,  6§. 

Struggle  for  existence,  in  man,  161,  166. 


INDEX,  787 

Strutbers,  Dr. ,  on  the  occurrence  of  the  supra-condyloid  foramen 
in  the  humerus  of  man,  23. 

SturneUa  ludoviciana,  pugnacity  of  the  male,  417. 

Sturiius  vulgaris,  464. 

Sub-species,  199. 

Suffering,  in  strangers,  indifference  of  savages  to,  133. 

Suicide,  155;  formerly  not  regarded  as  a  crime,  132;  rarely  prac- 
ticed among  the  lowest  savages,  133. 

Suidse,  stripes  of  young,  529. 

Sulivan,  Sir  B.  J.,  on  speaking  of  parrots,  96;  on  two  stallions 
attacking  a  third,  571. 

Sumatra,  compression  of  the  nose  by  the  Malays  of,  665. 

Sumner,  Archb.,  man  alone  capable  of  progressive  improve- 
ment, 89. 

Sun-birds,  nidification  of,  517. 

Superciliary  ridge  in  man,  634,  636. 

Supernumerary  digits,  more  frequent  in  men  than  in  women,  253; 
inheritance  of,  262;  early  development  of,  268. 

Superstitions,  164;  prevalence  of,  138. 

Superstitious  customs,  108. 

Supra-condyloid  foramen  in  the  early  progenitors  of  man,  182. 

Suspicion,  prevalence  of,  among  animals,  78. 

Swallow-tail  butterfly,  354. 

Swallows  deserting  their  young,  122,  128. 

Swan,  black,  wild,  trachea  of  the,  ^4;  white,  young  of,  550;  red 
beak  of  the,  559;  black-necked,  562. 

Swans,  559,  562;  young,  548. 

Swaysland,  Mr.,  on  the  arrival  of  migratory  birds,  240. 

Swifts,  migration  of,  122. 

Swinhoe,  R.,  on  the  common  rat  in  Formosa  and  China,  91; 
behavior  of  lizards  when  caught,  403;  on  the  sounds  produced  by 
the  male  hoopoe,  427;  on  Dicrurus  niacrocercus  and  the  spoonbill, 
524;  on  the  young  of  Ardeola,  534;  on  the  habits  of  Ttirnix,  542;  on 
the  habits  of  BhyiicJuEa  bengalensis,  543;  on  Orioles  breeding  in 
immature  plumage,  552. 

Sylvia  atricapUla,  young  of,  554;  sylvia  cinerea,  aerial  love-dance 
of  the  male,  432. 

Sympathy,  152;  among  animals,  115;  its  supposed  basis,  120. 

Sympathies,  gradual  widening  of,  139. 

Syngnathous  fishes,  abdominal  pouch  in  male,  185. 

Syph£otid€8  auntus,  acuminated  primaries  of  the  male,  429;  ear- 
tufts  of,  436. 

Tabanidae,  habits  of,  235. 

Tadoma  variegata,  sexes  and  young  of,  546;  tadoma  milpan- 
ser,  471. 

Tahitians,  164;  compression  of  the  nose  by  the,  665. 

Tail,  rudimentary,  occurrence  of,  in  man,  25;  convoluted  body  in 
the  extremity  of  tlie,  25;  absence  of,  in  man  and  the  higher  apes,  65; 
variability  of,  in  species  of  Macacris  and  in  baboons,  65;  presence  of, 
in  the  early  progenitors  of  man,  182;  length  of,  in  pheasants,  507, 
513,  514;  difference  of  length  of  the,  in  the  two  sexes  of  birds,  513. 

Tait,  Lawson,  on  the  effects  of  natural  selection  on  civilized 
nations,  151, 


788  INDEX. 

Tanager,  scarlet,  variation  in  tlie  male,  481. 

Tanagra  (estiva,  age  of  mature  plumage  in,  551. 

Tanagra  rubra,  481;  young  of,  555. 

Tanais,  absence  of  mouth  in  the  males  of  some  species  of.  235;  rela 
tions  of  the  sexes  in,  287;  dimorphic  males  of  a  species  of,  300. 

Tankerville,  Earl,  on  the  battles  of  wild  bulls,  571. 

Tanysiptera,  races  of,  determined  from  adult  males,  533;  tanp- 
siptera  sylvia,  long-tailed  feathers  of,  513. 

Taphroderes  distortHH,  enlarged  left  mandible  of  the  male,  313. 

Tapirs,  longitudinal  stripes  of  young,  529,  623. 

Tarsi,  dilatation  of  front,  in  male  beetles,  312. 

Tardus,  178. 

Tasmania,  half-castes  killed  by  the  natives  of,  194. 

Tasmanians,  extinction  of,  209. 

Taste,  in  the  Quadrumana,  618. 

Tattooing,  203;  universality  of,  655. 

Taylor,  G.,  on  Quiscalus  major,  281. 

Taylor,  Rev.  R.,  on  tattooing  in  New  Zealand,  657. 

Tea,  fondness  of  monkeys  for,  7. 

Teal,  constancy  of,  466. 

Tear-sacs,  of  Ruminants,  604. 

Teebay,  Mr.,  on  changes  of  plumage  in  spangled  Hamburg 
fowls,  259. 

Teeth,  rudimentary  incisor,  in  Ruminants,  12;  posterior  molar  in 
man,  22;  wisdom,  22;  diversity  of,  30;  canine,  in  the  early  pro- 
genitors of  man,  182;  canine,  of  male  mammals,  572;  in  man,  re- 
duced by  correlation,  641;  staining  of  the,  655;  front,  knocked  out 
or  filed  by  some  savages,  656. 

Tegetmeier,  Mr. ,  on  the  transmission  of  colors  in  pigeons  by  one 
sex  alone,  262;  numerical  proportion  of  male  and  female  births  in 
dogs,  278;  on  the  abundance  of  male  pigeons,  280;  on  the  wattles  of 
game-cocks,  458;  on  the  courtship  of  fowls,  473;  on  the  loves  of 
pigeons,  474;  on  dyed  pigeons,  474;  blue  dragon  pigeons,  508. 

Tembeta,  S.,  American  ornament,  656. 

Temper,  in  dogs  and  horses,  inherited,  78. 

Tench,  proportion  of  the  sexes  in  the,  282;  brightness  of  male, 
during  breeding  season,  386. 

Tenebrionidae,  stridulation  of,  342. 

Tennent,  Sir  J.  E.,  on  the  tusks  of  the  Ceylon  elephant,  578,  587; 
on  the  frequent  absence  of  beard  in  the  natives  of  Ceylon,  638;  on 
the  Chinese  opinion  of  the  aspect  of  the  Cingalese,  659. 

Tennyson,  A.,  on  the  control  of  thought,  139. 

Tenthredinidae,  proportions  of  the  sexes  in,  286;  fighting  habits  of 
male,  330;  difference  of  the  sexes  in,  331. 

Tephrodornis,  young  of,  533. 

Terai,  in  India,  207. 

Termites,  habits  of,  330. 

Terns,  white,  560;  and  black,  561;  seasonal  change  of  plumage 
in,  560. 

Terror,  common  action  of,  upon  the  lower  animals  and  man,  77. 

Testudo  elegans,  398;  testudo  nigra,  397. 

Tetrao  cupido,  battles  of,  417;  sexual  difference  in  the  vocal 
organs  of,   422;   tetrao  phasianellus,    dances   of,    431;    duration   of 


Index.  789 

dances  of,  460;  teirao  gcoticus,  518,  530,  537;  tetrao  tetrix,  518,  530, 
537;  pugnacity  of  the  male,  412;  tetrao  uinbellus,  pairing  of,  417; 
battles  of,  417;  drumming  of  the  male,  426;  tetrao  urogaZlaides, 
dances  of,  460;  tetrao  urogallus,  pugnacity  of  the  male,  412;  tetrao 
uropha^iatius,  inflation  of  the  oesophagus  in  the  male,  423. 

TJuimiiobia,  young  of,  533. 

Theda,  sexual  differences  of  coloring  in  species  of,  351;  tTieelarubi, 
protective  coloring  of,  353. 

Thecophora  fovea,  349. 

Theognis,  selection  in  mankind,  33. 

Therviion,  stridulation  of  males  of,  309;  theridion  lineatum,  308. 

Thomisus  citreus,  and  T.  floiHcolens,  difference  of  color  in  the  sexes 
of,  307. 

Thompson,  J.  H.,  on  the  battles  of  sperm-whales,  571. 

Thompson,  W.,  on  the  coloring  of  the  male  char  during  the 
breeding-season,  386;  on  the  pugnacity  of  the  males  of  GaUinula 
cJdoropus,  409;  on  the  finding  of  new  mates  by  magpies,  462;  on  the 
finding  of  new  mates  by  Peregrine  falcons,  463. 

Thorax,  processes  of,  in  male  beetles,  334. 

Thorell,  T.,  on  the  proportion  of  the  sexes  in  spiders,  287. 

Thornback,  difference  in  the  teeth  of  the  two  sexes  of  the,  379. 

Thoughts,  control  of,  139. 

Thrush,  pairing  with  a  blackbird,  470;  colors  and  nidification  of 
the.  518. 

Thrushes,  characters  of  young,  518,  529. 

Thug,  remorse  of  a,  133. 

Thumb,  absence  of,  in  Ateles  and  Hylohates,  57. 

Thury,  M. ,  on  the  numerical  proportion  of  male  and  female  births 
among  the  Jews,  275. 

Ihylacinus,  possession  of  the  marsupial  sac  by  the  male,  183. 

Thysanura,  317. 

Tibia,  dilated,  of  the  male  Crabro  cribrarius,  313;  and  femur,  pro- 
portions of,  in  the  Aymara  Indians,  39. 

Tierra  del  Fuego,  marriage-customs  of,  683. 

Tiger,  colors  and  markings  of  the,  622. 

Tigers,  depopulation  of  districts  by,  in  India,  52. 

TiUtLS  elongatus,  difference  of  color  in  the  sexes  of,  333. 

Timidity,  variability  of,  in  the  same  species,  78. 

Tinea  'vulgaris,  282. 

Tipula,  pugnacity  of  male,  317, 

Tits,  sexual  difference  of  color  in,  521. 

Toads,  395;  male,  treatment  of  ova  by  some,  185;  male,  ready  to 
breed  before  the  female,  240. 

Todas,  infanticide  and  proportion  of  sexes,  288;  practice  polyandry, 
677;  choice  of  husbands  among,  677. 

Toe,  great,  condition  of,  in  the  human  embryo,  12. 

Tomicus  villosus,  proportion  of  the  sexes  in,  286. 

Tomtit,  blue,  sexual  difference  of  color  in  the,  521. 

Tonga  Islands,  beardlessness  of  the  natives  of,  639,  663. 

Tooke,  Home,  on  language,  97. 

Tools,  flint,  164;  used  by  monkeys,  91;  use  of,  54. 

Topnots  in  birds,  438. 

Tortoise,  voice  of  the  male,  646. 


790  INDEX. 

Tortures,  submitted  to  by  American  savages,  134. 

Totanus,  double  moult  in,  442. 

Toucans,  colors  and  nidification  of  tlie,  518;  beaks  and  ceres  of 
tbe,  560. 

Towns,  residence  in,  a  cause  of  diminished  stature,  35. 

Toynbee,  J.,  on  tbe  external  sbell  of  tbe  ear  in  man,  15. 

Tracbea,  convoluted  and  imbedded  in  tbe  sternum,  in  some  birds, 
425;  structure  of  tbe,  in  RhynclKBa,  542. 

Trades,  affecting  tbe  form  of  tbe  skull,  62. 

7'ragelaphus,  sexual  differences  of  color  in,  611;  tragelaphus 
scriptus,  dorsal  crest  of,  606;  markings  of,  621. 

Tragopan,  249;  swelling  of  tbe  wattles  of  tbe  male,  during  court- 
sbip,  434;  display  of  plumage  by  tbe  male,  451;  marking  of  tbe 
sexes  of  tbe,  487. 

Tragops  dispar,  sexual  difference  in  tbe  color  of,  399. 

Training,  effect  of,  on  tbe  mental  difference  between  tbe  sexes  of 
man,  645. 

Transfer  of  male  characters  to  female  birds,  536. 

Transmission,  equal,  of  ornamental  characters,  to  botb  sexes  in 
mammals,  618. 

Traps,  avoidance  of,  by  animals,  90;  use  of,  54. 

Treachery,  to  comrades,  avoidance  of,  by  savages,  126. 

Tremex  cohimbce,  331. 

Tribes,  extinct,  145;  extinction  of,  207. 

THchius,  difference  of  color  in  the  sexes  of  a  species  of,  333. 

THgla,  394. 

Trigonocepbalus,  noise  made  by  tail  of,  401, 

Trimen,  R.,  on  tbe  proportion  of  tbe  sexes  in  South  African  but- 
terflies, 283;  on  tbe  attraction  of  males  by  tbe  female  Lasiocampa 
quercus,  284 ;  on  Pneuraora,  326 ;  on  difference  of  color  in  the 
sexes  of  beetles,  333;  on  moths  brilliantly  colored  beneath,  357;  on 
mimicry  in  butterflies,  367,  368;  on  Oynanisa  Ms,  and  on  the  ocel- 
lated  spots  of  Lepidoptera,  486;  on  Cyllo  Leda,  486. 

Tnnga,  sexes  and  young  of,  553;  tringa  cornuta,  AAA. 

Tnphcena,  coloration  of  tbe  species  of,  355. 

Tristram,.  H.  B.,  on  unhealthy  districts  in  North  Africa,  221;  on  the 
habits  of  the  chaffinch  in  Palestine,  281 ;  on  the  birds  of  the  Sahara, 
519;  on  the  animals  inhabiting  tbe  Sahara,  557. 

Triton  cristatas,  394;  triton  palmipes,  394;  tHton  punctatus,  394, 
395. 

Troglodyte  skulls,  greater  than  those  of  modern  Frenchmen,  62. 

Troglodytes  vulgaris,  539. 

Trogons,  colors  and  nidification  of  tbe,  518. 

Tropic- birds,  white  only  when  mature,  560. 

Tropics,  freshwater  fishes  of  tbe,  389. 

Trout,  proportion  of  tbe  sexes  in,  281;  male,  pugnacity  of 
tbe,  377. 

Trox  sahulosus,  stridulation  of,  343. 

Truth,  not  rare  between  members  of  the  same  tribe,  133;  more 
highly  appreciated  by  certain  tribes,  138. 

Tullocb,  Major,  on  tbe  immunity  of  tbe  negro  from  certain 
fevers,  220. 

Tumbler,  almond,  change  of  plumage  in  tbe,  269. 


INDEX.  791 

Tardus  mertUa,  518;  young  of,  554;  turdus  migratoriu^,  529; 
turd^is  musicus,  518;  turdus  polyglottus,  young  of,  554;  turdus  tor- 
quntus,  518. 

Turkey,  wild,  pugnacity  of  young  male,  414;  wild,  notes  of  the, 
425;  swelling  of  the  wattles  of  tlie  male,  434;  variety  of,  with  a  top- 
knot, 488;  recognition  of  a  dog  by  a,  468;  male,  wild,  acceptable  to 
domesticated  females,  475 ;  wild,  first  advances  made  by  older 
females,  477;  wild,  breast-tuft  of  bristles  of  the,  525. 

Turkey-cock,  scraping  of  the  wings  of,  upon  the  ground,  426; 
wild,  display  of  plumage' by,  447;  fighting  habits  of,  458. 

Turner,  Prof.  W.,  on  muscular  fasciculi  in  man  referable  to  the 
panniculus  camosus,  14;  on  the  occurrence  of  the  supra-condyloid 
foramen  in  the  human  humerus,  24;  on  muscles  attached  to  the 
coccyx  in  man,  25;  on  the  JUum  ter.minale  in  man,  25;  on  the  varia- 
bility of  the  muscles,  30;  on  abnormal  conditions  of  the  human 
uterus,  43;  on  the  development  of  the  mammary  glands,  184;  on 
male  fishes  hatching  ova  in  their  mouths,  185,  391 ;  on  the  external 
perpendicular  fissure  of  the  brain,  228;  on  the  bridging  convolutions 
in  the  brain  of  a  chimpanzee,  228. 

Turnix,  sexes  of  some  species  of,  542,  547. 

Turtle-dove,  cooing  of  the,  425. 

Tuttle,  H.,  on  the  number  of  species  of  man,  199. 

Tylor,  E.  B.,  on  emotional  cries,  gestures,  etc.,  of  man,  96;  on  the 
origin  of  the  belief  in  spiritual  agencies,  106;  remorse  for  violation 
of  tribal  usage  in  marrying,  130;  on  the  primitive  barbarism  of 
civilized  nations,  162;  on  the  origin  of  counting,  162;  inventions 
of  savages,  164 ;  on  resemblances,  of  the  mental  characters  in 
different  races  of  man,  203. 

Type  of  structure,  prevalence  of,  186. 

TypTmus,  stridulating  organs  of,  341 ;  stridulation  of,  343. 

Twins,  tendency  to  produce,  hereditary,  51. 

Twite,  proportion  of  the  sexes  in  the,  281. 

Ugliness,  said  to  consist  in  an  approach  to  the  lower  animals,  666, 

Umbrella-bird,  423. 

UmbHna,  sounds  produced  by,  394. 

United  States,  rate  of  increase  in,  50;  influence  of  natural  selec- 
tion on  the  progress  of,  161 ;  change  undergone  by  Europeans  in 
the,  223. 

tlpiipa  epops,  sounds  produced  by  the  male,  427. 

Uraniidae.  coloration  of  the,  356. 

Uii/i  troile,  variety  of  (=  U.  lacrymans),  482. 

Urodela,  394. 

Urosticte  Benjamini,  sexual  differences  in,  502. 

Use  and  disuse  of  parts,  effects  of,  36;  influence  of,  on  the  races 
of  man,  224. 

Uterus,  reversion  in  the,  43;  more  or  less  divided,  in  the  human 
subject,  43,  48;  double,  in  the  early  progenitors  of  man,  183. 

Vaccination,  influence  of,  151. 

Vancouver  Island,  Mr.  Sproat  on  the  savages  of,  208;  natives  of, 
eradication  of  facial  hair  by  the,  662. 

VaiieUus  cristatus,  wing  tubercles  of  the  male,  414. 

Vnnessm,  350 ;  resemblance  of  lower  surface  of,  to  bark  of 
trees,  353. 


•^92  INDEX. 

Variability,  causes  of,  31;  in  man,  analogous  to  that  in  the  lower 
animals,  33;  of  the  races  of  man,  198  ;  greater  in  men  than  in 
women,  252;  period  of,  relation  of  the,  to  sexual  selection,  272;  of 
birds,  479;  of  secondary  sexual  characters  in  man,  638. 

Variation,  laws  of,  33;  correlated,  48;  in  man,  166;  analogous,  173; 
analogous,  in  plumage  of  birds,  438. 

Variations,  spontaneous,  49. 

Varieties,  absence  of,  between  two  species,  evidence  of  their  dis- 
tinctness, 189. 

Variety,  an  object  in  nature,  561. 

Variola,  communicable  between  man  and  the  lower  animals,  7. 

Vaureal,  human  bones  from,  24. 

Veddahs,  monogamous  habits  of,  675. 

Veitch,  Mr.,  on  the  aversion  of  Japanese  ladies  to  whiskers,  663. 

Vengeance,  instinct  of,  127. 

Venus  Erycina,  priestesses  of,  670. 

Vermes,  299. 

Vermiform  appendage,  23. 

Verreaux,  M. ,  on  the  attraction  of  numerous  males  by  the  female 
of  an  Australian  Bonibyx,  284. 

Vertebrae,  caudal,  number  of,  in  macaques  and  baboons,  65;  of 
monkeys,  partly  imbedded  in  the  body,  66. 

Vertebrata,  375;  common  origin  of  the,  180;  most  ancient  progeni- 
tors of,  183;  origin  of  the  voice  in  air  breathing,  646. 

Vesicula  prostatica,  the  homologue  of  the  uterus,  26,  183. 

VibrisssB,  represented  by  long  hairs  in  the  eyebrows,  20. 

Vidua,  457,  526;  vidua  axillaris,  248. 

Villerme,  M.,  on  the  influence  of  plenty  upon  stature,  35. 

Vinson,  Aug.,  courtship  of  male  spider,  308  ;  on  the  male  of 
Epeira  7iigra,  309. 

Viper,  difference  of  the  sexes  in  the,  398. 

Virey,  on  the  number  of  species  of  man,  199. 

Virtues,  originally  social  only,  132;  gradual  appreciation  of,  148. 
Viscera,  variability  of,  in  man,  30. 

Vlacovich,  Prof.,  on  the  ischio-pubic  muscle,  46. 

Vocal  music  of  birds,  417;  vocal  organs  of  man,  98;  of  birds,  96, 
512;  of  frogs,  397;  of  the  Insessores,  421;  difference  of,  in  the  sexes 
of  birds,  421;  primarily  used  in  relation  to  the  propagation  of  the 
species,  646. 

Vogt,  Karl,  on  the  origin  of  species,  1;  on  the  origin  of  man,  3; 
on  the  semilunar  fold  in  man,  19;  on  microcephalous  idiots,  40;  on 
the  imitative  faculties  of  microcephalous  idiots,  98;  on  skulls  from 
Bra/ilian  caves,  192,  on  the  evolution  of  the  races  of  man,  201;  on 
the  formation  of  the  skull  in  women,  635;  on  the  Ainos  and  negroes, 
639;  on  the  increased  cranial  difference  of  the  sexes  in  man  with 
race  development,  645;  on  the  obliquity  of  the  eye  in  the  Chinese 
and  Jai)anese,  659. 

Voice  in  mammals,  600;  in  monkeys  and  man,  636;  in  man,  645; 
origin  of,  in  air-breathing  vertebrates,  646. 

Von  Baer,  see  Baer. 

V^ulpian,  Prof.,  on  the  resemblance  between  the  brains  of  man  and 
the  higher  apes,  6. 

Vultures,  selection  of  a  mate  by  the  female,  473;  colors  of,  561. 


INDEX.  793 

Waders,  young  of,  553. 

Wagner,  *R.,  on  the  occurrence  of  the  diastema  in  a  Kaflir  skull, 
45;  on  the  bronchi  of  the  black  stork,  425. 

Wagtail,  Kay's,  arrival  of  the  male  before  the  female,  240. 

Wagtails,  Indian,  young  of,  534. 

Waist,  proportions  of,  in  soldiers  and  sailors,  37. 

Waitz,  Prof.,  on  the  number  of  species  of  man,  199;  on  the  liabil- 
ity of  negroes  to  tropical  fevers  after  residence  in  a  cold  climate,  221 ; 
on  the  color  of  Australian  infants,  636;  on  the  beardlessness  of 
negroes,  639;  on  the  fondness  of  mankind  for  ornaments,  654;  on 
negro  ideas  of  female  beauty,  660;  on  Javan  and  Cochin  Chineses 
ideas  of  beauty,  661. 

Waldever,  M.,  on  the  hermaphroditism  of  the  vertebrate  em- 
bryo, 183'. 

Wales,  North,  numerical  proportions  of  male  and  female  births 
in,  274. 

VValkenaer  and  Gervais,  spider  attracted  by  music,  309;  on  the 
Myriapoda,  310. 

Walker,  Alex. ,  on  the  large  size  of  the  hands  of  laborers'  chil- 
dren, 37. 

Walker,  F.,  on  sexual  differences  in  the  diptera,  317. 

Wallace,  Dr.  A, ,  on  the  prehensile  use  of  the  tarsi  in  male  moths, 
237;  on  the  rearing  of  the  A'ilanthus  silkmoth,  284;  on  breeding 
Lepidoptera,  284:  proportion  of  sexes  of  Bairibyr  cyrdhia,  B.  yama- 
mai,  and  B.  Pernyi  reared  by,  285;  on  the  development  of  Bambyx 
cyiithia  and  B.  yamamai,  315;  on  the  pairing  of  Bombyx  cyntJda,  360. 

Wallace,  A.  K.,  on  the  origin  of  man,  3;  on  the  power  of  imita- 
tion in  man,  77;  on  the  use  of  missiles  by  the  orang,  92;  on  the 
vary  appreciation  of  truth  among  different  tribes,  138;  on  the  limits 
of  natural  selection  in  man,  144;  on  the  occurrence  of  remorse  among 
savages,  149;  on  the  effects  of  natural  selection  on  civilized  nations, 
151;  on  the  use  of  the  convergence  of  the  hair  at  the  elbow  in  the 
orang,  172;  on  the  contrast  in  the  characters  of  the  Malays  and 
Papuans,  191 ;  on  the  line  of  separation  between  the  Papuans  and 
Malays,  192;  on  the  birds  of  paradise,  248;  on  the  sexes  of  Omi- 
thoptera  Vrcesiis,  283;  on  protective  resemblances,  295;  on  the  rela- 
tive sizes  of  the  sexes  of  insects,  315;  on  Klaphomyia,  317;  on  the 
pugnacity  of  the  males  of  LeptorJiynchus  angustatus,  339;  on  sounds 
produced*  by  Kuchirus  lonyimanus,  344;  on  the  colors  of  Diadenw., 
350;  on  Kallima,  353;  on  the  protective  coloring  of  moths,  355;  on 
bright  coloration  as  protective  in  butterflies,  356;  on  variability  in 
the  Papilionidae,  363;  on  male  and  female  butterflies  inhabiting  dif- 
ferent stations,  364;  on  the  protective  nature  of  the  dull  coloring  of 
female  butterflies,  364,  365,  367;  on  mimicry  in  butterflies,  367;  on 
the  bright  colors  of  caterpillars,  369;  on  brightly  colored  fishes  fre- 
quenting reefs,  389;  on  the  coral  snakes,  400;  on  Paradisea  apoda, 
438;  on  the  display  of  plumage  by  male  birds  of  paradise,  449;  on 
assemblies  of  birds  of  paradise,  460;  on  the  instability  of  the  ocel- 
lated  spots  in  Hipparchia  Janira,  486;  on  sexually  limited  inherit- 
ance, 505;  on  the  sexual  coloration  of  birds,  514,  538,  539,  541.  546; 
on  the  relation  between  the  colors  and  nidification  of  birds,  515,  518; 
on  the  coloration  of  the  Cotingidae,  523;  on  the  females  of  Paradisea 
apoda  and  papuana,  535;  on  the  incubation  of  the  cassowary,  545; 


794  LSTDSX. 

«»  inolectiTe  coloratiim  in  birds,  556;  on  the  Babimsa,  592;  on  the 
markings  of  the  tiger,  GS3;  <hi  the  beards  of  the  Papaans,  639;  on 
the  hair  of  the  Papoans,  656;  <mi  the  distribntion  of  hair  on  the 
hnman  body,  685. 

Walms,  dereloiMnent  of  the  nictitating  membrane  in  the,  19; 
tnsks  of  the,  573,  578;  nse  of  the  tasks  bj  the,  585. 

Walsh,  R  D.,  cm  the  proportion  of  the  sexes  in  PapUio  Tumus, 
283;  on  the  Cpiij^dae  and  Ceadranjidje,  286;  <mi  the  jaws  of  Am^ 
fliopiUZa,  312;  <hi  Corydalis  eornutu*^  312;  <m  the  prehensile  organs 
of  male  insects,  312;  <m  the  antennae  of  Ptnthe,  313;  aa.  the  caudal 
appendages  of  dragim  flies.  313;  <m  PlatjfphjfBum  caneatfum,  324;  (m 
the  sexes  of  the  Ephemeridae,  328;  on  the  difference  of  color  in  the 
sexes  of  S^peUnm  fmaratum,  328;  on  sexes  of  dragon  flies.  328;  on 
the  difference  of  the  sexes  in  the  Ichneomonidae,  331;  <m  the  sexes 
of  Onodaena  atra,  333;  aa  the  vaiiaticm  of  the  horns  of  the  male 
PtunuBO*  carmfaty  336;  on  the  coloratifm  of  the  species  of  Aniho- 
ekaris,  354. 

WiqMti,  battles  of,  571 ;  traces  of  horns  in  the  female,  574;  attack- 
ing a  man,  582;  crest  of  the  male,  606;  sexual  difference  in  ihe  color 
of  the,  612. 

Waibler.  hedge,  539;  joung  of  the.  548. 

Wazfol^s,  superb,  nidiilcation  of,  517. 

Wariness,  acquired  bj  animals,  91. 

Warington.  B.,  on  the  habitus  of  the  sti<^ehadc,  376,  391;  on  the 
hrilliant    col<»s   of   the   male    stickleback   during    the    breeding- 


Wart^hcg.  tusks  and  pads  of  the,  593u 

Watdimakeis,  short-sighted,  37. 

Wat^-hen,  409. 

Waterhouse,  C.  O.,  on  blind  beetles,  333;  cm  difference  of  color  in 
the  sexes  of  beetles.  333. 

Wateihonse,  6.  B.,  on  the  rmce  of  HyUbate*  agOU,  647. 

Water-ouzel,  518;  autumn  smig  of  the,  ASSd. 

^'atertmi,  C,  <hi  the  Bell-lnrd,  441;  <m  the  pairing  of  a  Canada 
goose  with  a  Bemicle  gander,  471;  cm  hares  fighting,  570. 

Wattles,  disadrantageous  to  male  tnrds  in  fighting,  458. 

Weale,  J.  Hansel,  on  a  South  African  caterpillar,  369. 

Wealth,  influence  of,  152. 

Weapms,  used  bj  man,  54;  employed  bj  mcmkeTS.  91;  offensiTe, 
of  males,  238;  of  mammals,  571;  et  seq. 

WeaTer-bird,  420. 

Weaver-lnrds.  rattling  of  the  wings  of,  426;  assemblies  of,  460. 

Webb,  I>r.,  on  the  wisdom  teeth,  22. 

Wedderbum,  Mr.,  assranblj  of  black  game,  462. 

Wedgwood,  Hoislragh,  on  the  orig^  of  language,  98. 

Weevils,  scacual  difference  in  length  of  snout  in  stHue,  235. 

War.  Harmon,  <m  the  numerical  proportion  of  the  sexes  in  pigs 
and  rablnts,  279;  on  the  sexes  of  joang  pigeons,  280;  on  the  songs  of 
birds,  418;  on  {ngems.  467;  on  the  dislike  of  blue  pigeons  to  odier 
coloreA  Tari^ties,  474;  on  the  desertion  of  their  mates  bj  female 
pigeons,  475. 

Weir,  J.  Jenner,  <m  the  nightingale  and  blackcap,  240;  on  the 
idatiTe   sexual    maturity  of  male  birds,  241;  on  fCTiale  pigeons 


ja  feeble  mafte.  SIS;  on  tluee  sttariings 
nest,  S48;  cm  the  pn^M>rti««  of  the  sexes  in  Maehelm  i 
other  birds,  280;  on  the  coloration  of  the  Tripkmmm^  3S5;  on  the 
rejection  of  certain  catsfHllars  bj  birds,  360;  <m  sexual  difeenees  ai. 
the  beak  in  the  giddfineh,  408;  on  a^ping:ba]]findi,  418;  ontfaeobject 


of  the  n^htingale's  simg,  418;  «n  song:  birds,  419;  on  idie  pognadttj 
of  nudefine-i^aniaged bMs,  4M;  on  the  coorttship of  Iwrds,  435;  on 
the  fiiKJingr  of  new  males  by  Peiegrine-fcJcons  and  Kestrels,  4Bi;  on 
the  bollfindli  and  starling,  464;  cm  the  cause  of  Inrds  remainiag  un- 
paired, 465;  on  starling  and  parrots  living  in  triplets,  466;  on  ree^- 
nition  of  color  bj  birds,  468;  on  hjl»id  birds,  410;  on  the  selectian 
of  a  greenfinch  by  a  female  canarjr,  4T3;  on  a  case  <rf  rnralrj  of 
female  bnllfiiidies,  477;  on  the  maturity  of  the  gKdden-pheasantv  551. 

W^sbadi,  I>r.,  measurement  of  men  of  different  raees^  191;  on  the 
greater  Tariability^  of  men  than  «rf  women,  25S;  on  the  relative  pvo- 
piHtians  of  the  body  in  the  sexes  of  different  races  <rf  man,  638. 

Weismaiin,  Prof.,  cakMs  of  Lgeamm,  354. 

Welcker,  M.,  en  bnchycephaly  and  dolidiocephaly,  63;  on  sexual 
differraices  in  the  skull  in  man,  6^. 

Wells,    Dr.,    on   the    immunity   of   coloted 


Westring,  on  the  siridulation  of  males  <rf  Tk/enOiom^  300;  on  the 
stridulatiim  of  Bednttms  perxmatm*^  319;  on  the  stiidulation  of  bee- 
tlBEi,  313;  on  the  stiidulation  ai  OautUtpGa  hrmmmm^  344;  on  the 
atridulating  oigans  of  the  Cbleoplesa,  3^:  on  sounds  ^odueed  by 

Westrappv  H.  M.,  on  reason  in  a  bear,  86;  cm  tdie  prevalenee  <rf 
certain  forms  of  ornamentation,  S03u 

Westwood,  J.  O..  on  the  clawafication  off  theHymenoptera,  1C8;  on 
the  Culiddje  and  Tabanidje,  235;  on  a  Hymenopterons  pan^te  widi 
a  sedentary  mal^  251;  cm  the  {HopiHiions  of  the  sexes  in  Lmemmu 
eermu  and  Skifftmimm,  286;  on  the  afaarace  of  ocelli  in  female  M nt- 


midae,  311;  on  the  jaws  of  AmmapkSa^  31S;  on  lOie  ci^nlation  <rf 
312;  on  the  male  of  C?^aftfv  ( 


of  distinct  species^  312;  on  the  male  of  C?^aftfv  erihrariH^  31S; 
on  the  pngnacH^  of  male  l^ndm,  317;  on  the  stridulation  of  Pirmtem 
atridwtu*,  319;  on  the  Cicadae,  319;  on  the  stridulating  otgansof  the 
cricket,  322;  on  Epkippi^er  wUimm,  323;  cm  I^Mwmmra^  335;  on  the 
pugnacity  of  the  Mantid^  327;  cm  PiatgUemmmM,,  327;  on  diffieienee 
in  the  sexes  of  the  Agricmidae,  328;  on  the  pugnacity  off  the  males  ^ 
a  species  of  Tenthredinae,  330;  on  the  pugnacity  of  the  male  slag- 
be^e,  339;  on  BledivM  tamrmM  and  Baffmmmm,  338;  on  lamellieam 
beetles,  341;  on  the  odcnation  of  LUkoaia,  356. 

Whale,  Spenn,  battles  off  male,  570,  58& 

Whales,  nakedness  of,  63. 

Whateley,  Arch.,  language  not  peculiar  to  man,  95;  cm  the  psimi- 
tiTO  ciTilixaticm  of  man,  162. 

Whewell,  Prof.,  on  maternal  affection,  "78. 

Whiskers,  in  monkeys,  171. 

White,  F.  &,  noise  produced  by  BgUifkaM,  349. 

White,  QUbert,  cm  tiMB  proporlicm  of  the  sexes  in  the  partridge,  280; 
cm  the  house-cricket,  321;  cm  the  object  of  the  song  of  lurds^  419;  cm 
the  finding  of  new  mates  by  white  owls,  463;  on  spring  eonTcys  of 
male  partndgea.,  463i,  464. 


796  INDEX. 

Wliiteness,  a  sexual  ornament  in  some  birds,  563;  of  mammals  in- 
habiting snowy  countries,  619. 

VVhite-tbroat,  aerial  love-dance  of  the  male,  432. 

Whitney,  Prof.,  on  the  development  of  language,  97;  language 
not  indispensable  for  thought,  100. 

Widgeon,  pairing  with  a  pintail  duck,  471. 

Widow-bird,  polygamous,  248;  breeding  plumage  of  the  male,  445, 
457;  female,  rejecting  the  unadorned  male,  476. 

Widows  and  widowers,  mortality  of,  158. 

Wilckens,  Dr.,  on  the  modification  of  domestic  animals  in  mount- 
ainous regions,  40;  on  a  numerical  relation  between  the  hairs  and 
excretory  pores  in  sheep,  225. 

Wilder,  Dr.  Burt,  on  the  greater  freqaeney  of  supernnmerary 
digits  in  men  than  in  women,  253. 

Williams,  on  the  marriage-customs  of  the  Fijians,  684. 

Wilson,  Dr.,  on  the  conical  heads  of  the  natives  of  Northwestern 
Africa,  665;  on  the  Fijians,  665;  on  the  persistence  of  the  fashion  of 
compressing  the  skull,  666. 

Wing-spurs,  413,  511. 

Wings,  differences  of,  in  the  two  sexes  of  butterflies  and  Hymen- 
optera,  314;  play  of,  in  the  courtship  of  birds,  455. 

Winter,  change  of  color  of  mammals  in,  619. 

Witchcraft,  108. 

Wives,  traces  of  the  forcible  capture  of,  163. 

Wolf,  winter  change  of  the,  619. 

Wolff,  on  the  variability  of  the  viscera  in  man,  30. 

WoUaston,  T.  V.,  on  Eurygnathus,  314;  on  musical  Curculionidse^ 
341;  on  the  stridulation  of  Acalles,  346. 

Wolves  learning  to  bark  from  dogs,  82;  hunting  in  packs,  114; 
black,  616. 

Wombat,  black  varieties  of  the,  616. 

Women  distinguished  from  men  by  male  monkeys,  9;  preponder- 
ance of,  in  numbers,  276;  selection  of,  for  beauty,  682;  effects  of 
selection  of,  in  accordance  with  different  standards  of  beauty,  666; 
practice  of  capturing  673,  676;  early  bethrothals  and  slavery  of,  677; 
freedom  of  selection  by,  in  savage  tribes,  683. 

Wonder,  manifestations  of,  by  animals,  80. 

Wonfor,  Mr.,  on  sexual  peculiarities  in  the  wings  of  butterflies,  314; 
Wood,  J.,  on  muscular  variations  in  man,  29,  46,  47;  on  the  greater 
variability  of  the  muscles  in  men  than  in  women,  253;  Wood,  T.  W., 
on  the  coloring  of  the  orange-tip  butterfly,  355;  on  the  habits  of  the 
Saturniidae,  358;  quarrels  of  chamseleons,  405 ;  on  the  habits  of 
Menura  Alberti,  421  ;  on  Tetrao  ciqndo,  422 ;  on  the  display  of 
plumage  by  male  pheasants,  449,  451;  on  the  ocellated  spots  of  the 
Argus  pheasant,  501;  on  fighting  of  Menura  superba,  461;  on  the 
habits  of  the  female  cassowary,  545. 

Woodcock,  coloration  of  the,  559. 

Woodpecker,  selection  of  a  mate  by  the  female,  472. 

Woodpeckers,  421;  tapping  of,  426;  colors  and  nidification  of  the, 
518,  521,  529;  characters  of  young,  540,  548,  557. 

Woolner,  Mr.,  observations  on  the  ear  in  man,  16. 

Wormald,  Mr.,  on  the  coloration  of  Hy2)oj)yra,  357. 

Wounds,  healing  of,  8. 


INDEX,  797 

Wren, 539;  young  of  the,  539,  548. 

Wright,  C  A.,  on  the  young  of  Orocetes  and  Petrocincla,  554; 
Wright,  Chauncey,  great  brain-power  requisite  for  language  54;  on 
correlative  acquisition,  651  ;  on  the  enlargement  of  the  brain  in 
man,  697;  Wright,  Mr.,  on  the  Scotch  deerhound,  689;  on  sexual 
preference  in  dogs,  597;  on  the  rejection  of  a  horse  by  a  mare,  598; 
Wright,  W.,  von,  on  the  protective  plumage  of  the  Ptarmigan,  443, 

Writing,  163. 

Wyman,  Prof.,  on  the  prolongation  of  the  coccyx  in  the  human 
embryo,  10;  on  the  condition  of  the  great  toe  in  the  human 
embryo,  12;  on  the  occurrence  of  the  supra-con dyloid  foramen  in  the 
humerus  of  man,  24;  on  variation  in  the  skulls  of  the  natives  of  the 
Sandwich  Islands,  29;  on  the  hatching  of  the  eggs  in  the  mouths 
and  branchial  cavities  of  male  fishes,  185,  391. 

Xenarchus,  on  the  Cicadae,  319. 

Xenophon,  selection  in  mankind  advocated  by,  32. 

Xenorhyiichus,  sexual  difference  in  the  color  of  the  eyes  in,  483. 

Xiphophorus  Helleni,  peculiar  analfin  of  the  male,  382. 

Xylucopn,  difference  of  the  sexes  in,  331. 

Yarrell,  W.,  on  the  habits  of  the  Oyprinidae,  282;  on  Raia  clavata, 
375;  on  the  characters  of  the  male  salmon  during  the  breeding- 
season,  377,  386;  on  the  characters  of  the  rays,  380;  on  the  gemmeous 
dragonet,  381;  on  colors  of  the  salmon,  386;  on  the  spawning  of  the 
salmon,  390;  on  the  incubation  of  the  Lophobranchii,  392;  on  rivalry 
in  song-birds,  419;  on  the  trachea  of  the  swan,  425;  on  the  moulting 
of  the  Anatidae,  446;  on  the  young  of  the  waders,  553. 

Yellow  fever,  immunity  of  negroes  and  mulattoes  from,  220. 

Youatt,  Mr.,  on  the  development  of  the  horns  in  cattle,  266. 

Yura-caras,  their  notions  of  beauty,  661. 

Zebra,  rejection  of  an  ass  by  a  female,  617;  stripes  of  the,  623. 

Zebus,  humps  of,  608. 

Zigzags,  prevalence  of,  as  ornaments,  204. 

Zincke,  Mr.,  on  European  emigration  to  America,  161. 

Zovtoca  viviparn,  sexual  difference  in  the  color  of,  405. 

Zouteveen,  Dr.,  polydactylism,  42;  proportion  of  sexes  at  Cape  of 
Good  Hope,  275;  spiders  attracted  by  music,  309;  on  sounds  pro- 
duced by  fish,  394. 

Zygaenidae,  coloration  of  the,  356. 

THE  "BtSD, 


fm   84/0i        mnCoiil 


